Clematis montana

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.

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

     Aphids

     Various Aphid Species

   ORDER

     Hemiptera

   FAMILY

     Aphididae

Description of the Pest

The common name varies and aphids may be referred to as black fly, greenfly, ant cows or plant lice.

These small insects have soft globular body that is from 1mm to 8mm long and vary in colour from green, yellow, black and pink, with the winged forms being elongated. Both adult and nymphs, have piercing and sucking mouthparts.

Aphids are found on buds, flowers, or leaves and stems, preferring soft new growth. On older leaves the aphids are found in protected positions, such as under the leaf. Certain species of aphids form galls as they suck sap and may be found on the roots of the plant. (E.g. Woolly aphids and Black peach aphids)

Most aphids possess a pair of characteristic tubular projections, known as cornicles; these secrete a pheromone and a waxy fluid, which is thought to protect them from some of their predacious enemies.

White exoskeletons, honey dew and sooty mould indicate the presence of Aphids

Balsam Twig Aphid (Mindarus abietinus) is greenish and covered in a white wax and is normally found on the young shoots of conifers bending and killing the needles. It is found on Abies and Picea species.

Aphid and their exoskeletons    on underside of a leaf

Black Citrus Aphid (Toxoptera aurantii) has a soft plump green body and the black coloured adults may or may not be winged. They feed in groups, curling leaves and producing honeydew attracting sooty mould.

Green Peach Aphid (Myzus persicae) is a soft plump green insect up to 0.2mm long and may be wingless. The nymphs are yellowish green and are responsible for spreading viruses in Dianthus species.

Spruce Gall Aphid (Chermes abietis) form cone shaped galls up to 12mm long resulting from the feeding. The wingless female adult lays eggs on the stems and the immature females overwinter on bud scales. Large infestation will weaken trees such as Picea abies and Pseudotsuga menziesii.

Tulip Bulb Aphid (Anuraphis tulipae) is small, waxy grey coloured and infests the underside of the bulb scales or rhizomes. They occur in the ground or on above ground parts and during storage.

Life Cycle

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

During spring all eggs produced hatch as female nymphs. Adult Aphids are capable reproducing without fertilisation.  The males are only produced in some species as the weather cools down, and the day length shortens.

Aphids are capable of giving birth to living young and large populations build up quickly during summer. Over crowding causes the aphids to become smaller, less fertile and produce more winged forms that can migrate to other host plants.

There are many different types of aphids and the life cycle varies from warm to cold climates.

Typical life cycles

Distribution of the Pest

World wide

Period of Activity

In warm climates they are seen throughout the year, but aphids dislike hot dry or cold conditions and heavy rain will decrease the population. In cold areas aphid eggs are laid around a bud base or other protected areas of the plant during autumn and emerge as nymphs during spring, feeding on the new growth.

Numbers build up quickly in the warmer months of the year. Some species feed during winter on Sow thistles.

Susceptible Plants

There is a wide range of plants attacked, from roses to vegetables, shrubs and trees. Certain aphids attack a specific genus while others have a wide range of host plants. Many are capable of transmitting plant virus diseases.

Adults and nymphs feeding    A colony of aphids

Acer species are attacked by several aphids including the Norway Maple Aphid (Periphyllus lyropictus) which is a greenish with brown markings and secret honeydew, preferring Acer platanoides. Other aphids include (Drepanaphis acerifolia) and (Periphyllus aceris) which are commonly found on the underside of leaves.

Acer species are also attacked by the Woolly Maple Aphid (Phenacoccus acericola) which covers the undersides of the leaves with a cotton-like mass

Alnus species are infested with the Alder Blight Aphid (Prociphilus tessellates) which is blue-black adult that forms woolly masses on the down-turned leaves. The nymphs overwinter in bark crevices.

Aquilegia species are attacked by several aphids including (Pergandeidia trirhoda) which is a small, flat cream coloured insect that is found on young branches and the underside of leaves.

