Salvia splendens

PEST

   NAME

     Capsid bugs

     Lygocoris species

   ORDER

     Hemiptera

   FAMILY

     Miridae

Description of the Pest

Capsid bugs have piercing and sucking mouthparts. They have two pairs of wings, with the forewings thicker at the base and covering the hindwings at rest.

Adult bugs are up to 6 - 12 mm long the wings are coloured two thirds from the body becoming transparent at the end when flatly folded the transparent areas form an obvious diamond-shape. While feeding they secrete a toxic fluid that kills the surrounding cells. They look like large Aphids

Adult      Adult with piercing and sucking mouth parts

Life Cycle

These insects have a Hemimetabolous life cycle i.e. the nymphs resemble the adults.

Distribution of the Pest

Europe and the USA

Life Cycle

These insects have a Hemimetabolous life cycle, i.e. When the nymphs resemble the adults.

Period of Activity

The bugs are most active from late spring to late summer.

Damage Caused

After being attacked the young leaves towards the shoot tips expand and small holes with brown margins are formed. Flowers that are affected may fail to open or open unevenly with damaged petals.

The apple capsid bug (Plesiocoris rugicollis) attacks developing fruit forming blemishes on the skin but not affect the quality of the fruit.

Susceptible Plants

There are many ornamental plants that are attacked; these include Fuchsia, Chrysanthemum, Dahlia, Magnolia, Rosa, Hydrangea and Salvia species. Fruit and vegetables are also susceptible to attack.

Cultural Control

Difficult to control, infected buds may be removed during early spring.

Chemical Control

Infected buds may be sprayed in early spring

Note

It is your responsibility by law to read & follow the directions on the label of any pesticide.

Amendments by B. Sonsie Dip Hort Sc Burnley

PEST

   NAME

     Slugs and Snails

     Various Snails Species

Description of the Pest

Slugs and snails are land molluscs. Snails produce an external spiral shell; slugs do not. The common garden snail Helix asperasa, grows up to 25 mm, long. Its body is slimy, broad, elongated and greyish, with two pairs of reticulated tentacles, with eyes at the ends of the longer pair. The mouth parts of snails and slugs contain a file-like organ known as the radula, which is used to rasp away at the host plant's tissue. Movement of the animal is by a muscular sliding movement, along a slippery trail of mucous; this solidifies on exposure to the air (typically described as a "silvery trail").

                 

Appearance and Distribution of the Pest

Slugs and snails occur world-wide. Slugs tend to be more prevalent in heavier soil types.

Life Cycle

These insects have a Hemimetabolous life cycle, ie. When the immature nymphs resemble the adults.

Snail eggs are laid in moist soil, 20-40mm deep; eggs are white, spherical and appear in clusters of 30-100. Under favourable conditions, eggs hatch in 2-3 weeks. Newly emerged snails resemble tiny adults. When the weather is cold and dry, snails seal themselves into their shells where they survive, dormant, for 1-3 years.

Period of Activity

More active during the warmer months, although some species may remain active throughout the year.

Damage Caused

Native Australian slugs and snails are not commercial pests. Introduced species chew holes in foliage or skeletonise leaves; some plants may be completely defoliated plants; tubers and seedlings may be completely eaten. Slugs and snails feed mainly at night, especially after rain or watering; they shelter in cool, moist locations during the day. When the weather is dry, snails seal themselves into their shells with a mucous membrane, where they survive, dormant, for 1-3 years. Some species may consume up to one third of their body weight each day.

                 

Susceptible Plants

A wide range of leafy plants, including ground crops, potatoes, tubers, leafy vegetables and seedlings.

Fern species are attacked causing serious damage. New fronds are repetitively eaten causing the plant to become stunted. Attacks are normally more severe during wet periods during which time control measures should be taken.

Morinda citrifolia is attacked by the Giant African Snail (Achatina fulica) which defoliates trees.

                 

Cultural Control

Remove possible hiding places and avoid overhead watering to reduce humidity. Cultivate soil regularly; in commercial situations, allow the soil to remain fallow for one season to reduce numbers. Domestic infestations may be removed by hand. Traps may be created by inverting small pots near where snails and slugs are feeding; they will gather in these shelters during the day, and may be collected and destroyed. The popular Australian "beer trap" consists of a vertically-sided container, sunk into the ground and filled with beer, which intoxicates and drowns the snails.

Biological Control

Natural predators such as birds, frogs, and lizards reduce numbers, but do not provide effective control. Orchardists have used running ducks to control snails with some success.

Chemical Control

Commercial baits - molluscicides - made from methiocarb or metaldehyde are effective when used in combination with sanitation. Their effectiveness varies according to soil and weather conditions; it is generally recommended to avoid watering after application.

Note

Always read the label for registration details and direction of use prior to application of any chemicals.

PEST

   NAME

     Caterpillars (General)

     Various species

Description of the Pest

There are many types of caterpillars from moths or butterflies, cutworms, bag moths, case moths, leaf rollers leaf skeletonises. The larvae generally eat leaves, seeds, flowers or buds by chewing out pieces. The size of the piece will depend on the size of the caterpillar and generally they are voracious eaters. The method of eating varies such as the leaf skeletoniser which leaves a network of veins or whole leaves are consumed.

The larvae have mainly 4 or 5 pairs of prolegs except Loopers which have 2 -3 pairs of prolegs. The number of prolegs can help in identifying the insect.

Small and Large Types     

Casuarina Moth (Pernattia exposita) is gregarious, brown with a large head and tufts of hairs that line the slender body. It grows to 25 mm long and forms a tightly woven cocoon on the side of branchlets. The large female adult moth has a stocky body and generally slow moving, the male is smaller.

The larvae cause extensive damage to A. littoralis, A. stricta, C. cunninghamiana, C. glauca, and C. equisetifolia.

The hairy larva feed on the 'leaves" phyllodes, and stems, this can lead to ringbarking and death of branches.

Monitoring

Place sheets on the ground and disturb (shake) the tree for the larva drop to the ground on silken threads.

Spruce Budworm (Choristoneura fumiferana) is a reddish brown with a yellow stripe on its side and chews on the opening buds and the needles of the host. The adult moth is dull grey with brown bands and spots on the wings, appearing in early summer.  The larva is very destructive in northern hemisphere coniferous forests.

Banksia Moth (Danima banksiae) is a caterpillar up to 60 mm long and is brown with black and white markings on its sides and when disturbed it arch backwards and reveal an extruded red underside, close to its head. The grey adult moth has an orange coloured body with a wing span that is up to 80mm across with black and white markings.

Banana moth (Opogona sacchari) is in the order Lepidoptera. This nocturnal moth as a wing span up to 25 mm wide and is bright yellowish brown with a dark brown spot on the wings.  It has a life cycle that lasts approximately 3 months with the eggs hatching in 12 days and the whitish larva with a reddish brown head is up to, 26 mm long, and lives for 50 days at 15° C. In warmer climates life cycle is quicker with up to eight generations per season. The female moth uses a ovipositor to lay up to 500 eggs in groups of five amongst the crevices of the plant. The voracious larvae tunnel into the plant, avoiding light.  In bananas it infests developing fruit and in ornamental plants it prefers the fleshy stems, particularly in cacti, begonias, African violets and is also a serious pest of Pritchardia and Chamaedorea species. Symptoms include tunnelling activity, which may be difficult to see then dead areas appear on the stems. As the caterpillars destroyed xylem tubes leaves begin to wilt and the plant may collapse and die. In European countries it is a glasshouse pest that is controlled chemically.

Pritchardi species      Banana moth larvae

European Pine Shoot Moth (Rhyacionia buoliana) lays eggs on Pinus species during late spring on the new buds and the emerging caterpillars in late summer feed on the shoots causing them to fold and become deformed, eventually dieing.  A major problem in the pine forests of the northern hemisphere

Large Grass Yellow Butterfly (Eurema hecabe) is a small attractive yellow butterfly. with a wing span of 40 mm that lays its eggs on the feathery leaves on Acacia species such as A. baileyana, (Cootamundra wattle), A. spectabilis (glory wattle). Other plant foods include Cassia spp, Caesalpinia spp, Senna spp. Albizia julibrissin (silk tree) A. paraserianthes (Albizia) sp Aeschynomene sp (Budda pea), Indigofera australis (Australian indigo's), Sesbania cannabina (yellow pea-bush), Senna surattensis (Glossy shower), Leucaena leucocephala (wild tamarind).

The small lava are up to 15mm long, green with white lateral bands and feed on the leaves at night in small groups, hiding under the leaves during the day. Large infestations may strip trees and require control. The larva of this insect does not feed on grasses. The adults are important pollinators of many Australian native plants. Various sub species of this insect are found through out Asia.

Gypsy Moth (Porthetria dispar) lava is a hairy grey caterpillar that is marked with blue and red dots along its back and can grow to 75mm long. It is capable of defoliating large trees and is a major problem for several species. A major problem in the northern hemisphere.

Lawn Armyworm

Lawn Armyworm (Spodoptera mauritia) is a plump, smooth caterpillar that is darkish brown to black with multiple stripes and pattens along its body. It can grow to 50mm long and tapers from the head. They are gregarious and move around in groups, like an army. If disturbed the larva drop to the ground and curl up, "faking death"  The larva pupate in the soil. They are a pest of grasses and monocotyledon crops mainly.

This insect is also found throughout Asia.

Monitoring

Drench a known area with old fashion soap 2L / 1000 cm 2. Note the numbers of larvae emerging.

Oblique-banded Leaf Roller (Choristoneura roseceana) lava feeds on the leaves and forms a nest by drawing the leaf margins together using silk threads. The adult moth is up to 25mm across the wingspan and is reddish brown with three darker brown bands across the wings. This is a problem in the apple growing areas of North America. It feeds on Maples, hawthorns, crab apples, Blackberry (bramble) and raspberries.

Red Humped Caterpillar (Schizura concinna) is a lava has a red head and humps with yellow and black strips on the body. It grows from eggs that were laid on the underside of leaves by the adult greyish brown moth that has a wing span up to 30mm across.

Tailed Emperor Caterpillar (Polyura pyrrhus spp. sempronius) adult is a large butterfly with a wing span up to 110 mm with four long tapering tails and the rear of the wings. The fleshy caterpillar with four obvious backward facing horns on a shield shape head. It is dark green with yellowish bands and transversal stripes over its back and grows up to 80 mm in length.

It is commonly found solitary or in small groups. Found over much on mainland Australia. The adults are attracted to overripe fruits they become drunk on this and so are easy to capture. The larvae feed on many plants including, Acacia baileyana (Cootamundra Wattle, A. spectabilis (Glory wattle), Delonix regia (Poinciana), Cinnamomum camphora (Camphor laurel) Robinia pseudoacacia (Black or false locust) Lagerstroemia indica (Crepe Myrtle), Argyrodendron actinophyllum (Black booyong), Celtis spp (Hackberry), Brachychiton spp (Kurrajongs) Gleditsia triacanthos (Honey locust).

Verbena Moth (Crambodes talidiformis) lays its eggs on the outside of the plant and the small green caterpillar that attacks seed pods by entering and eating the contents. It half emerges while pupating appearing as a small brown bump circled by a black ring. Native to North America

White Tussock Moth (Hemerocampa leucostigma) produces lava that is up to 50mm long. It has a red head with a yellow body that is marked in black and has four tufts of hair. The caterpillars pupate on the branches and the eggs laid by the adult moth overwinter on the trunk and are covered in a white waxy material. They are found on Aesculus species. A pest in North America of Oaks.

Life Cycle

This insect has a Holometabolous life cycle, i.e. it has a larval and a pupal stage.

Distribution of the Pest

Many species are found throughout the world from tropical to temperate regions and most of the adults are capable of by flying

Many hairy caterpillars can be irritating      Leaf Skeletonised

Period of Activity

Most active during the warmer months from spring to autumn.

.

Damage Caused

Leaf Rollers

Caterpillar Inside a Tomato

Susceptible Plants

A wide range of native and exotic plants are attacked and can be a major problem in commercial crops or turf grasses. Plants with soft-textured foliage (eg vegetables, some indoor plants) are preferred, but trees and shrubs are commonly attacked.

