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Cultural Practices
Good cultural practices include planting on a well-drained site, proper fertilization, proper pruning and training, removal of any diseases or insect-infested fruit or branches, proper control of weeds, and planting disease-resistant cultivars when possible.Peaches should be planted on a well-drained site, where soil has a depth of 2 feet or more. Peach trees do not tolerate wet "feet"; avoid wet, seepy spots, water drainage areas and heavy clay soils. Where these areas or soils cannot be avoided, bring in good soil to make a berm. For proper fertilization, make all fertilizer applications to peaches in early spring before growth begins.
Insect Pests
There are several insect pests that can cause damage to peach trees. The oriental fruit moth causes die-back of young growing tips and wormy peaches. Plum curculio lays its eggs in cresent-shaped cuts on the young fruit, causing them to drop or be wormy. Borers attack the base of the trunk and the crotches of the main scaffold branches.
Peach, Cherry, and Plum Insects
Apple Curculio
The Apple Curculio is found in the midwestern and western United States and in eastern Canada. As soon as the surface temperatures stays at 60° F or higher for 24 hours, the adults will simply crawl around on debris. If the temperatures are high above 60° F, they will fly a short distance. They attack fruit as soon as it develops. The larvae and adults attack, eating small holes in the sides or ends. The puncturing does not make the fruit fall, but will arrest the growth at the point
punctured. Apple Grain Aphid (Rhopalosiphum fitchii)
The adults are green and have dark green lines running vertically and horizontally down the back; one down the middle and five across. They prefer cold, wet weather. The apple grain aphids overwinter in the egg stage.
Damge: As soon as the buds open, the young aphids start to feed on the leaves. Feeding does not
cause any leaves to curl and does not cause any serious damage to the tree.
Control: The aphid is not an economic pest and will leave the orchard shortly after petal fall.
Therefore, no control measures are necessary.
Apple maggot (Rhagoletis pomonella)
The adult apple maggot is a fly, slightly smaller than a house fly, that lays tiny yellow eggs on developing fruit. Apple maggot is primarily a problem in northern Illinois. Adult flies emergence from their overwintering sites in the soil in June, with the heaviest emergence in late June. Emergence continues through August, some may appear in September. Female flies deposit eggs just under the fruit skin; the eggs hatch in 5-10 days. Larvae tunnel through the fruit flesh and mature after fruit falls. One generation per year is usually completed in Illinois, but some areas may have a partial second generation.
Damage: Pits and dimples form on the apple as a result of egg laying damage, leading to misshapen
fruit. Larvae damage the flesh by leaving large brown trails allowing decay to occur. When numerous,
the fruit grows extremely dimpled and gnarled, and the flesh is ruined.
Scouting/Monitoring: Red spheres covered with sticky material placed around the outside of the tree may help reduce apple maggot damage.
Action Threshold: Insecticides should be applied when 2 to 5 flies per trap have been caught.
Subsequent sprays are needed whenever more than 2 flies per trap are captured 10 to 14 days after the last spray.
American Plum Borer (Euzophera semifuneralis)
The larvae of the American plum borer overwinter in silken cocoons beneath the bark until the spring. The larva is 18-25 mm long and varies in color from white/gray to gray/purple. Larvae feed on burr knot tissues resulting from the dogwood borer.
Control: Apply an effective pesticide.
Black Cherry Aphid (Myzus cerasi)
The adult aphid is black, 3 mm long, and is either winged or wingless. They prefer to feed on sweet cherries, but feed on tart cherries as well. The aphids favor high temperatures combined with high levels of moisture. The eggs overwinter on buds or bark of smaller branches and hatch around the time the buds open.
Control: In June, hang canary-yellow sticky traps baited with feeding attractants. One feeding
attractant Cherry fruit flies will respond to is a teaspoon of ammonium acetate or ammonium
hydroxide.
Cherry Fruitworm (Grapholitha packardi)
The 1.4 mm long, gray larva overwinter in hibernaculum until spring. After pupation, the adult emerges in the form of a small, grayish black moth and is ready to mate. Soon after, the females lay eggs. The eggs are laid on unripe fruit where they prepare to hatch.
Damage: After about 10 days, the eggs hatch and the larvae bore into the fruit, leaving small, brown
trails and damaged fruit.
Control: Chemicals must be applied and timed according to the emergence of the adults. Insecticides
should be applied 10-20 days after petal fall.
Cherry Leafminer (Nepticula slingerlandella)
In the pupal stage, the cherry leafminer overwinters in orchard litter. Adults emerge from overwintering from late May to mid-June. The adults are small, tan colored moths with wing spans of 3.5 to 5 mm. The forewings have a black band rinning across the outer third. After overwintering, the female lays an average of 15 to 20 eggs and up to 80. Eggs are laid on the undersides of leaves.
When larva emerge from their shell they bore into the undersides of the leaves they're deposited on.
From there they move immediately to the upper epidermis of the leaf and mine the tissue directly below it. The larva is a small, round, annulated caterpillar. The first instars are transparent; later instars become a more greenish white. The full grown larva is about 4 to 5 mm long and about
0.4 mm wide.
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