Betula species may be attacked by the European Birch Aphid (Euceraphis betulae) which is small and yellowish or the Common Birch Aphid (Calaphis betulaecolens) which is large and green producing ample honeydew for sooty mold to grow on.

Callistephus species may be attacked by the Corn Root Aphid (Anuraphis maidi-radicis) causing the plant to become stunted, the leaves wilt and turn yellow. The aphids feed on the roots producing honeydew and are dispersed to other host by ants. It is also attacked by the Potato Aphid (Macrosiphum solanifolii).

Carya species are attacked by Gall Aphids (Phylloxera caryaecaulis) which is found on the leaves, twigs and stems forming galls and turning them black.

Chaenomeles and Gladiolus species, new growth and leaves become infested with the aphid (Aphis Gossypii)

Cupressus macrocarpa may become infested with the Cypress Aphid (Siphonartrophia cupressi).

Cyclamen species are attacked by the aphid (Myzus circumflexus) and (Aphis gossypii) which can infest healthy plants.

Dendranthema, Dianthus  and Crocus species are attacked by several types of aphid including the Green Peach Aphid (Myzus persicae) and the Chrysanthemum Aphid (Macrosiphoniella sanborni).

Hibiscus species are attacked by the aphids (Aphis craccivora)  and (Aphis gossypii), both congregate towards the branch tips and may cause leaf curl. Normally only seen in sub-tropical climates.

Aphids on a stem    Mandevilla species

Larix species is attacked by the Woolly Larch Aphid (Adelges strobilobius). The winged adults deposit eggs at the base of the needles during spring and white woolly areas appear attached to the needles where the adult aphids feed. The young aphids overwinter in the crevices of the bark.

Mandevilla species is attacked by aphids that congregate towards the branch tips and may cause leaf curl.

Pinus species is attacked by several species of aphid including Pine Bark Aphid (Pineus strobi), Pine leaf Aphid (Pineus pinifoliae) and the White Pine Aphid (Cinara strobi).

Primula species are attacked by four species of aphid including foxglove, and green peach aphid.

Rudbeckia, Delphinium, Chrysanthemum and Helianthus species are attacked by a bright red aphid (Macrosiphum rudbeckiae).

Sorbus aucuparia is affected by the Rosy Apple and Woolly Apple aphid which attacked the foliage and young shoots.

Spiraea species are attacked by the Aphid (Aphis spiraecola) which feeds on the young shoots and flowers.

Tropaeolum species are attacked by the Black Bean Aphid (Aphis fabae), which is found in large numbers on the underside of the leaves, turning them yellow and causing them to wilt then die.

Tulipa, Iris, Freesia, Gladiolus and Zephyranthes species are infested with the Tulip Bulb Aphid.

Ulmus species are infected by two types the Woolly Apple Aphid (Eriosoma lanigerum), which curls and kills young terminal leaves and the Elm Leaf-Curl Aphid (Eriosoma ulmi) which occasionally attacks the trees.

Viburnum species are attacked by the Snowball Aphid (Anuraphis viburnicola). This aphid congregates at the end of the branches causing the leaves to curl and become deformed under which they hide.

Aphids on Quercus robur

Damage Caused

Buds that have been attacked may not open, leaves and twigs become twisted or distorted and wilt. The aphids also produce honeydew, which is sticky and attracts sooty mould (fungus). This fungus forms a thick layer over the leaf, fruit or stems reducing the plants photosynthesis capability. The sooty mould spoils the plants appearance and its fruit, as does the insects white exoskeletons.

Control

Cultural Control

Aphids may be removed from a plant by hosing them off with water (limited success) or applying soapy water to aphids.. Another organic sprays can be efficient in controlling aphids. Aphids  may also be removed physically by hand for small colonies on spine less plants. Species that live under ground are difficult to control but cultivation of the surrounding soil may help in controlling the infestation. (limited mainly to annual or commercial crops)

Reflective mulch around the plants also reduces numbers by repelling the insect this material is available commercially. (Reflective mulches are mainly used in market gardens for avoiding the Green peach Aphids) Resistant rootstocks are available to avoid some root feeding aphid of commercial plants, e.g. Vines and fruit trees

Biological control

Aphids are attacked by several insects includes parasitic wasps or predators such as ladybirds/ lady beetles, hover flies, lacewings, spiders.