Malvaceae Abutilon spp, Hibiscus spp and other members of the family are attacked by the castor oil looper, Croton caterpillar (Achaea janata) which feed on leaves. The tip borer Cotton tipworm (Crocidosema plebejana), Rough bollworm (Earias huegeliana) which feeds on young stems, flowers and seeds. A leaf miner (Phyllonorycter spp)

Acer saccharinum and Fagus species are attacked in North America by the Maple Leafcutter (Paraclemensia acerifoliella) that forms a small cocoon in leaves that it skeletonises.

In Australia Case moths and Painted apple moths (Teia anartoides)

Ailanthus altissima is attacked by the Cynthia Moth (Samia cynthia) light green lava, which eats leaves and the Ailanthus Webworm (Atteva aurea) which are olive-brown caterpillars that form web nests in the leaves.

Antirrhinum species are attacked by the Leaf Tier (Udea rubigalis) lava. This caterpillar eats pieces out of leaves and binds them together forming a nest. It is more commonly found in glasshouse culture.

Berberis species may become infested with the Barberry Worm (Omphalocera dentosa). This small caterpillar is black with white spots, up to 14mm long and feeds on young shoots and leaves. It also binds the shoots with a silken thread to form a nest.

Betula species are attacked by the Leaf Skeletonizer (Bucculatrix canadensiella). The small adult moth has brown wings with a whitish underside and its yellow green, 7mm long lava skeletonise the undersides of the leaf turning it brown.

Brachychiton, Senna and feathery-leaved Acacia species are attacked by the Tailed Emperor Caterpillar, particularly in dryer periods.

Catalpa species are attacked Catalpa Sphinx (Ceratomia catalpae). This large yellow and black Caterpillar grows to 76mm long and attacks the leaves.  Large infestations can completely stripped a tree and control is carried out by spraying.

Calendula and Canna species are attacked by the Woollybear Caterpillar (Diacrisia virginica) which has yellow and black lines down its body is up to 50mm long and eats the leaves or flower buds. In Canna species the chewed holes tend to be in a straight line across the leaf.

Celtis species are attacked by the Spiny Caterpillar (Nymphalis antiopa) which is reddish, up to 50mm long and feeds on the leaves at the top of branched in groups.

Cheiranthus species are attacked by the Diamond-backed Moth (Plutella maculipennis) lava, which is a small green caterpillar to 14mm long that feeds on the underside of leaves and may form a shot hole appearance. It forms a small cocoon to pupate in and in cooler climates it may be found in glasshouses.

Cotinus, Fraxinus, Betula, Cornus, Crataegus, Aesculus, Tilia, Acer, Quercus and Populus species are susceptible to attacked by the Oblique-banded Leaf Roller (Archips rosaceana)

Iris and Antirrhinum species are attacked by Verbena Moth.

Picea, Abies, Tsuga and Pinus species are attacked by Budworm commonly found in the northern hemisphere.

Populus and Carya species are attacked by the Red Humped Caterpillar which chews the leaves.

Quercus species are attacked by several caterpillars including Saddleback Caterpillar (Sibine stimulea) and Datana Caterpillar (Datana ministra) that feed on the leaves.

Samanea saman is attacked by several caterpillars (Ascalapha odorata, Polydesma indomita and Melipotis indomita). These caterpillars defoliate the tree but cause no long term problems.

Spiraea, Fraxinus, Betula, Cornus, Crateagus, Acer, Quercus and Populus species are attacked by the Oblique-banded Leaf Roller.

Ulmus, Salix, Crateagus, Tilia, Quercus and Populus species, Pseudotsuga menziesii are attacked by the Gypsy Moth (Porthetria dispar).

Ulmus species are attacked by the Spring Cankerworm (Paleacrita vernata), which chews the leaves during spring and the Fall Cankerworm (Alosphila pometaria), which also eats the leaves during autumn. Ulmus  species are also attacked by several caterpillars including the lava of the Leopard Moth (Zeuzera pyrina) and the Tussock Moth (Hemerocampa leucostigma).

Cultural Control

Small numbers may be removed by hand and squashed while others species such as the Casuarina Caterpillar drop to the ground when disturbed by hitting with a stick or shaking the plant. On the ground they can be squashed or collected and placed in a bucket of soapy water.  All rubbish around plants and glasshouses should be cleared as certain moths overwinter in such places.

Biological Control

There are many natural predators that reduce numbers including birds, lizards, frogs; other predators are wasps, viruses, and fungi.

Chemical Control

The small plant may be sprayed using Pyrethrum-based insecticide to reduce numbers or dusted with an equally environmental friendly chemical. In severe cases crops may be sprayed with Carbaryl.

Note

Always read the label for registration details and direction of use prior to application of any chemicals.

PEST

   NAME

     Thrips (General)

     Various Thrip Species

   ORDER

     Thysanoptera

Description of the Pest

There are many species of thrips that attack living and dead plant material. The winged adults are black, yellow, white or brown with slender bodies and up to 2mm long. The folded fringed wings appear as silvery stripes and the smaller nymphs are difficult to see, but are wingless simular to the adults. Both adults and the first two nymphal stages have rasping and sucking mouthparts.

Thrip species

Boree Gall (Kladothrips species) adults are gall producing thrips that form smooth bubble-like or irregular spiny growths on the leaves. These galls can contain up to 1000 insects that also reproduce inside, and are trapped until the gall dries or splits open. Commonly found in inland areas attacking the phyllodes of Acacia species.

Glasshouse Thrips (Heliothrips haemorrhoidalis) is a slender up to 15mm long with small fringed wings. The adult lays eggs on the underside of leaves where the nymphs emerge as miniature adults but wingless. Then feed on the soft leaves leaving a silvery mottled appearance.

Appearance and Distribution of the Pest

Thrips are found from tropical to temperate regions preferring a cool mild winter followed by a dry sunny spring that produces abundant flowers and new foliage. It is dispersed by flying and can be carries great distances on the wind.

Life Cycle

These insects have a Hemimetabolous life cycle, ie. When the immature nymphs resemble the adults.

The female adult lays her eggs using an oviposit in a slit on flower stems or occasionally leaves. The eggs develop into four nymphal stages. The first two stages occur on the plant and the last two in the surrounding soil or in leaf litter, emerging as adults and flying to reinfect the plant. It takes ten to thirty days to develop from egg to adult depending on the temperature and rainfall. Under opium conditions thrips are produced in plague proportions.

Period of Activity

Thrips are most active during warm dry, calm weather, but dislike the soil to be too dry or wet.

Damage Caused

Thrips congregate inside the flowers damaging the epidermal layer, allowing sap to leak out. This causes the flower petals to become brownish and curl along the margins. They also attack the upper surface of leaves causing a silvery discolouration as they suck the sap. The effect is a reduction in fruit and seed production on the host plant.

Susceptible Plants

Generally many plants species are attacked by thrips including buds, petals and leaves that are soft are at most risk, such as Alyogyne , Baeckea, Hibbertia, Hibiscus and Leptospermum species. There is also a wide range of ornamentals suseptable to attack including apples, pears, citrus, stonefruit, grapes and strawberries.

Buddleja species may be attacked by the thrip (Hercinothrips femoralis).

Cordyline, Agave, Dracaena and Howea species, Ficus elastica are attacked by the Dracaena Thrips (Parthenothrips dracaenae) which feed of the leaves.

Knightia excelsa is attacked by thrips by feeding on the chlorophyll in the leaf causing significant paling of the leaves. Stresses plants are more susceptible and plants rarely die from attack.

Peperomia, Cissus, Tropaeolum and Passiflora species and some fern species are attacked by Glasshouse Thrips which can cause heavy damage in inclosed areas such as a glasshouse.

Watsonia species are attacked by the Gladiolus Thrips (Taeniothrips simplex).

Cultural Control

There is no satisfactory cultural control. Small infestations may be ignored or the plant may be hosed to reduce the numbers. Removal of surrounding leaf litter, weeds and cultivating the soil can also reduce the numbers and disturb the life cycle. Care should be taken not to remove flowering weeds under trees that are in bloom as the thrips may migrate on to the tree, alternatively flowering annuals can be planted under trees to attract the thrips away.

Biological Control

No effective natural control though birds; wasp and other predators eat thrips. Weather conditions such as heavy rain help reduces numbers.

Chemical Control

Thrips can be sprayed with Dimethoate or Maldison at least twice every ten days to kill newly hatched nymphs, but may have a detrimental effect on other insects such as bees.

Note

Always read the label for registration details and direction of use prior to application of any chemicals.

PEST

   NAME

     Budworms

     Helicoverpa species

   ORDER

     Lepidoptera

   FAMILY

     Noctuidae

Description of the Pest

Mature larvae are caterpillars up to 45 mm long; colour varies from yellowish-green to reddish-brown, most with stripes or darker body markings. Female moths have a wingspan up to 40 mm across, are reddish brown in colour; hindwings are pale at the base and dark along the edges.

Moths of Heliothis are very similar to that Helicoverpa armigera (Corn earworm).

Helicoverpa have a spot which is kidney shaped in the centre of the forewing,

The Adults of all species are attracted to lights at night.

                 

The larvae are smooth and vary in colour but have light coloured strips

Life Cycle

This insect has a Holometabolous life cycle, i.e. it has a larval and a pupal stage.

Females lay up to 1000 tiny white eggs, deposited singly, on the young growth of host plants.

Larvae pupate in the topsoil, after feeding for 2-3 weeks; the emergence of adults is triggered by appropriate moisture & temperature conditions during Spring. Long periods of cold and drought can delay the emergence of the adult moths for up to 5 months.

There are two main periods of infestation early summer and autumn.

Distribution of the Pest

Helicoverpa species (Heliothis species) are found throughout Australia.

Larvae have prominent prolegs

Period of Activity

Most active in Spring and Summer, after good rainfall and vigorous plant growth.

Damage Caused

Larvae attack chew on new growth, fruit, seed and flower buds. Fruit and flowers are damaged and yield is reduced. Entry holes in fruit enlarge and become more obvious as the caterpillar matures.

Bud worms which feed inside the flower buds can cause the buds to brown and not open.

Damage to a flower bud

Susceptible Plants

Attacks a wide range of fruiting and ornamentals plants, such as gardenias, carnations, roses, calendula, hollyhocks, snapdragons, etc. This is a major pest of commercially grown tomatoes, beans,

sweet corn, cotton, sorghum and peas.

Pseudotsuga menziesii, Picea, Pinus, Pseudolarix and Tsuga species are attacked by the Spruce Budworm (Choristoneura fumiferana). Symptoms include the new opening buds and needles are eaten by the dark red caterpillar that has a yellow stripe along its side. It is a serious pest to ornamental and forest trees and control is difficult.

Control

Cultural Control

It is difficult to control bud-worms once they enter the fruit or buds so it important to apply clay and pepper sprays or pyrethrum, while the young lava are feeding on the leaves.  Caterpillars may be removed by hand or infested flowers and fruit removed from the plant.

Biological Control

Genetically modified crops have been developed for cotton.

A virus NPV may be commercially available for cotton growers to control Helicoverpa armigera and H punctigera

Helicoverpa armigera & Helicoverpa punctigera), are parasitised by many different insects, including Chaetophthalmus dorsalis flies from the Tachinidae family.

Egg parasites include Trichogramma & Telenomus wasps

Larval parasites include         Micrropilitis demolitor, Netelia producta and Trachnid flies

Larval pupa parasites include Heteropelma scaposum and Lissopimpla excelsa

Pupal parasites include Ichneumon promissorius

Chemical Control

Control needs to occur before the larvae enter the fruit or flowers.

Note

It is your responsibility by law to read & follow the directions on the label of any pesticide

Monitoring

Shake plants twice a week on to a stiff white cardboard, once they start flowering.

Other Common Names; includes

Native Budworm (Helicoverpa punctigera) Tomato grub, Cotton bollworm, Corn ear worm, Tobacco budworm

Amendments by B. Sonsie Dip Hort Sc Burnley

PEST

   NAME

     Two-spotted Mite, Red Spider Mite

     Tetranychus urticae

   ORDER

     Acarina

   FAMILY

     Tetranychidae

Description of the Pest

Also known as the red spider mite. Females are pale green or yellowish, depending on the host plant, and have two dark lateral markings; the mite becomes red in winter, retaining their dark markings. Nymphs are six-legged, with another pair of legs appearing as the mite matures. Males are smaller and narrower. Fully-grown adults are just visible to the naked eye. Two-spotted mites spread by crawling between nearby plants or movement of dead leaves.

