1. Pests of Orchards California red scale Grape vine moth
Citrus leaf miner
White louse scale
Queensland fruit fly
Phylloxera
Anthracnose
Lemon scab
Melanose
Spined citrus bug
Other problems
deficiencies
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2. California red scale Order- Hemiptera ( hard)
Appearance – The adult female cover circular, conical orange/red. The winged adult male cover is oval & grey. Crawlers & adults inject a toxic poison in saliva
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3. California red scale California red scale crawlers
Adult male California red scale.
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4. California red scale
Damage- All of the above ground may be infested= Fruit blemishing, leaf yellowing, fall, twig & branch die back
Halo effect on leaf
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5. California red scale
Plants affected- Citrus,Acacias,Willows, Olives. Most widespread pest of citrus in NSW.
Conditions- Prefers dry inland or coastal, dust covering plants
Very troublesome pest
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6. California scale Control
Biological-Red & blue ladybird beetle larvae ( Chilocorus spp). The adult beetle lays her eggs under scale cover= larvae feed
Aphytis melinus wasp lays her eggs under the scale cover of a second instar unmated female scale= hatched larvae feed, adult wasp also feed
Cultural- Keep trees healthy, do not over fertilise / over-water,
Control ants. They severely disrupt red scale parasites while tending red scale
Avoid excessive dust build up on leaves and fruit, (eg from manure mulches, kaolin clays)
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7. Californian scale - Control
Cultural - Fine, talc-sized particles of ash from bush fires can also disrupt biological control. Washing trees to remove dust or ash particles can help solve this problem.
Heavy fogs, drizzle, or rain can also help by either removing dust and ash particles or causing them to adhere to the leaf surface.
Chemical- White/pest oil ( not on blossom)
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8. Citrus leaf miner Order- Lepidoptera
Appearance –usually observed when leaves are damaged by larvae tunnels and pupal stage
Damage-The larvae tunnel down new shoots near tips or junctions = wilting , distortion and obvious tunnelling
Plants affected Citrus
Common on coast and has a major impact inland on citrus orchard industry
. In early summer the newly hatched first generation larvae bore into the tips of terminal shoots and tunnel downward until they reach harder woody tissue, at this point they exit the shoot and enter another one. The tips of infested shoots soon wilt and die. A single larva may destroy two to five shoots before it matures. The mature larvae exit the shoots and drop via silken threads to the ground or the trunk of the tree, where they spin cocoons and pupate. Summer cocoons are more fragile than overwintering ones. The life cycle is repeated and the second brood larvae hatch. This generation also attacks shoots but by midsummer the new shoots begin to harden. At this time many of the partly grown larvae exit the shoots and attack the young fruit. They may tunnel to the pit or feed near the surface, producing large masses of gum mixed with sawdust-like castings (frass). Emerging larvae of later broods may bore into the soft stems of the fruit, being too small to attack the hard fruit directly. As the fruit ripens and softens it no longer produces gum when attacked and young larvae can enter it directly. Larvae that bore into the stems may tunnel down into the ripening fruit. Larvae of later broods attack the ripe fruit leaving no visual signs of infestation and it is not until the fruit is cut open that the larvae are discovered.
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9. Citrus leaf miner - Damage
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10. Citrus leaf miner

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12. Life cycle Damage occurs in later summer and autumn
Larvae tunnel in surface layer of new leaves
Pupal chamber is formed at the end of the larval stage where the larva wraps itself in a silk casing at the edge of the leaf.
Adult lays eggs along leaf margin 0.3 mm in size
14 – 17 days complete lifecycle
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13. Control Winter fertilising to promote new growth in spring
Prune off affected leaves and destroy
Natural predators can control from 20 – 90% of all infestations
White oil is the only recommended chemical control for home nurseries
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14. White Louse Scale
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15. White Louse Scale Generally found on trunk and lower branches first
Spread to upper twigs and leaves
Generally plant has branch die back and poor vigour
Control is white oil treatment
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18. Queensland fruit fly Order- Appearance Damage Plants affected CONTROL
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24. Lemon scab
FUNGUS
Appearance/ Damage-Irregular scabby areas on fruit, sometimes leaves & twigs . Wart-like outgrowths sometimes scabbed. Severe shedding of young fruit, external quality affected
Plants affected-Citrus ( mainly lemons & mandarins)
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26. Spread- Rain, wind
Control- Occurs during damp weather & only on immature fruit, coastal areas. When symptoms seen it is too late to save infected fruit. Need for preventative spraying before next crop.
Chemical- Apply Bordeaux (+ white oil) in spring ant half petal fall and again in late Jan/early Feb at blossoming of second crop
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27. Melanose
FUNGUS
Appearance/ Damage-Small Reddish to dark brown spots on leaves & fruit. Streaky if spores are washed by rain, skin of fruit may become cracked and have a ‘mud-cake’ appearance
Young leaves & fruit are susceptible & usually occurs on older trees in wet warm conditions
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28. Melanose Mudcake or sandpaper symptoms of melanose on grapefruit.
Tearstaining caused by melanose spores washed down the fruit by dew or rain.
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29. Melanose
Plants affected-Citrus-Washington navels,Emperor mandarins & lemons
Spread- Water – dripping & splashing
Control- remove & destroy infected parts,Copper oxychloride + white oil at petal fall
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30. Bronze Orange Bug Piercing and sucking mouthparts True bug Gregarious
Damage the tips of new growth and cause leaf distorton
Toxic urine from adults and older nymphs (eyes and hands, sensitive skin)
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34. BoB Control Hand removal shaking and spray with high pressure water
Chemical use only white oil
White oil affects most predators as well
Affect new growth so prune damaged growth.
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35. Spined Citrus bug
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36. Summer fruit drop
Citrus normally shed large numbers of fruitlets shortly after blossoming in the spring and at early fruit set (pea size).
when warmer weather places stress on the tree.
related to lack of water at, or soon after, fruit set.
Root diseases and lack of nitrogen or trace elements may also be responsible. .
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37. Rind splitting
Rind splitting of fruit, particularly in navels, also occurs before or near maturity as a result of climatic factors, specifically a drop in average temperatures and an increase in relative humidity at a time when the rate of fruit growth is decreasing.
There is no control for the disorder.