   Parasitised aphids

Chemical Control

Aphids may be controlled by spraying with a contact or systemic insecticide. The type of application used will depend on the plant is being attacked.

Aphids can be suffocated and therefore controlled with the use of e.g. White oil, Pest oil, Soapy water from soap such as Lux Flakes ®

Note

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

Monitoring

Aphid are attracted by yellow colour and traps such as boards painted yellow and covered in glue or sticky substance will attract and trap the insects.  There is also a commercially sticky yellow tape that can be attached to susceptible plants

Amendments by B. Sonsie Dip Hort Sc Burnley

PEST

   NAME

     Cutworms

     Agrotis species

   ORDER

     Lepidoptera

   FAMILY

     Noctuidae

Description of the Pest

Cut worm larvae live in the soil, congregating in weedy areas; they chew off young seedlings at the base. They are smooth, thick fleshy grubs that vary in colour, from pinkish brown to olive green, or almost black. They grow up to 40mm long and 5mm thick. Larvae curl up when disturbed, pretending to be dead. Larvae burrow down into the soil to a depth of about 50mm to pupate. Adults are dark brown, hairy moths, with a wingspan of about 60mm.

These insects have a Holometabolous life cycle, ie. When metamorphosis is observed during the pupal stage.

    

Appearance of the Pest

Adult moths are strong fliers capable of flying many kilometres laying eggs over a wide area. The eggs may remain dormant for several weeks until it rains or emerge within a few days under the right weather conditions.

Three similar species are commonly found in Australia:

·        Agrotis ifusa (Bogong moth) is up to 50mm across and has three spots on its forewing.

·        Agrotis munda (pink cut worm); and

·        Agrotis ipsilon (black cut worm).

Agrotis munda

Period of Activity

Different species are active throughout the year, their prevalence being determined by rainfall and temperature. They are normally most active at night. Larvae will appear in greatest numbers when favourable environmental conditions produce lush growth.

Susceptible Plants

Cutworms prefer soft, succulent seedlings or fleshy annuals, perennials and a variety for ferns or orchids. They feed at night and remain in the soil during the day.  They are most commonly found in soil that is infested with weeds or soil that is poorly drained and moist. Well-drained soils harbour less lava.

Senecio and Dianthus species are attacked by the Cutworm (Peridroma margaritosa) which eats seedlings, leaves and flower buds. Under glasshouse conditions all stages of the lifecycle are present.

Turf Grasses are attacked by several Agrotis species causing damage during different seasons according to there individual life cycle. All feed at night on the leaves when young and mature larvae shear plants stems at ground level.

Damage Caused

Young larvae feed on the lower epidermis of leaves. Adults attack stems and seedlings at the base, eating the soft new growth, on one side, or completely through. The damaged plant normally topples over (hence the common name). Mature plants may wilt or the foliage becomes yellowish as a result of the damage, but normally recovers.

Cultural Control

Weed removal and cultivation to improve the drainage of the soil will provide some reduction in of numbers. Seedlings may be protected by a physical barrier, (eg plastic tube pushed into the soil around the seedling).  Heavily infected soil can be laid fallow with for several weeks to disrupt the life cycle or the soil can be covered in black or clear plastic until weeds and lava are dead.

A molasses based bait that has hardwood sawdust and bran mixed with water creates a stick mass that the lava is attracted to but cannot escape. At sunrise they die from dehydration.

Biological Control

Natural predators such as birds, ground beetles and certain bugs help keep numbers down. Wasps and certain species of flies also attack the lava.

Encouraging earthworms by mulching and increasing the humus level is an excellent way to rid the soil of lava.