Appearance and Distribution of the Pest

Found world-wide; an introduced pest in Australia. They congregate in protected places, such as under bark and at the base of trees, during winter. During spring, they become green in colour, and migrate back into the leaves. During heavy infestations, the leaves may be covered in visible webs, which they spin as they feed. Leaves may eventually wither and fall. Mites can spread via the movement of dead leaves, or in webs that have become attached to birds or large insects. They initially appear on the undersides of leaves.

Spruce Spider Mite (Oligonychus ununguis) is a tiny greenish black adult which lays eggs on twigs where they overwinter. The pale green young spiders suck the sap turning the leaves yellow to brown. Heavy infestations form webbing and the pest is found on Abies and Juniperus species.

Banana spider mite (Tetranychus lambi) is a major widespread pest of bananas.  It differs from two spotted mite by not producing copious amount of webbing.  It is highly active during the dry spring to summer period and with the onset of the wet season mite numbers are reduced.  The warm dry conditions that are created under plastic bunch covers is ideal for building up banana spider mite numbers.

Damage is normally confined to the underside of leaves appearing as rusty patches that coalesce along the leaf veins eventually turning the whole leaf brown-grey before it collapses.  Fruit is damaged, close to the bunch stalk causing the area to become dull red purple-black, which in turn becomes dry then cracks.

  Damage fruit

Control methods include careful water management during dry periods, and the reduction of dust from roadways.  Regular desuckering and leaf trimming of plants will assist with a good coverage when spraying miticides.

Life Cycle

Mites have a gradual metamorphosis, with several nymphal stages. Each female lays up to 100 eggs that hatch in 7-14 days, with several generations appearing throughout the year. Females may become inactive during cold weather.

Webbing         

Period of Activity

The Two-spotted mite is most active in hot dry conditions. Under optimum conditions, the population can double every four days. It produces large quantities of webbing for over-wintering nests. Many plants are only susceptible to this insect when cultivated under glass.

Damage Caused

Adults and nymphs lacerated the undersides of the leaves with there rasping mouth parts, although infestations on both surfaces are not uncommon. Infestations cause leaf mottling leaf fall; premature leaf loss causes loss of vigour and reduces the quality and quantity of future crops. Repeated infestations, year after year, may weaken root growth and kill herbaceous plants.

Susceptible Plants

A wide range of plants are attacked by the Red Spider Mite including annuals, fruit trees and vegetables, ornamental shrubs and trees.

Note

Many plant species are more susceptible to Red Spider Mite when they are cultivated under glass.

Other species of mite that are mentioned below have simular characteristics.

Calluna, Rose, Tropaeolum and Viola and species are infested with the Red Spider Mite (Tetranychus telarius) commonly in greenhouse situations.

Musa species are attacked by two spotted mite and banana spider mite damaging foliage and fruit.

Juglans species can be infested with up to four types of mites including red spider.

Cultural Control

Heavy rain or irrigation can reduce numbers; some plants may benefit from replanting in cooler locations. Generally, however, infested material should be completely removed and destroyed.

Preventative measures such as removing weeds or mulching around trees or shrubs or scrubbing the loose bark of susceptible trees during winter helps reduce numbers. During spring sticky bands can be wrapped around trunks close to the ground to trap the mites.

Biological Control

Natural predators include lacewings, ladybirds and thrips help keep the numbers down. Insecticide-resistant predatory mites (Typhlodromus occidenyalis) are also available commercially to control the Two-spotted Mite only on a large scale, as they require ample mites to survive.

Chemical Control

Spraying should be carried out as a last resort as many predators are killed during the operation and spraying can have the opposite effect by increasing numbers in the long term. Dimethoate will reduce numbers; however, Two-spotted mites are resistant to insecticides in some areas. Dusting with wettable sulphur may also prove effective.

Note

Always read the label for registration details and direction of use prior to application of any chemicals.

PEST

   NAME

     Whitefly, Snow flies

     Various Whitefly Species

   ORDER

     Hemiptera

   FAMILY

     Aleyrodidae

Description of the Pest

This is a small sap sucking moth-like insect up to 3mm long with winged adults that have a covering of fine white powder, hence the common name. The wings are folded flat over the body and males live for one month and females live up to three months. The eggs are laid on the underside of the leaf and the wingless nymphs are immobile, flattened-round scale -like with a fringe of waxy filaments. The nymphs are translucent to greenish, congregating on young plant tissue and both adults and nymphs suck sap and producing honeydew.  

There are several species such as Ash whitefly (Siphoninus phillyreae), Tobacco whitefly (Bemesia tabaci), Silverleaf whitefly and Spiralling whitefly (Aleurodicus disperses)

Greenhouse whitefly (Trialeurodes vaporariorum)

This species of whitefly normally grow to 2mm long with two pairs of wings. Their colour is due to a covering of a fine white wax and the insect has a white-moth appearance. If disturbed the insects swarm and resettle on the plant quickly. The first nymphal stage is mobile and the later stage is scale-like with fine waxy marginal hairs. These nymphal stages produce honeydew, which encourages sooty mould. It is a persistent pest commonly found in glasshouses.

Adult                   Appearance under the leaf

The Hakea Whitefly (Synaleurodicus hakeae) is a small, moth-like up to 0.15mm wide with wings that have a powdery coating and produce flattened scale-like nymphs. Both adult and nymph gather together in colonies and suck sap.

Appearance and Distribution of the Pest

The eggs are laid during the spring and the adults tend to stay on the underside of the leaf until disturbed, when they fly in mass and may infect other plants. Many plants are only susceptible to this insect when cultivated under glass.

Life Cycle

This insect has a Hemimetabolous life cycle, ie. When the immature nymphs resemble the adults.

White flies have a gradual metamorphosis, egg and four nymphal stages. One generation occurs from three to eight weeks and is dependant on the current weather. Hundreds of eggs are deposited on the underside of leaves in arch or circles each with a short stalk.

Eggs laid in a pattern      Eggs laid in a pattern

After hatching the first nymphal stage wanders around on the leaf surface for several days. Then selects a place to suck sap where it goes through all nymphal stages emerging as an adult after the fourth stage.

Period of Activity

This peat is found from tropical to temperate regions and is most active during warm weather. It is difficult to predict an infestation, as some years it is severe and other years it is absent. In glasshouse conditions it is often a problem and may extend outside the normal period of activity. They overwinter in the egg stage or find sheltered places to hide.

Damage Caused

Affected plants have leaves with yellowish to white mottling on the upper surface or with shiny secretions on new shoots or on the underside. Heavy infestations cause leaves to wilt and sooty mould to appear on the honeydew. Plant looses vigour and in some cases die.

                  Tagetes erecta

Susceptible Plants

Whiteflies attack a wide range of plants affected by this insect, including Abutilon, Boronia, Hibiscus and Fuchsia species. Citrus, Vegetables, Ferns and certain weed species are venerable. Australian native plants are also attacked, such as the Hakea species.

Greenhouse whitefly (Trialeurodes vaporariorum) attacks a wide range of ornamental plants, weeds and vegetables including; Phaseolus (beans), Lycopersicon  (tomatoes), potatoes, Cucumis (cucurbits), Lactuca (lettuce), Dendranthema (Chrysanthemum), Dahlia and Hibiscus species.

Several ferns, including Adiantum, Asplenium, Davallia, Nephrolepis, Onychium, Platycerium and Pteris species are attacked with nymphs congregating on the underside of the fronds, normally causing little damage.

Rhododendron species are attacked by the Rhododendron White Fly (Dialeurodes chittendeni) causing yellowish mottled appearance on the upper surface of the leaf.

Cultural Control

It is difficult to control with out the application of chemicals, though strong jets of water greatly disturb the colonies. Companion plantings with basil or other aromatic plants deters white flies or spray the plants with onion-garlic spray.

In an enclosed environment sticky fly paper can reduce numbers. When the nymphal stage is found an application of white oil will reduce numbers.

Biological Control

A parasitic wasp (Encarsia Formosa) attacks nymphal stages reducing numbers. Other predators include small birds, spiders, ladybirds and there lava, hover flies, damsel flies and mantids.

Chemical Control

Plants may be sprayed with Dimethoate, permethrin, bifenthrin or pirimiphos-methyl, but some insects have immunity to chemicals. The pest may also be sprayed with a mixture of white oil and nicotine sulphate or pyrethrum.

Note

Always read the label for registration details and direction of use prior to application of any chemicals.

Note: Plants affected by this pest are Deer Resistant plants not the susceptible plants.

 

PEST

   NAME

     Deer

     Cervus species

   ORDER

     Artiodactyla

   FAMILY

     Cervidae

 

 

Description of the Pest

There are two species of the deer in North America, the Whitetail (Odocoileus virginianus) and the Mule deer (Odocoileus hemionus) with several regional variations such as the Pacific coastal Blacktail (O.h. columbianus) which is regarded as a sub-species of the Mule deer.

 

The Whitetail on average grows to 112 cm (44in) tall and 180 mm (70 in) long and weigh 68 kgs (150lbs). The fir colour varies according to its environment but generally it is reddish-brown during summer and grey-brown in winter with a pure white underside on its tail. When the tail is erect it is known as the "white flag". Its antlers consist of two main beams from which the points emerge.

 

The Mule deer grow to 105 cm (42 in) tall and are up to 200 cm (80 in) long with the adult buck weighing up to 137 kgs (300 lbs) and the does up to 80 kgs (175 lbs). The fir is generally tawny brown during summer and during winter it has a heaver grey-brown to blue-grey coat with a small white tail that is tipped in black. The other distinguishing features are its ears that are up to 300 mm (1 ft) long (mule-like) and its antlers, with the two beams that are forked into smaller beams, which inturn fork again and again.

 

The Blacktail deer (Pacific coastal Blacktail) grows to 97 cm (38 in) tall and is up to 105 cm (60 in) long and weighs on average 73 kgs (160 lbs). The fir is generally tawny brown during summer and during winter it has a heaver grey-brown to blue-grey coat with a tail that is dark brown at the base then changing to black for 50% of its length. The antlers consist of two beams that are forked into smaller beams, which inturn fork again and again.

 

Appearance and Distribution of the Pest

The Whitetail deer are found throughout eastern United States, on the coast and inland but are not commonly seen in California, Utah or Nevada. They do not migrate but congregate together (yard up) during winter and feed in a part of their existing territory.

 

The Mule Deer are found in the western part of North America from South eastern Alaska to Mexico and from the Pacific coast to Texas. They migrate from highland mountain meadows to southern or lower snow free forested valleys during winter.

 

The Blacktail deer are found on the Pacific coast from Alaska to northern California. There is both resident and migratory Blacktails. The  migratory Blacktails move southwards during late autumn at the first sigh of snow or heavy sustained rain and the resident Blacktails seek cover their existing territory amongst woodlands during the winter months.  

 

Life Cycle

All Deer breed from autumn to early winter and the does give birth from late spring to early summer.

 

Period of Activity

Deer are most active from spring to autumn but can be troublesome during winter when the feed is scarce. In some regions urban landscapes become the major food source both in summer and winter.

 

Damage Caused

Browsing deer will feed on almost any plant and is most commonly noticeable during spring feeding on the new growth or twigs and stems leaving a shredded appearance. Deer also rub their antlers against trees damaging bark and snapping off small branches, this action also incurs damage under hoof as plants, lawns and garden structures are trampled on.

 

Susceptible Plants

Some plants are more palatable to deer but when a deer is hungry or during drought conditions there are no "Deer Proof" plants. There is a range of plants that have a bad taste and are not destroyed and are regarded as (deer resistant plants). Deer resistant plants are the plants that are attached to this file not the susceptible plants.

 

Cultural Control

There are many cultural controls that have been tried to move browsing deer such as frightening them with strobe lights, pyrotechnics or tethered savage dogs. These actions are only temporary and may cause more trouble as the stampeding animals move off. Fencing and netting can be an effective method of discouraging hungry deer from gardens but may be expensive on a large scale and require maintenance. There are several types of fences which include conventional 2.2m (8 ft) deer-proof woven wire fences or single-wire electric fences and slanted deer fences. Plant selection can also be effective, by using less desirable plants (deer resistant plants) as an outer border to the more desirable plant species and  thus discouraging the deer to enter the garden. Hedges and windrows of less desirable thorny plants can also be a deterrent to browsing deer.