38. Preharvest drop
Preharvest drop in the autumn before fruit is fully mature is a common problem with navels and grapefruit. Some of this drop is natural, but in coastal areas fruit stung by Queensland fruit fly during the late autumn colour-change period is also very prone to drop. Some mandarin and lemon varieties will also shed fruit when damaged by the spined citrus bug. Brown spot infection in mandarins will result in fruit drop.

39. Alternate cropping (biennial bearing)
Alternate cropping (biennial bearing) is a common problem with many citrus varieties, such as Valencia orange, Wheeny grapefruit, and mandarins.
Pruning or thinning of the heavy crop and early harvesting will assist in reducing the problem.

40. Second crop fruit
Sometimes orange trees will produce blossoms in the autumn after a stress period, and set a second crop. This fruit is often of poor quality (thick skins and low juice content) and is susceptible to fruit fly attack. With lemon trees, however, these intermediate crops are desirable

41. Grape vine moth Order- Lepidoptera
Appearance – Adult- black moth with yellow markings & tuffs of orange hair at the tip of the abdomen. Larva – blend of green, yellow, black with red markings at sides and a red band over body at hind end. Scattered white hairs over body.
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42. Grape vine moth
Damage- Larvae skeletonise leaves, defoliate to main stems
Plants affected- Grapes, Fuchsias, Parthenocissus
Prefers lush growth
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43. Grapevine moth control
Biological- Dipel, birds, wasps
predatory shield bug Oechalia schellenbergii.
Natural predators are usually effective
Physical- hand pick off from leaf dersides
Chemical-Only spray in severe infestation
Oechalia schellenbergii.
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44. Grapevine moth control
Larva being eaten by mating shieldbug
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45. Phylloxera Order- Hemiptera
Appearance –This aphid can live below or above ground & when swelling or galls are cut open aphids =green - yellow
Damage- Roots- have fleshy yellow galls on the fine roots ( may be curved in a S shape).Leaves have fleshy yellowish irregular swellings. Infected plants are weak & do not produce good crops
Plants affected- stressed grape vines (which are less able to repel their attack), in heavy soils & humid environments and warm temperatures.
AN EXTREMELY SERIOUS PEST OF GRAPEVINES
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46. Phylloxera
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47. Phylloxera -Damage
Root-feeding stages are the most damaging, causing a loss in plant vigour, wilting and leaf yellowing. Vines may eventually die within 3-10 years. The aphids live on the surface of root galls and inside the leaf galls.
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48. Galls on infected leaves
Phylloxera -Damage
Galls on infected leaves
Galls on infected leaves
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49. Phylloxera -Damage
The effect of phylloxera aphids feeding on the roots is to cause the vines to get progressively weaker, and they produce fewer leaves and grapes.
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50. Phylloxera control
There is no chemical control & no economic means of removing it from the soil once it is established
Cultural- QUARANTINE regulations, grow on resistant root stocks
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51. Anthracnose VARIOUS FUNGUS
Appearance/ Damage-Small to large, dark circular spots or sunken lesions with raised rim on leaves, stems & fruit
Can occur at any stage of growth, twig die back, corky spots on fruit, fruit drop & rot
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52. Anthracnose leaf spot on watermelon leaf
Stem and pods have black fruiting bodies, “acervuli,” with black hairs, “setae.
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53. Anthracnose
characterised by discrete lesions that are usually found along leaf veins. In severe cases these lesions may run together and kill the entire leaf. Young leaves may become distorted as healthy tissue continues to grow around dead areas.
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54. Anthracnose
Colletotrichum acutatum
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55. Anthracnose
Sunken lesions, slightly paler than the healthy tissue, are symptoms of tomato anthracnose.
Black fruiting bodies are visible on this close-up of the lesion.
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56. Anthracnose
Tomatoes develop sunken spots on ripe fruits, the central parts of which turn dark.
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57. Anthracnose Plants affected- Citrus, grapes, stonefruit, avocadoes etc
Spread- Water, wind, animals, tools, infected plants
Control- remove & destroy infected parts, crop rotation, disease free seed, improve drainage, air circulation, watering
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58. Peach leaf curl
Control- remove & destroy infected parts,Copper oxychloride before bud swell or late Winter
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