Chemical Control

Chemical treatment (Carbaryl) may be effective if sprayed in the evening, when the caterpillars emerge to feed.

Note

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

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

     Earwigs

     Various Earwigs Species

   ORDER

     Dermaptera

Description of the Pest

Earwigs are slender insect with large pair of curved forceps at the rear of the abdomen and may be black to brownish. All Earwigs lay eggs in groups of 50 in the soil up to 50mm deep and tend the new borne for up to two weeks.

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

European Earwig (Forficula auricularia), the male has curved forceps and the female has straight forceps. The folded wings cover the thorax and the insect is reddish brown, up to 20mm long. When disturbed it omits a fluid from its back, but will not harm humans.

                 

Appearance and Distribution of the Pest

Earwigs are normally found in dark, damp places such as under rocks, logs, stones and in decaying organic material as found in weedy places. They emerge from the soil or from inside the petals at night to feed on the host plant and are dispersed by flying or walking to new areas. They may also be transported in soil or on vegetative material to new regions.

Period of Activity

They are most active during the warmer months from summer to autumn. The females deposit eggs during spring and summer, which generally produces one generation per year. Eggs are laid in the soil and the female guards them until they hatch. The nymphs have six stages and the adults tend to be nocturnal.

Damage Caused

The European Earwig is a serious pest and eats holes in flower buds, fruit or leaves causing no distortion in the growth but the margins are left ragged. In a glasshouse or bush-house the insect feeds on the root tips of epiphytic orchids, fern tips or new shoots. The Australian native species cause little harm.

Susceptible Plants

A wide range of plants are attacked these include vegetables, ornamental perennials such as Chrysanthemum species and dahlias.

Cultural Control

Insects may be trapped in shredded newspaper or between slightly spaced grooved  timber and in upturned pots with straw in side. They may be collected by hand and drowned in soapy water. Remove any dead plant material from around the base of the plant.

Chemical Control

Infested areas can be dusted with lime or naphthalene flakes. The plants may also be sprayed with Carbaryl in heavy infestations.

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 the Rabbit Resistant plants not the susceptible plants.

 

PEST

   NAME

     Rabbits

     Oryctolagus cuniculus & Sylvilagus species

   ORDER

     Lagomorpha

   FAMILY

     Leporidae

Description of the Pest

There are a eight different genera in the family classified as rabbits and include the European Rabbit (Oryctolagus cuniculus) which has infested Australia and the Cottontail rabbit  (Sylvilagus spp.) which consists of 13-species with 9-species found in North America.

Generally rabbits have an egg-shaped body that can range in size from 200 mm to 500 mm long and weigh up to 2 kg.  They have long ears that are adapted for detecting predators and powerful large hind legs allowing them to move fast.  The body is covered in buffed, long soft fur that is brown or grey and the mouth has two sets of incisor teeth which are located one behind the other.

The cottontail rabbit grows up to 450 mm (18 in) tall and weighs 1.36 kg (3 lbs).

Appearance and Distribution of the Pest

Generally rabbits live in a variety of habitats including meadows, woodlands, forests, grasslands or deserts and wetlands living in groups with some underground in borrowers.  The European Rabbit has been introduced to many parts of the world and in 1859 Thomas Austin brought 24 breeding pairs to Australia which subsequently escaped and quickly bred throughout Victoria and New South Wales and  by the 1900's the rabbits had reached the Northern Territory and Western Australia.

Life Cycle

The life span varies with each species. Cottontails for example can live for one year to a maximum of three years in the wild but in captivity they can last for eight years, during which time they can raise between 2-6 litters per year and produce up to 18 kittens during the breeding season. In the cooler northern parts of North America the size and number of litters are generally smaller only 2-3  but in southern regions such as Mexico or Australia, European rabbits can produce 5-6 litters per year, normally commencing during spring time and continuing throughout the year. Each litter can consist of 2-8 or more kittens. Under ideal seasonal conditions a mature doe (female) can mate again several hours after giving birth and has a gestation period from 28-30 days.  