 

Chemical Control

There are two main types of repellents contact and area. Contact repellents are applied directly to the plants and deter deer with a bad taste or smell. They can be applied by rubbing or spraying on to the plants and commonly used in an egg mixture. The commercial products have proven to work better than home remedies which include soap or chilli mixtures and hanging bags of human hair.

Area repellents rely on an offensive odour and are placed around areas that are frequently visited.

 

Contact your local distributor for available types and application.

DISEASE

   NAME

     Fungi (General)

     Various Fungal species

Description

A fungus is a plant that lacks chlorophyll and conductive tissue. Generally they are made up of branched threads called 'hyphae' and collectively form a vegetative body called 'mycelium'. The fungus is small but the fruiting bodies can become very large up to 600mm across such as bracket fungi or mushrooms. Common fungi are mould and mildews. problem that attacks the roots causing them to rot.

Fungus can reproduce many ways but primarily it is asexually, simular to cuttings of a plant and often occurs with minute portions of the mycelium (spores) separating. The spores can be arranged in a structure such as a sporangia or pycnidia or develop without an enclosed structure called a "conidia". Either way the fungus propagates very rapidly.  Sexually reproduction occurs when two nuclei unite and form sexual fruiting bodies (zygospore).

Strelitzia reginae flower

Symptoms

Fungus attacks all the above or below ground level parts of the plant living within the tissue of the plant and are very small and not normally detected until the fruiting body appears. However parasitic types such as powdery mildew or rust are visible on the outer surface of the plant.

Fungi hyphae may be divided by cross walls and known as "septate" while others with no cross walls are known as "nonseptate". These are the fungi responsible for cell leakage as in rot.

Back Mold (Chalariopsis thielavioides) affects understocks of grafted Rosa species by inhibiting the development of callus. It is whitish-grey maturing to black and can be found in the pith of the rose stem.

Black Root Rot (Chalara elegans).This recently introduced fungal disease in Australia (1993) affect plants by blackening the root systems and turning leaves yellow or purple. It is difficult to identify specifically as other pathogenic root diseases and nutritional deficiencies have simular characteristics.  

The asexual spores are dispersed by wind or water. It is also transmitted on insects and in contaminated growing media or plants preferring humid moist conditions.

This fungus affects a wide range of ornamental plants including; annuals, perennials and shrubs. Examples are Begonia, Boronia, Camellia, Cyclamen, Fuchsia, Gerbera, Grevillea, Impatiens, Pansy, Petunia, Rosa species and Snapdragon.

Black Stem Rot (Pythium splendens) normally is a rot that occurs in cuttings turning the stem progressively black and shrunken. The leaves fall and the plant becomes stunted, eventually dieing.

Bleeding Necrosis (Botyosphaeria ribis) attacks and kills the inner wood causing the bark to split open and bleed sap giving it an oily appearance.

Blight (Endothia parasitica) is a serious pest of Castanea species, entering the twigs and small branches, and then progressively travelling throughout the tree killing it. It may form cankers on the base of the trunk or in the dead branches above with the amber coloured fruiting bodies pushing there way through the bark.

Copper Web ((Rhizoctonia crocorum). This fungal disease appears in defined patches causing the corms in the centre to become a black powdery mass. Corms on the outer ring of the patch that are partially infected forming a felty mass of violet threads on the corm scales. These threads extend into the soil and large sclerotia forms in the soil and on the corms. Healthy corms become infected from contaminated soil that contains mycelium and sclerotia.

Dry Rot (Phyllosticta concave) forms small circular spots that increase to a diameter of 30mm, and then becomes sunken as the cells collapse. The infected area develops minute black fruiting bodies.

Dutch Elm Disease (Ceratocystis ulmi) is a serious fungal problem of Ulmus species that initially causes yellowing then wilting of the leaves that turn brown and die. This may be seen on certain branches of the tree and on inspection under the bark the sapwood reveals brown streaks. A cross section of the affected branch displays round spots that are dark brown. This infection normally spreads quickly throughout, killing the tree in one to two seasons.

Dieback in Camellia (Glomerella cingulate) is a pathogenic fungus that infecting existing wounds such as leaf scars or mechanical damage, forming a sunken area (canker) that spreads around the stem causing die back. The affected plant has new shoots that are brown-black and the tips curl, forming a 'Shepard's Crook' appearance. The leaves also die but are persistent on the plant and the spores are found in soil or on other infected plants.

Curvularia Leaf Spot (Curvularia species) in Turf Grass. This is normally a secondary weak fungal infection that forms spots on the leaves that lengthens turning the leaves greyish. The leaf shrivels then dies and infected areas appear as weak patches in the turf. Preventive measures include minimising leaf wetness and excessive use of nitrogen fertiliser.

Fairy Rings Blue Couch     

Fairy Rings are a fungal problem in Turf Grass and is caused by several species including (Lycoperdon species), (Marasmius species) and (Tricholoma species). Rings appear in the turf as fruiting bodies or dead grass and as lush green foliage. The mycelia expand radially in the turf feeding on soil nutrients and organic matter with water present.

Under severs conditions the mycelia consume all available nutrients resulting in the death of the turf. Lush turf can result from a less developed infection, where the decomposing hyphal releases nitrogen. This available nitrogen may be beneficial to the turf but some forms of nitrogen are detrimental.

Leaf Blister (Taphrina coerulescens) appears as yellowish circular raised areas on the upper side and depressions on the underside of leaves, up to 15mm across. As the fungus spreads the leaf dies but remains attached to the tree and this infection is commonly found on Quercus species..

Leaf Blotch (Guignardia aesculi) forms small or large water soaked spots that are reddish with a bright yellow margin and form black fruiting bodies in the centre. The affected leaf and petiole have a scorched appearance before falling, found on Aesculus species

Grevillea robusta     Leaf Scorch

Leaf Scorch (Verrucispora proteacearum) is a fungal disease that infects leaves causing large parts of the leaf to turn grey-brown, giving the appearance that it has been singed by fire. Black fruiting bodies appear on the affected areas and the leaf soon withers then dies. New, mature leaves are affected during very wet periods towards the end of the branches and Grevillea and Hakea species are susceptible.

Melting Out (Helminthosporium vegans) forms bluish black spots with straw coloured centres on the leaves and may be found on the sheath, encircling it causing Foot Rot. It infects grasses particularly Poa pratensis. There is another fungus that is simular Helminthosporium Blight (Helminthosporium dictyoides) that infects Poa, Festuca and Agrostis species.

Pad decay (Aspergilus alliaceus) infects Cereus and Opuntia species and occurs at during periods of high temperature.  The yellow spores at the epidermal layer through wounds and germinate on mass causing the area to become soft and spongy. An anthracnose called Shot Hole is a similar forming brownish spots the turn grey, and then black destroying pads. Control methods include physically removing damaged pads and allowing the Sun to heal wounds.

Potato Gangrene (Phoma foveate) is a soil borne fungus that infects the roots during harvest primarly through wounds and develops during storage. The potatoes rot from the inside forming rounded depressions on the surface and have a strong odour of rotten fish.

Root Rot Fungi (Phymatotrichum omnivorum) and (Pellicularia filamentosa) cause the roots to rot and the plant suddenly wilts then dies.

Root Rot (Pythium debaryanum) forms water soaked dark brown streaks that affect all parts of the plant causing wilting then dieing. It infects Ranunculus species, it also infects cactus species by forming brown spotting and wilting that appears at the base of the plant then extends towards the top. It quickly spreads from plant to plant in collections and is controlled by avoiding over watering, excessive humidity and are using a sterilised soil when potting up.

This fungus also is responsible for damping off of seedlings in a glasshouse environment.

Spring Dead Spot     

Spring Dead Spot (Leptosphaeri species) is a fungal disease that infects Couch Grass. It first appears during autumn as pale bleaches areas up to 500mm (20in) wide and persists throughout winter. In spring the affected areas do not recover or recover slowly and on inspection the roots or rhizomes are rotted. Runners from the surrounding healthy turf will help with recovery and all signs of the problem disappear by mid summer.

Cactus species      Pachypodium species

Stem Rot (Helminthosporium cactivorum) forms well defined yellow lesions that mature into soft dark brown rot. It commonly infects Cactus species entering through the stomates or wounds. Heavily infected plants collapse and die.

Stem Rot or Basal Rot (Pellicularia rolfsii) is a soil borne fungus that infects the stem root junction and extends into the leaves. In orchids the leaves become discoloured, dry and detach from the base which is covered in a fungal growth that produces sclerotia. The sclerotia is whitish to yellow then becoming dark brown and can be viable for up to four years.

White Mold  (Ramularia desta f. odorati) occurs on both sides of the leaf and looks simular to powdery mildew but forms faint dull, reddish brown elongated spots on the leaf that may be depressed or along the margin where they have a watery appearance. Tufts of hyphae develop in the stomates.

Wilt (Ceratocystis fagacearum) causes leaves to curl then turn brown and the sap wood may also turn brown or black. Heavy infection may kill a tree within two seasons and is found on Quercus species and other ornamental trees.

Witches Broom may be a fungal problem that causes a proliferation of small axillary shoots to appear at the end of the branches. Little is known about this problem, though it affects a wide range of plants including Eucalyptus, Leptospermum and Pinus species.

Source and Dispersal

Fungus is found in the soil or on other infected plants and after releasing the spores, they are dispersed by wind or are transmitted in infected stock, insects and with splashing water.

Wilt is transmitted by infected root stocks, several species of insect and contaminated tools.

Dutch Elm Disease is transmitted by bark beetles such as (Scolytus multistriatus) and (Hylurgopinus rufipes). These beetles deposit eggs in the sapwood where the lava tunnel and pupate. The emerging beetles tunnel the bark and carry the fungus to fresh feeding sites on the tree. Infected beetles may also be transported to fresh sites in waist material.

Favoured Conditions

Prefers cool moist conditions with temperatures from 10º to 25ºC and is more common from autumn to spring when it is wet.    

        

Affected Plants

A wide range of plants and all parts can be infected by various fungal diseases. Bleeding Necrosis is found in Liquidambar species and Stem Rot or Dry Rot infects Cactus species such as Opuntia and Pelargonium.

Abies species are infected by several fungi that cause Leaf Cast which turn the needles yellow to brown then fall prematurely.

Abutilon species are infected by the Stem Rot (Macrophomina phaseolin) affecting the lower stems and is not commonly seen.

Achillea, Cuphea, Leucanthemum, Euphorbia species are infected by the Stem Rot (Pellicularia filamentosa) which enters through the roots and rots the base of the stem.

Alternanthera species are infected by the Leaf Blight (Phyllosticta amaranthi) which forms small brown spots on the leaves causing them to curl and die.

Aloe, Astrophytum, Copiapoa, Echinocactus, Espostoa, Ferocactus, Gymnocalycium, Kalanchoe and Schlumbergerera species are infected by Bipolaris Stem Rot (Bipolaris cactivora). This infection affects many cacti species causing rot in the stems with a blackish appearance.

Amelanchler is affected by the Witches Broom (Apiosporina collinsii).

Antirrhinum species are infected by the Blight (Phyllosticta antirrhini) that forms light brown spots on the upper-side of the leaf and on the stem. As the spots enlarge they turn greyish with black fruiting bodies in the centre, then become brown and killing the affected areas.

Begonia species are infected by the Stem Rot (Pythium ultimum) turning stems black then becoming soft and causing the plant to collapse. This is the same fungus that causes Damping-off.

Betula species are affected by the Leaf Blister (Taphrina bacteriosperma) which curls the leaves and forms reddish blisters.

Chamaedorea and other cain-like species are infected with Gliocladium Stem Rot (Gliocladium vermoseni) which forms a dark basil stem rot generally on damaged plants and produces orange-pink spores.  The mature leaves are first affected and eventually the stems or cains rot and die.

Crocus and Gladiolus species are infected by the Dry Rot (Stromatinia gladioli), which causes lesions on the corms and rots the leaf sheath.

Crocus, Iris, Tulipa, and Narcissus species are infected Copper Web ((Rhizoctonia crocorum).

Dianthus species are infected by Phialophora Wilt (Phialophora cinerescens) that causes the leaves to fade and plants to wilt. There is obvious vascular discoloration which is very dark. It is not found in Australia.

Erythrina x sykesii may be infected by the Root Rot Fungi (Phymatotrichum omnivorum).

Fern species are infected by Tip Blight (Phyllosticta pteridis). This blight produces ash-grey spots with purple brown margins and the fruiting bodies appear as black pimple like spots.  It is transmitted by air or moisture and in infected fronds become brown and die.  Control methods include sprang fungicide on leaves or reducing humidity and avoid wetting the fronds.

Forsythia species are infected by Stem Gall (Phomopsis species). It forms rounded growths along the stems causing them to die and look unsightly.

Gladiolus species are infected by Penicillium Rot of Corms (Penicillium gladioli). This disease forms deeply sunken reddish brown areas that become corky and produce a greenish fungal growth.

Hedera species are susceptible to several Fungal Leaf Spots including (Glomerella cingulate), (Phyllosticta concentrica) and (Ramularia hedericola). All of which cause yellowish spots that develop into dry brown blotches that kill the leaf.

Larix species are susceptible to Leaf Cast (Hypodermella laricis). This fungus attacks the needles and spur shoots turning them yellow at first then brown after which small black fruiting bodies appear on the leaves during winter.

There are several other fungi including (Cladosporium species) and (Lophodermium laricis) cause leaf blight or leaf casts.

Orchids such as Cattleya, Cymbidium, Cypripedium, Dendrobium, Epidendrum, Oncidium, Paphiopedilum, Phalaenopsis and Zygopetalum species are infected by Phomopsis Rot (Phomopsis species). This fungal problem forms a firm brown rot that appears on the leaves, pseudobulbs and rhizomes. The affected areas have yellow margins and the centre is covered in tiny black specks (fruiting bodies). Cattleya species are particularly susceptible. These plants are also infected by Psudobulb Rot (Mycolleptodiscus coloratus implicated). Dark spots appear on the pseudobulbs eventually causing extensive rot and killing the bulb.

Palms are infected by the fungus Butt Rot (Ganoderma sulcatum). The fungus entered the lower trunk normally as a result of mechanical damage (lawn mower). Symptoms include stunting of new growth and yellowing of the lower leaves. Fruiting bodies become evident at the base of the trunk. There is no effective control method and replanting in infected soil should be avoided.

Kikuyu Yellows     

Pennisetum clandestinum (Kikuyu) is susceptible to Kikuyu Yellows (Verrucalvus flavofaciens), thisis a water mould that infects the roots and causes them to rot. The infection extends up the stem and onto the leaves with yellow discolouration and can be limited to a small or large area up to 1m (3ft) wide.

It is found in warm temperate to sub tropical regions and dispersed in infected soil or plant material. There is no chemical control, nitrogen fertiliser masks the symptoms and complete fertiliser encourages stronger roots to fight the disease.

Pittosporum, Antirrhinum, Aquilegia, Echinops and Orchid species are infected by the Stem Rot or Basal Rot (Pellicularia rolfsii) commonly in the northern hemisphere and preferring humid glasshouse conditions.

Solidago species are infected by the fungal Scab (Elsinoe solidaginis) which covers the leaves and stunts the growth of the plant. Young plants may be killed.

Trillium species are infected by the stem rot (Pellicularia rolfsii) and ( Ciborinia trillii). This normally occurs in wet soils and is detrimental to the plants life.

Tsuga species are infected by Sapwood Rot or Butt Rot (Ganoderma lucidum) and (Coniophora puteana), which attacks the sapwood close to the bark, towards the base of the tree. Commonly killing the host.

Tulipa species are affected Blue Mold (Penicillium species) and the fungus (Rhizopus stolonifer) causing rot in the bulbs.

Vinca species are infected by the soil born Root Rot (Pellicularia filamentosa) which rots the stems and roots.

Viola species may be infected with the Scab (Sphaceloma violae) which attacks all parts of the plant including the seed capsule forming yellowish spots that turn brown and in leaves fall out. Stems and petioles can be girdled killing the upper part.

Viola species are also infected with the Stem Rot (Myrothecium roridum) which attacks the stems at ground level causing them to become dry and brittle. The leaves show symptoms by turning purplish-black and this fungus also infects Alcea and Antirrhinum species.

Non-chemical Control

Generally remove and destroy any infected plants or plant parts, when replanting, avoid using susceptible species for 3 years.  When growing crops space the plants to reduce the humidity and airflow and cultivate the soil to increase the drainage.  Remove weed growth from around the susceptible plants.

Avoid over watering the surrounding soil which encourages fungal development. In the case of trees remove any infected branches and heavily infected trees should be cut down and removed. This infected material should be disposed or burnt. Damaged trees should have the wounds dressed and sealed as a preventative measure particularly for Dieback in Camellia.

Deter Potato Gangrene by planting clean stock and be careful not to damage the crop when weeding. When harvesting the tubers choose a dryer period and be careful not to damage them.

     Fairy Rings

Fairy Rings in Turf are difficult to control and may appear or disappear sporadically. Cultural practice such as minimal thatch build-up, regular aeration and a reduction of organic matter spread on the turf will reduce infection.

Chemical Control

No suitable fungicides available, though drenching or spraying the soil with the fungicide dichloran helps control soil born fungi.

Note

Always read the label for registration details and direction of use prior to application of any chemicals.

DISEASE

 

   NAME

     Rust (General)

     Various Rust Species

 

Description

Generally this fungal problem involves many species causing a range of symptoms, but generally produces pustules that release reddish - brown spores. Most fungus is specific to its host and normally will not infect other plant species.

 

Pustules

 

Symptoms

The upper leaf surface develops red, brown or yellow areas and the underside produces bright yellow to orange spores that correspond to the patches above.  Infested leaves become brown in patches, fall prematurely and flower and fruit may also be infected.  This overall, results in a loss of vigour and in small plants may lead to death.  

 

Pelargonium x hortorum

 

Myrtle Rust (Puccinia psidii) This fungal disease infects plants in the Myrtaceae family and was only recently detected in 2010 and has since spread across eastern Australia from the Northern Territory to Queensland, NSW, Victoria and Tasmania. This rust attacks soft and actively growing foliage or shoots with varying symptoms. It normally starts as small purple spots on the leaves from which spores form in yellow pustules that fade to grey as the infection matures and can merge creating leaf distortion and death of the plant. 

The life cycle starts when the powdery yellow spores are distributed by wind to other plants where they germinate and start to grow by piercing the plant cells to obtain nutrients. Germination occurs in dark moist positions with a temperature between 15° to 25°C and the new pustules can release spores in 10 to 12 days, (spores remain viable for 3-months). The spores spread rapidly by wind, water, insects or animals. They are also distributed by plant material, clothing, shoes and vehicles.

 

 Puccinia psidii

 

 

Needle Rust (Melampsora farlowii) infects the new leaves turning them to yellow and fall from the shoot giving the branch a scorched appearance. The fruiting bodies are found on the underside of the leaf and is waxy-red.

 

 

Rust in Poplar (Melampsora species). A fungal problem involving at least two species (Melampsora medusae) and (Melampsora larici-idaei).

The upper leaf surface becomes flecked with yellow to light green and the underside produces bright yellow orange spores that correspond to the patches above.  Infested leaves become brown in patches, fall prematurely and shoots may die back as a result of not being hardened off to the elements.  This overall, results in a loss of vigour and in small plants may lead to death.  

The source of the fungus is from other infected plants or fallen leaves and is dispersed by wind.

Host plants include Lombardy Poplars particularly Populus nigra 'Italica' and cottonwoods.

 

 

White Rust (Albugo candida) forms snow white pustules that contain colourless spores that turn yellow then brown and are found on the underside of leaves.

 

White Pine Blister Rust (WPBR) is caused by the fungus (Cronartium ribicola). It is a obligate parasite requiring a living host to survive. The life cycle requires two host species with part of it life on the Pinus species and the other part on Ribes species. First cankers or sores appear on the Pinus species realising spores that land on the Ribes species infecting it. The infection produces a different type of spore that land on the needles and growing branches of the Pinus species and eventually forming cankers. The spores are spread by wind and prefer cool moist conditions. Symptoms include brown spots on the needles and the appearance of dead branches in the crown. Cankers will also appear on the trunk and it tends to attack young trees. Control methods include removal of Ribus species in the affected areas and breading naturally resistant Pinus species.

 

The Rust (Endophyllum sempervivi) affects Sempervivum species by infecting the young leaves and eventually the crown. The mycelium then travels to the roots and extends into any off shots. Leaves that are infected turn yellowish, grow longer and are thin. Persistent infection may kill the plant.

 

Source and Dispersal

The source of the fungus is from other infected plants or fallen leaves that contain the fruiting bodies and is dispersed by wind.

 

Favoured Conditions

Generally rust is more prevalent during summer, preferring warm humid conditions and particularly when the leaves are damp.

 

Affected Plants

A wide range of ornamental annuals, perennials, ferns, trees, shrubs including, Hibiscus species that are infected by Kuehneola malvicola predominantly in southern USA.

 

Abies species are infected by many types of rust including (Milesia fructuosa) and (Uredinopsis mirabilis).

 

Abutilon, Phymosia and Alcea species are infected by the rust (Puccinia heterospora).

 

Alnus species are occasionally infected with Leaf Rust (Melampsoridium hiratsukanum) which forms yellowish pustules on the leaves that develop turning the leaf brown.

 

Amelanchler species and Calocedrus decurrens are infected by several rust species including (Gymnosporangium libocedri).

 

Antirrhinum majus (Snapdragon) is infected by the rust (Puccinia antirrhini). This fungal problem that infects the epidermal layer on the leaf underside, forming pale green areas that are raised and split open revealing reddish brown spores that have a dusty appearance.  

As the infestation grows, concentric rings of spore pustules appear around the original infection.  The corresponding position on the upper leafs surface turns yellow eventually causing the leaf to wilt and die.  The infestation is not restricted to the leaves; all above ground parts of the plant are susceptible and infected plants transmit the fungus dispersing it by wind.

Infected plants should be removed and destroyed.

 

Anemone and Prunus species are infected by the rust (Tranzschelia pruni-spinosae) that stimulates abnormal growth in the plant during spring.

 

Aquilegia, Anemone, Delphinium and Clematis species are infected by the Rust (Puccinia rubigo-vera var. agropyri).

 

Arctostaphylos manzanita is infected by the rust (Pucciniastrum sparsum) occurring in coastal regions but is not normally detrimental to the plant.

 

Artemisia species are infected by the rust (Uromyces ari-triphylli) which is a systemic disease that is transmitted through seeds. It causes the leaves to turn yellow then die and can infect all parts of the plant except the roots.

 

Bambusa species are infected by the rust (Dasturella divina) which forms elongated brownish strips on the leaves.

 

Berberis species may be infected by the Rust (Puccinia graminis) that forms orange spotting on the leaves. It certain regions plants infected with this rust must be removed and destroyed to avoid infecting neighbouring agriculture crops.

 

Betula species may be infected by Leaf Rust (Melampsoridium betulinum) that forms reddish-yellow spots on the leaves and heavy infestation can defoliate the tree. The host tree changes to Pseudolarix species during the sexual stage and causes blistering of the leaves.

 

Calendula species may be infected by the Rust (Puccinia flaveriae).

 

Callistephus and Solidago species may be infected by the Rust (Coleosporium solidaginis) which forms bright yellow spots particularly on new foliage or young plants.

 

Canna species may be infected by the rust (Puccinia Thaliae).

 

                  Canna indica

 

Centaurea species are infected by the rust (Puccinia cyani) and (Puccinia irrequisita) which can cover the stems and leaves.

 

Cleome species are infected by the rust (Puccinia aristidae) but rarely requires control.

 

Dianthus species are infected by the rust (Uromyces dianthi) which forms powdery brown spots that appear on both sides of the leaves. The leaves curl and die and the plant becomes stunted. This is a common problem that occurs when grown in a protected enclosure (hot house).

 

Ficus species are infected by the rust (Cerotelium fici) which forms small brown spots, and causes the leaves to turn yellow then fall prematurely.