Period of Activity

Generally rabbits eat throughout the year but in cooler countries such as North America they are more active during the spring to summer period but in warmer climates such as Australia rabbits can cause significant damage throughout the year.

Damage Caused

in Australia the effects of rabbits on the landscape has been a devastating resulting in the loss of an unknown number of plant species and a ring barking of young trees in orchards or forests.  Major erosion problems have also resulted from warrens or plant denuded landscapes which are left vulnerable to the elements.

A rabbits generally will eat most flowers or the bark of woody plants, grasses of all types and most agricultural crops (vegetables).

Susceptible Plants

Rabbits mainly consumed grasses or garden vegetables and a broad range of ornamental plants.  In cool climates where snowfalls rabbits eat twigs, bark and buds from the dormant plants. When rabbits are hungry they will eat most plants but attached to this file are rabbit resistant plants that are less palatable. Their resistance will vary depending on the stage of growth as new shoots are very desirable to rabbits.

Cultural Control

Control methods include trapping, hunting and exclusion with the use of fences, all of which had a marginal success. Many predators utilise rabbits as a food source for example foxes, feral dogs and cats, hawks or owls and human hunters.

Biological Control

In Australia to biological diseases have had reasonable success. In 1950 Myxomatosis was released into the rabbit population and resulted in the numbers dropping from 600 million to 100 million. Remaining populations became immune and steadily increased numbers to 300 million by the 1990s.  The calicivirus was accidentally released in 1996 and culled populations significantly in regions of extreme heat but was less effective in cooler regions where the rabbits were exposed to a lesser calicivirus that immune them.

Chemical Control

Baiting and chemical repellents programs relied on the territorial habits of rabbits as they rarely forage further afield from their territorial areas.

Note

Landholders should seek advice from their local government agencies.  This advice will include fumigation or destruction of warrens, fencing and shooting.

DISEASE

   NAME

     Verticillium Wilt

     Verticillium dahliae

Description

This is a soil based fungus that attacks the root hairs and travels throughout the plants vascular system.

Symptoms

With annuals or perennials such as dahlias lower leaves wilt, turn brown and die and the stems appear normal until the base splits open and turns blackish. This may extend throughout, killing the plant. With larger trees the fungus causes the leaves at the end of the branches wilt and die off.

Verticillium albo-atrum is a soil born fungus that normally infects the roots acting on the water conducting cells by restricting flow causing the plant to wilt. On trees the leaves suddenly wilt and die. This may happen on individual branches on one side of the tree. Other symptoms are leaves form smaller than usual turning yellow and the plant may not shoot the following season. Trees may die over a short or long period of time depending on the severity or number of infections it has incurred and Acer saccharinum and Catalpa species are most susceptible.

Source and Dispersal

It is found in the soil and dispersed by movement of soil i.e. in containers or on machinery. The fungus may survive in the soil for many years.

Favoured Conditions

Moist poorly drained soils are prone to fungus and during the cooler humid months the fungus is most active.        

Affected Plants

There is a wide range of hosts including tomatoes, potatoes, chrysanthemums and other perennials. It also found in shrubs and trees.

Acer, Achillea, Koelreuteria , Paeonia  and Syringa species are infected by Verticillium albo-atrum causing wilting. Erythrina x sykesii may also become infected.

Berberis species are infected with Verticillium albo-atrum causing the leaves to turn brown, shrivel then die.

Non-chemical Control

Cultivate soil to improve drainage and aeration. Cut down and destroy any infected plant material and when taking cuttings from a susceptible plants quarantine them, to ensure they are not infected. Infected soil may be allowed to lay fallow for 2 to 3 years and when replanting used resistant plant varieties.

Chemical Control

For quick control of a cultivated area the soil will require treatment with a fungicide. Consultation with your local Department of Agriculture is advised.

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

     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

     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.