 

Fuchsia species are infected with (Pucciniastrum epilobii). This fungus caused purplish red blotches on the upper leaf surface, that become dry in the middle and result in a brown patch with purple edges.  On the underside of the leaf, corresponding to the patches, yellow orange spores form.  Heavily infected leaves become yellow and drop prematurely.  This leads to a loss of vigour in the plant and infected plants transmit the fungus.  

Certain cultivars are more susceptible than others, particularly 'Orange Drops' and 'Novella'.

 

Hydrangea species is infected by (Pucciniastrum hydrangeae) causing yellowish brown pustules to appear on both sides of the leaf. The leaf becomes dry and brittle.  

 

                  Iris species

 

Iris  and Dietes species are very susceptible to the rust (Puccinia iridis). Leaves form rusty red powdery spots that enlarge. They are appear on both sides of the leaves causing the surrounding area to turn pale yellow then brown and the black spores appear soon after, overwintering on dead infected leaves. Plants may be heavily infected but normally survive attack.

 

Larix species are infected by several Needle Rusts including (Melampsora paradoxa), (Melampsora medusae) and (Melampsoridium betulinum). The fungi attacks the needles predominantly towards the branch tips turning them yellow and eventually killing them . The underside of the leaf develops pale yellow fruiting bodies.

 

Lupinus species are infected by three species of rust including (Puccinia andropogonis var onobrychidis).

 

Malus andChaenomeles species may be infected by the rust (Gymnosporangium juniperi-virginianae) or (Gymnosporangium clavipes) which forms brown or bright orange spots on the leaves or twigs and can defoliate the tree. Juniperus virginiana and Mespilus germanica may also be infected by rust.

 

Mathiola and Arabis species are infected by White Rust.

 

Pinus species are infects by the Comandra Blister-rust (Cronartium comandre).

 

    

Plumeria rubra                           Leaf upper surface                    Leaf underside

 

Plumeria species are susceptible to the rust (Coleosporium plumeriae). Leaves and flowers may be infected with the underside forming bright yellow pustules and causes premature leaf or flower drop.

 

Populus nigra 'Italica' is infected by the rust (Melampsora species) which forms pustules to form on the leaves turning them brown and causing premature leaf drop.

 

Rhododendron and Tsuga species are infected by the rust (Pucciniastrum vaccinii) and is commonly found in nursery stock, spreading rapidly. Tsuga species are also infected by Needle Rust.

 

Ribes species are infected by the rust (Cronartium ribicola). This leaf rust appears on the underside of the leaves (preferably older leaves) forming dusty brown pustules and is a serious problem. This rust only appears when White Pine (Pinus strobes) grows near where the alternate stage of the fungus occurs.

 

Rudbeckia species are infected by several species of rust including (Puccinia dioicae) and (Uromyces rudbeckiae).

 

Salix species are infected by four types of (Melampsora species).

 

Senecio, Bellis and Calendula species are infected by the rust (Puccinia lagenophora) which forms blister-like pustules that release brown spores.

 

Sorbus aucuparia is affected by several rust from the (Gymnosporangium species) causing circular yellow spots, that appear on the leaves during summer and develop into orange cup-shaped fruiting bodies.

 

Trillium species are infected by the rust (Uromyces halstedii) that damages the leaf surface.

 

Festuca arundinacea      Rust

 

Turf Grass are susceptible to rust (Puccinia species) and (Uromyces species), causing yellow flecks to appear on the stems and leaves. These markings enlarge before the pustules form and in severs cases the lawn has a yellow, red or brown appearance.

The infection appears from spring to summer under humid low light conditions and turf that is under stress or with excessive nitrogen in the soil is more susceptible. Many species may be infected including Lolium perenne (Perennial Ryegrass) and Poa pratensis (Kentucky Bluegrass).

 

                  Rust on Perennial Ryegrass

 

Viburnum species are mildly affected by two types of rust (Coleosporium viburni) and (Puccinia linkii).

 

Viola species are infected by the rust (Puccinia violae) which forms green spots on the underside of the leaves. It is not commonly seen on cultivated plants.

 

Non-chemical Control

Cut off and destroy any infected branches, fallen leaves and remove heavily infected plants. Improve the culture by, pruning to improve air circulation, allow space between plants and avoid over crowding.  Avoid planting susceptible species.  Plants that are infected with a systemic form should be removed and destroyed

 

Chemical Control

Not possible to spray large trees but young plants may be treated with a protectant fungicide such as wettable sulphur. In a domestic garden small plants such as Fuchsia species may be sprayed with a protectant chemicals as symptoms appear, aided by the removal of existing infected leaves.  Under commercial conditions stock may be sprayed with a fungicide such as oxycarboxin.

Note

Always read the label for registration details and direction of use prior to application of any chemicals.

DISEASE

   NAME

     Leaf Spot (General)

     Various Leaf Spot Species

Description

There is a wide variety of fungal leaf spots that infect perennials, shrub and trees. Some are specific to the host while others can affect a range of plants.

Symptoms

Generally light brown to purplish or blackish spots appear on the leaf and form concentric rings of fruiting bodies. The spots may leave holes, perforating the leaf or expand with pale green to yellowish margins and when the holes merge the leaf normally dies. There are many different types of leaf spot, some are discussed below.

Alocasia species     

Alternaria Leaf Spot (Alternaria nelumbii) forms a small reddish brown spots that are boarded in light green, and as they develop in size the leaf curls and dies from the margin inwards. Normally occurs on Nelumbo species (water lilies).

Helminthosporium Disease

Helminthosporium Disease (Bipolris species), (Drechslera species) and (Exserophilum species) are responsible for several leaf spots that occur on all Turf Grass species. Generally they form black or white spots that may be faded and produce masses of spores in the thatch during late summer, under humid conditions. The life cycle is short and when conditions are favourable spores are splashed onto the foliage from the thatch, causing wide spread infection. Cynodon dactylon (common couch) is most susceptible and found in bowling or golf greens where it is a serious problem.

Banana Leaf Spot     

Banana Leaf Spot (Mycosphaerella musicola) is found on many species of banana causing pale yellow streaks on the young leaves to turn brown with dark spots. The leaf then becomes dried, brown and dead commencing from the margins, eventually the leaf dies. Control requires removal of infected foliage or the spraying of a fungicide and fungicides should not be used during the fruiting period.

                  Lophostemon confertus (Brush Box)

Leaf Spot on Brush Box (Elsinoe species). This is a casual fungus that attacks the epidermal layer of the leaf, forming circular spots that are up to 25mm across and are often restricted by the main vein.  These spots are a dull yellowish brown but can also have purplish patterns.  A leaf may have more than one spot develop on its surface and normally appears on scattered leaves throughout the tree.  This doesn't affect the vigour of Lophostemon confertus.

Palm Leaf-scab (Graphiola phoeicis) appears as yellow spots and develop into scabs or warts that are outwards hard and dark but with a soft centre with powdery yellowish brown spores. The infected leaves eventually die.

Palm Leaf Spot, Chamaedorea elegans

Palm Leaf Spot (Pestaloptiopsis species) appears as a small spot with a dark centre on the leaves and affects palms that are growing in shaded humid positions and normally control is not required, though infected fronds should be removed.

Source and Dispersal

Infection source is other contaminated plants and the spores are spread by wind or by splashing water.  The fruiting bodies are black spots that appear on the damaged tissue releasing spores.

Favoured Conditions

This fungus prefers a warm humid environment and leafy plants with soft new growth, particularly if they are crowded.

        

Affected Plants

There are many ornamental and native plants that are hosts to a wide range of fungal leaf spots. Some specific ones are listed below. Plants such as Cornus or Paeonia species are infected by a large variety of leaf spots, while other plants attract a specific leaf spot.

Generally a healthy plant can tolerate fungal leaf spot attack, though it may make the plant look unsightly. In trees and shrubs it is difficult to control and generally not necessary, but in perennials and annuals control may be necessary in order to save the plant.

Acalypha and Arctotis species are infected by up to three leaf spots including (Cercospora acalyphae) and (Ramularia acalyphae) that rarely require control.

Acer species are infected by Purple Eye (Phyllosticta minima) which forms spots with brownish centres and purplish margins causing the death of the leaves.

Acer species are also infected by Tar Spot (Rhytisma acerinum) which forms round black spots that have yellow margins. Not normally seen on cultivated trees, but seen in forests.

Adiantum, Asplenium, Blechnum, Cyathea, Davallia, Nephrolepis, Platycerium, Polypodium and Pteris species are infected by the leaf spot (Pseudocercopora species) which forms circular brown spots on the fronds and heavy infection can defoliate a plant.

Aesculus species are occasionally infected with the leaf spot (Septoria hippocastani) which forms small brown spots.

Agave species are susceptible to the leaf spot (Coniothyrium concentricum), which appear as greyish spots up to 20mm (1in) across with concentric rings and black fruiting bodies. Affected leaves are destroyed as the infection spreads.

Albizia julibrissin is susceptible to the fungal leaf spot (gloeosporium aletridis), which does not normally require control.

Amelanchler, Chaenomeles, Crataegus and Rhaphiolepis species Mespilus germanica are infected by the leaf spot (Fabraea maculata) which may cause considerable damage during wet periods.

Aquilegia species can be infected by three types of Leaf Spot including (Ascochyta aquilegiae), (Cercospora aquilegiae) and (Septoria aquilegiae), normally appearing during humid conditions forming spots on the leaves.

Arbutus species are infected by two leaf spots (Septoria Unedonis) which produces small brown spots on the leaves and (Elsinoe mattirolianum).

Arctostaphylos manzanita is infected by the leave spot (Cryptostictis arbuti) which damages leaves but is not normally detrimental to the shrub.

Aspidistra species are infected by the leaf spot (Colletotrichum omnivorum) causing whitish spots on the leaves and petiole.

Aster species are infected by many leaf spots including (Alternaria species), (Cercosporella cana), ( Ovularia asteris) and (Septoria asteris).

Aucuba species are infected by several leaf spots, usually as a secondary infection after aphid attack. These include (Phyllosticta aucubae) and (Phyllostica aucubae).

                     Azalea

Azalea (Rhododendron species) are susceptible to Leaf Scorch (Septoria azalea). This fungal disease forms reddish- brown spots which expand and engulf the leaf, with fruiting bodies appearing in the centre. Infected leaves die, then fall and the branchlets wilt. This problem is more serious during wet periods and may require control using a fungicide.

Banksia robur

Banksia species are infected by several leaf spots causing chlorotic areas that have brown centres and is not normally a major problem for the plant.

Betula species may be infected by the Leaf Spots (Gloeosporium betularum) that forms brown spots with darker margins and (Cylindrosporium betulae) that also forms brown spots with faded indefinite margins.

Bougainvillea species are infected by the leaf spot (Cercosporidium bougainvilleae) which forms rounded spots with dark margins that yellowish ting. Infected leaves die and fall from the plant.

Calendula species are infected by the Leaf Spot (Cercospora calendulae) which rapidly infects the plant spotting the leaves and killing the plant.

Callicarpa species may be infected by the leaf spot (Atractilina callicarpae) forming irregular brownish spot or (Cercospora callicarpae) which can defoliate the plant in subtropical climates.

Campsis species may be infected by several fungal leaf spots including (Phyllosticta tecomae), (Septoria tecomae) and (Cercospora duplicata).

Carpinus species are infected by the leaf spots (Gloeosporium robergei), (Gnomoniella fimbriata) and (Septoria carpinea), all are minor infections not normally requiring control.

Carya species are infected by several leaf spots including (Gnomonia caryae) that infects leaves with irregular reddish spots on the upper surface with corresponding brown spore producing spots on the underside. It also has a secondary spore release that occurs on the dead leaves where it over winters. Other leaf spots include (monochaetia desmazierii) and (Marssonina juglandis).

Ceanothus species are susceptible to the leaf spot (Cercospora ceanothi) and (Phyllosticta ceanothi) both are of minor importance not requiring control.

Celtis species are infected by many leaf spots including (Cercosporella celtidis), (Cylindrosporium celtidis), (Phleospora celtidis) and (Septogloeum celtidis).

Chrysanthemums species are infected by the leaf spot (Septoria species) which forms yellow spots appear toward the edge of the leaves; these become enlarged brownish patches with yellow margins.  Damaged areas may converge and in severe attacks and the leaves may fall prematurely or flower production is reduced.

Clematis species are infected by the fungal disease (Ascochyta clematidina) which may cause stem rot or leaf spots that are water soaked areas with reddish margins. The infection spreads from the leaves to the stem causing wilting and eventually girdling the stem killing the plant. There are many fungal leaf spots that infect this plant including (Cercospora rubigo) and (Septoria clematidis)

Dracaena deremensis

Cordyline and Dracaena species may be infected by the leaf spot (Phyllosticta maculicola) which forms small brownish spots that have yellowish margins and has black fruiting bodies that forms coils of spores. These plants are also susceptible to other leaf spots such as (Glomerella cincta) and (Phyllosticta dracaaaenae). Keep foliage dry to avoid infection.

Cynodon dactylon,  Pennisetum clandestinum and many other Turf Grasses are susceptible to Helminthosporium Disease.

Daphne species are infected by the leaf spot (Gloeosporium mezerei) and (Marssonina daphnes) both of which form thickish brown spots that are seen on both sides of the leaves. Infected leaves turn yellowish before dieing.

Dendranthema species are infected by many leaf spots such as (Septoria chrysanthemi) which first forms yellowish spots up to 25mm (1in) across that become black. Infected leaves die prematurely and persist on the plant.

Dianthus species may be infected by the leaf spot (Septoria dianthi). It forms light brown rounded spots that have a purplish border. The scattered spots on the lower leaves can also be found on the stems and the spores are dispersed by water from the tiny black fruiting bodies.

Dieffenbachia species are infected by several leaf spot fungi including (Cephalosporium species) and (Myrothecium species).

Eucalyptus species

Eucalyptus species are infected by many fungal leaf spots such as (Mycosphaeralla species), (Hendersonia species) and (Monocheatia monochaeta). Generally leaf spots appear on the juvenile or new leaves causing brownish spots that enlarge and may have a purplish halo around the margin.  Mature adult leaves are not normally infected and the trees rarely require control measures.

Fern species are infected by the leaf spot, (Alternaria polypodii). This fungus appears as brown circular or oblong spots that congregate along the margins of the pinnae causing the fronds to turn brown and die.  It is spread by wind currents from plant to plant and control methods include removing infected fronds and maintaining a drier atmosphere.

Ficus species are infected by various fungal leaf spot including (Pseudocercospora species). Generally the fungal attack forms circular or irregular dark coloured spots on the leaves eventually causing them to fall prematurely.

Ficus elastica is susceptible to many fungal leaf spots including (Alternaria species), (Leptostromella elastica) and (Phyllosticta roberti).

                    Strawberry

Fragaria x ananassa (Strawberry) is infected by the fungal leaf spot (Mycospharella fragariae). The mature leaf is initially infected with well defined brown spots that that turn light grey with red-purplish margins. As the spots merge they form large brown blotches and the leaf turns yellow then dies. This fungal attack normally occurs on plants in poor health and can be a serious problem early in the season seriously damaging stock.

Fraxinus species

Fraxinus species are infected by the leaf spot (Gloeosporium aridum) giving the leaf a scorched appearance as large blotches appear from the margin or apex and turn brown with a papery texture. It is more prevalent during rainy periods and infected leaves fall prematurely. Collect and depose of fallen leaves otherwise control is not normally required.

Fuchsia species may be infected by the leaf spot (Septoria species) or ( Cercospora species), both form spots with dead centres and dark margins.

Gladiolus species are infected by Hard Rot or Leaf Spot (Septoria gladioli). On the corms reddish brown circular water soaked spots become large and sunken. These areas dry out and form obvious margins. The leaves may also have these symptoms but is not commonly seen.

Hemerocallis species are infected by several leaf spots including (Cercospora hemerocallis) and (Heterosporium iridis). These may be in the form of black spots or brownish spots that converge killing the leaf. Infected leaves should be removed and burnt.

Hibiscus species

Hibiscus rosa-sinensis, Hibiscus syriacus and Hibiscus tiliaceus are susceptible to several fungal leaf spots including (Ascochyta abelmoschi), (Cerospora kellermanii) and (Phyllosticta hibiscina). All cause spotting or blotching of the leaf surface; remove and destroy infected parts.

Hydrangea species are infected by four fungal species including (Ascochyta hydrangeae), (Phyllosticta hydrangeae) and (Septoria hydrangeae).

Iris species are infected by several fungal leaf spots including (Alternaria iridicola) and (Macosphaerella species).

Iris species are also infected by the leaf spot (Didymellina macrospore) that forms greyish spots with brown water soaked borders and coalesce on the upper part of the leaf. This casual organism commonly occurs after flowering killing the leaves but will not infect the bulbs. The bulbs become weak over several seasons due to the decreased foliage.

There is also a Bacterial Leaf Spot (Bacterium tardicrescens) that is commonly mistaken as a fungal problem causing translucent spots that coalesce and involve the entire leaf. Normally found on Iris species.

Laburnum anagyroides is infected by the Leaf Spot (Phyllosticta cytisii). The leaf forms light grey spots with no definite margin and mature to brown. The black fruiting bodies appear as dots in the centre of the spot.

Leucanthemum species are infected by the leaf spot (Cerocspora chrysanthemi) and (Septoria leucanthemi).

Magnolia species are susceptible to many species including (Alternaria tenuis), (Mycosphaerella milleri) and (Phyllosticta species). Leaves generally turn brown from the apex or margins turning brown or spots appear on the leaf surface and leaves become yellow before withering and dieing. Normally the make the tree look poorly but have little effect on its growth. Control is not normally required.

Nerium oleander is susceptible to several fungal leaf spots including (Cercospora nerella), (Cercospora repens), (Gloesporium species) and (Phyllosticta nerii). Infected leaves should be removed but generally control is not required.

Nyssa sylvatica is infected by the leaf spot (Mycosphaerella nyssaecola) forming irregular purplish blotches.

Orchids such as Cattleya, Cymbidium, Cypripedium, Dendrobium, Epidendrum, Paphiopedilum, Phalaenopsis and Zygopetalum species are infected by several leaf spots including (Cerospora, Colletotrichum and Phyllosticta species). Normally forming dark or dead, circular or irregular areas on the leaves.

Palms such as Syagrus, Howea, Phoenix, Roystonea and Washingtonia species are infected by Leaf-scab (Graphiola phoeicis).

Palms such as Archontophoenix, Caryota, Chamaedorea, Cocos, Dypsis, Howea, Liculia, Linospadix, Livistona, Phoenix, Ptychosperma, Rhapis, Roystonea, Syagrus, Washingtonia and Wodyetia species are susceptible to several fungal leaf spots including;

(Bipolaris spp.), (Cylindrocladium spp.), (Colletotrichum spp.) and (Pestalotiopsis spp.).

Generally the circular leaf spots are brown and may have a yellow halo such as Palm Ring Spot (Bipolaris incurvata). They vary in size from small to large depending on the species. When a plant is healthy it recovers from attack, but heavy infections can defoliate, causing the collapse of the plant.

Palms are also infected by the Brachybasidium Leaf Spot (Brachybasidium pinangae). This fungus forms angular leaf lesions that produce fruiting bodies on the underside and is commonly found on Archontophoenix species.

                  Archontophoenix cunninghamiana

Passiflora species are infected with many types of leaf spot such as (Alternaria passiflorae).

Phoenix species are susceptible to False Smut (Graphiola phoenicis). This fungus forms yellow leaf spots that become hard with a raised with a blackish scab, which produces masses of powdery spores that are thread-like.

                  Pittosporum species

Pittosporum species are susceptible to the leaf spots (Alternaria tenuissima), (Phyllostica species) and (Cercospora pittospori). Circular or angular dark spots appear on the leaves and are surrounded by necrotic areas that are yellowish. Generally removal of infected leaves is adequate control.

Poa species and other cool season grasses are infected by Winter Fusarium Leaf Disease (Fusarium species), which causes small pale spots that are water soaked to appear on the leaves that turn red-brown. Infected leaves become bleached then wither and die, but the infection will not affect the crown or roots of the plant. It can be identified by pink, cotton-like mycelium and the plant prefers cold wet weather.

Populus species are infected by several fungal leaf spots including (Ciborinia bifrons, Ciborinia confundens), and (Mycosphaerella populicola).

Prunus species are infected by several leaf spots including (Cercospora circumscissa and Septoria ravenelii).

Pseudotsuga menziesii Douglas Fir is infected by the Leaf Cast (Rhabdocline pseudotsugae) Symptoms include the needles becoming yellowish at the apex and extending down the needle and spreading to others during moist spring weather turning them brown. Brownish scorched areas are noticeable on the tree from a distance. Control; is not normally required for mature trees but nursery stock may require spraying with a copper based fungicide.  

Psidium guajava (Guava) is infected by (Glomerella cingulate). This fungus courses spots to appear on leaves and mummifies and blackens immature fruit or rots mature fruit.  This fungus can devastate a guava crop.  

Quercus species are infected by several types of leaf spot including (Cylindrosporium microspilum) and (Marssonina martini). These attacks tend top take place later in the season and normally not detrimental to the tree.

Rhododendron species are infected by a large variety of fungal leaf spots including (Cercospora rhododendri) and (lophodermium melaleucum)

Salix species are infected by several fungal leaf spots including (Ascochyta salicis) and (Septogloeum salicinum).

Senecio species are infected by the fungal leaf spot (Alternaria cinerariae) and (Cercospora species), forming dark rounded or angular spots.

Spiraea species are attacked by the fungal leaf spot (Cylindrosporium filipendulae).

Stenotaphrum secundatum (Buffalo) turf grass is susceptible to Grey Leaf Spot (Pyricularia grisea) in domestic and commercial situations devastating lawns. This fungal disease infects the stems and leaves with small brown lesions that enlarge rapidly forming grey-brown spots that have darker borders or surrounded by yellow chlorotic areas. This infection is commonly found on newly laid turf but will also infect established lawns. It is most prevalent during warm humid periods in soil with a high nitrogen level.

Syringa species are attacked by up to six species of leaf spot including (Cercospora lilacis) and (Phyllostica species).

Syzygium species

Syzygium species are infected by fungal leaf spots but normally control is not required.

Tagetes species are infected by the leaf spot (Septoria tageticola), which starts at the base and moves progressively up through the plant, covering the leaves in grey to black spots.

Trillium species are host to several leaf spots, including (Colletotrichum peckii) (Gloeosporium Trillii) (Heterosporium trillii).

Ulmus species are infected by many fungal leaf spots including (Gnomonia ulmea) and (Cercospora sphaeriaeformis).

Veronica species are infected by the leaf spot (Septoria veronicae). The symptoms include small violet to brown spots appear on the upper surface of the leaf and correspondingly yellowish brown on the underside. The spots converge forming a scorched shot-hole appearance and eventually death of the leaf.

Vaccinium ovatum

Vaccinium ovatum is infected by the leaf spot (Rhytisma vaccinii) and (Dothichiza caroliniana).

Vicia species are infected by the leaf spot (Erostrotheca multiformis), which forms greyish spots that enlarge and may defoliate the plant.

Wisteria species are infected by three fungal leaf spots (Phyllostica wisteriae), (Septoria wisteriae) and (Phomatospora wisteriae).

Non-chemical Control

Remove and destroy infected plant material and avoid overhead watering.  When planting select infection resistant varieties. Practice crop rotation and add pot ash to the soil to decrease the plants venerability to the disease. Many species of fungus overwinter in fallen leaves, remove and destroy any litter under the plant.  

Winter Fusarium Leaf Disease in Turf Grasses can be minimised by aerating the soil, reducing thatch and avoid excessive nitrogen in the soil.

Chemical Control

Protective fungicides such as zineb or copper oxychloride should be sprayed at the first sign of infection and cuttings should be sprayed as they start to grow.

Note

Always read the label for registration details and direction of use prior to application of any chemicals.

DISEASE

   NAME

     Damping-off

     Various Damping-off Species

Description

A soil based fungal problem that involves three types.  Pythium species, Phytophthora species and Rhizoctonia species, which is the main cause of wire-stem and produce brown fungal threads if a part of the leaf touches the soil.

The Pythium ultimum is also responsible for root rot of succulent or tropical plants.

Symptoms

The fungal attack can occur below (pre-emergence) before the seedling appears or above soil level (post-emergence) as the seedling develops cotyledons. The rot occurs on the roots and can move into the stem making the seedling to topple or the fungus attacks the outer layer of the stem only leaving a thin cord to support the plant (wire-stem). It may also produce fine threads that spread from the top of the seedling to other seedlings. In succulent nursery stock the fungus rots the roots causing the death of the plant.

Source and Dispersal

These funguses are found in soil and Pythium species can be transmitted in water, as in irrigation. Insects, animals and contaminates soils or containers are also responsible for dispersal.

Favoured Conditions

It prefers wet soils and a warm humid environment as in a propagation glasshouse.

Affected Plants

It affects all seeds and seedlings and Aloe or Haworthia species, nursery stock.

Aloe species especially in a nursery situation are venerable to the Root Rot (Pythium ultimum).

Begonia and Delphinium species are infected by (Pythium debaryanum) and (Pellicularia filamentosa). These fungi attack seedlings or cuttings causing death.

Rhododendron and Callistephus species are infected by the fungus (Pellicularia filamentosa) particularly when over watered causing stem rot in older plants and infects seedlings.

Robinia species seedlings are infected with (Phytophthora parasitica) normally in a nursery situation.

Brown Patch Agrostis palustris     

Turf Grass such as Agrostis palustris (Bent), Festuca arundinacea (Fescue) and Cynodon species (Couch) are infected by Brown Patch (Rhizoctonia solani). This fungus forms brown discoloured areas that turn white-grey up to 50cm across with a brown smoky coloured border. It is found in particularly heavy thatched turf in warm humid conditions. Excessive nitrogen and poorly drained soils favour infection and can be seen in the early morning when the dew is on the turf. It is active from spring to summer and may be associated with other fungal attacks.

Turf Grass is also infected by Damping Off (Pythium species) affecting many cool season species and several warm season species. Yellow patches appear, with the seedlings of new lawns becoming stunted and the seedlings are covered in water soaked lesions, which kills them. Mature lawns can also be infected.

Pythium species also cause Root and Crown Rot in cool or warm season turf that is in wet soils or have excessive thatching. Improved drainage and minimal thatch will reduce infection.

Non-chemical Control

Avoid overhead watering of seedlings, and allow the soil to drain before rewatering. Avoid wet boggy soils and sow the seedlings thinly avoiding over crowding. Improve air circulation and infested seedlings with there soil should be discarded.

Heat treat the growing media before use and disinfect containers.

Chemical Control

There is a range of systemic fungicides suitable for controlling this problem. Furalaxyl will control Pythium and  Phytophthora species and Quintozene may be used to control Rhizoctonia species.

Note

Always read the label for registration details and direction of use prior to application of any chemicals.

DISEASE

   NAME

     Root Knot & Other Nematodes

     Meloidogyne & other species

Description

Root Knot Nematode or eelworms are transparent thin nematodes that are an organism up to 0.5mm long and attacks the roots by injecting saliva that stimulates the surrounding cells to form galls. The adult male lives in the soil and the female are found in the roots, laying up to 2,000 eggs in a mass in the soil adjoining the roots.

                 

Symptoms

Above ground the plant infected by Root Knot Nematode develops slowly and is stunted. During hot weather the plant wilts easily as it is unable to keep up with the transpiration rate and under extreme conditions the plant dies. The young nematodes attack the roots forcing there way up the root tips forming galls. On inspection the galls are found centrally located along the roots and are up to 20mm across. The galls slow the rate of nutrients and water passing through the plant and as the galls break down they allow opportunity for other diseases to enter the plant.

The roots are severely damaged if the galls are physically removed.

Other species of nematode have simular symptoms and are individually discussed below.

Source and Dispersal

The nematodes are found in soil or in infested plants and are dispersed by water, soil movement and attached to tools or shoes.

Nema Head

Favoured Conditions

It prefers sandy soil types and a warm moist weather conditions.

Life Cycle

Affected Plants

A wide range of plants are attacked by the Root Knot Nematode  including tomatoes, potatoes, carrots, tobacco, hibiscus, gardenia and roses. Some species of nematodes are plant specific such as (Meliodogyne incognita) which attacks Hemerocallis, Celosia and Viola species, forming small wart-like swelling on the roots.

Alternanthera, Begonia, Dianthus, Psidium, Thunbergia and Weigela species are attacked by the Root Nematode (Meloidogyne incognita). This forms small swellings on the roots causing the top growth to be stunted and not responding to improved culture. In cool climates it is found on plants in glasshouses.

Buxus species are attacked by the Meadow Nematode (Pratylenchus species) that turn the leaves a bronze colour and cause stunting of the plant. These microscopic nematodes enters through the roots and eventually result in the death of the plant.

Lagunaria patersonii is attacked by a simular nematode, the Root Burrowing Nematode (Radopholus similis) that feeds by burrowing in the outer root tissue.

Lavandula species that are grown in the northern United States are susceptible to the Peanut Root Knot Nematode (Melioidogyne hapla).  Berberis species are also susceptible.

Tulipa species are attacked by Bulb and Stem Nematode (Ditylenchus dipsaci) which forms brownish streaks along the stem that may blister and may cause wilting. The flowers petals become distorted and the general vigour of the plant poor.

                  Nematodes damage

Turf Grass are susceptible to several Parasitic Nematodes including (Helicotylenchus species), (Xiphenema Species), (Hemicycliophora species) and (Ibipora lolii). All turf grasses are susceptible and the nematodes are active from spring to autumn requiring a soil temperature 15 ºc. The leaves become chlorotic and have a weak appearance as a result of the damaged roots. Generally it is only a major problem when the nematode numbers are very high, otherwise control is not warranted.  

Cultural Control

Crop rotation in infected soils, avoid using plants from the Brassicaceae family for up to four years and plant species that are tolerant of nematodes, this will reduce numbers. Beds may be laid fallow for several seasons to deter nematodes, but numbers build up quickly once susceptible plants return.

Affected plants such as roses may have the bare roots dipped in hot water 45ºC for 15 minutes during the dormant period and contaminated growing media can be heat treated at 60ºC for 30 minutes before being used.

Any infested plants should be removed and destroyed or deposed off site.

Improve the soil structure and avoid acidity by the addition of lime or dolomite. Garden beds may also be pre planted with marigolds or mustard to deter nematodes, but should be removed or thoroughly composted prior to planting as they can push nematodes towards the crop. Green manure crops may be grown prior to planting and infested soil may require up to three seasons of manure crops to bring nematodes under control.

Biological Control

The encouragement of earthworms reduces nematode numbers as they accidentally eat them in there normal course of growth.

Chemical Control

The soil can be treated with a nematicide such as fenamiphos in a domestic situation. Commercial growers may fumigate the soil prior to planting with the appropriate chemicals.

Note

Always read the label for registration details and direction of use prior to application of any chemicals.

DISEASE

   NAME

     Powdery Mildew

     Various Powdery Mildew Species

Description

Powdery mildew covers arrange of fungal infections most with simular characteristics of white powdery areas appearing on the leaves and flowers.

     White powdery area     

Symptoms

Powdery mildew (Oidium species) affects the following five plant groups with slightly different characteristics.

Cucurbits firstly form white spots on the underside of the leaves. Under optimum conditions the fungus spreads to the upper surface covering the entire leaf causing it to die. It may also extend to the stems slowing the growth of the plant and may reduce the size of the fruit.

Grape leaves, flowers and fruit are attacked with the appearance of greyish-white powdery spots. Infected flowers set poor quality fruit and infected fruit splits open and dries out.

Pawpaw leaves become infected on the underside at first then spreading covering the entire leaf. The fruit forms irregular light grey spotted areas that damages the surface and under the surface causing the fruit to misshapen and reducing its market value.

Rose leaf and buds are covered in a fine white powdery coating and in severe cases it extends to the stems. When young leaves are infected they become distorted and older leaves develop blackened areas. Infected flower buds may fail to open and opened blooms may be discoloured or distorted.

Strawberries show different signs of infection with the leaf margins first rolling upwards then developing purplish irregular blotches along the veins.  The infected flowers may fail to set fruit and if fruit is produced it is small, hard fails to ripen. Semi mature fruit that is infected has dull appearance and may form cracks or split open.

The Powdery Mildew (Sphaerotheca lanestris) infects leaves and twigs. The under side if the leaf firstly has a white mealy growth that matures to felt-like brown mycelium that can cover the entire leaf, and the twig tips. It is only one of the many types that infect Quercus species.

Source and Dispersal

The spores overwinter in fallen leaves, dormant buds, seed and infested plants. It is dispersed by wind.

Favoured Conditions

Generally it prefers warm humid conditions, but failing to germinate when it is raining. The fungus that attacks Pawpaw prefers cooler conditions disappearing in the warmer months.        

Affected Plants

There are many plant species ornamental trees and shrubs that are attacked by Oidium species including; Roses, African Violets, Cucurbits, Grapes, Pawpaw, Strawberries, Hydrangeas, Ajugas, Antirrhinum, Oaks and Photinias.

Acer species are infected by the powdery mildews (Uncinula circinata) and (Phyllactinia corylea) but are not normally serious.

Aesculus species are infected by the powdery mildew (Uncinula flexuosa) which forms a white mold on the underside of the leaves.

Arenaria,Cuphea, Erica and Eschscholtzia species are infected by the powdery mildew (Erysiphe polygoni). This fungus is greyish or white and covers leaves or young shoots. Heavenly infected leaves turn brown and fall from the plant. The plant eventually dies.

Aster species are infected with the powdery mildew (Erysiphe cichoracearum) which is more prevalent on the lower part of the plant.

Ceanothus, Corylus, Platanus, Syringa and Weigela species are infected by the powdery mildew (Microsphaera alni) particularly London Plane. The mycelium forms a felt-like cover on the leaves.

Celtis species are susceptible to the powdery mildew (Uncinula parvula) and (Uncinula polychaete). This fungal problem can affect either side of the leaf, which can have spots or be completely coved in mildew. The fruiting bodies appear on the opposite side of the mildew.

Cornus species leaves are infected by the powdery mildew (Microsphaera alni) and (Phyllactinia corylea), covering the leaves in a whitish fungus.

Dahlia species are infected by the powdery mildew (Erysiphe cichoracearum) that forms white powdery areas on the leaf surface.

Lagerstroemia species are infected by the powdery mildew (Uncinula Australiana) that forms white powdery growth on the leaves and may also distort the infected foliage.

Populus and Salix species are infected by a white powdery mildew (Uncinula salicis) that produces black fruiting bodies with a curled tip, but is not normally a major problem.

                  Quercus robur

Quercus species are susceptible to several powdery mildew fungi including (Sphaerotheca lanestris), (Erysiph trina) and (Phyllactinia corylea). Generally white mealy growth appears on the leaves, normally on the underside turning the infected areas brown and then the leaf dies. The infection may spread to the twig tips causing dieback. Control may be difficult and unwarranted on large trees but nursery stock may be sprayed with a fungicide during susceptible periods.  

Rosa species are also infected by the powdery mildew (Sphaerotheca pannosa).

Rudbeckia and Senecio species are covered in white fungus (Erysiphe cichoracearum) which infects leaves, flowers and stems. This results in the plant becoming stunted.

Senecio species are infected by the powdery mildew (Sphaerotheca fuliginea) which forms circular white powdery areas on the leaves.

Spiraea species are infected by the Powdery Mildew (Microsphaera alni) and (Podosphaera oxyacanthae).

Ulmus and Rhododendron (Azalea) species are also infected by (Microsphaera alni). Circular patches of white powdery growth appear on the leaves.

Veronica species are sometimes infected by the powdery mildew (Sphaerotheca humili) causing a white coating to appear on the leaves. Not normally a major problem.

                 

Zinnia elegans are commonly infected by the powdery mildew (Erysiphe cichororacearum), which appears on both sides of the leaves as a greyish powdery cover and may be transmitted by seed.

Non-chemical Control

Choose less susceptible species and when planting space the plants to allow good air circulation. Avoid overwatering and try to keep the foliage dry. Affected plants may be dusted with powdered sulphur or sprayed with a milk mixture to discourage mildew. Vegetables that are infected with mildew should be removed and replaced with new young plants, as they are more resistant to infection.

Chemical Control

Prenatitive spraying during warm humid conditions using a suitable fungicide such as wettable sulphur, bitertanol, carbendazim, fenarimol and triforine helps control the problem.

Note

Always read the label for registration details and direction of use prior to application of any chemicals.