Peaches are an important crop in Texas, worth $39 million a year to the state's economy, the Texas Department of Agriculture reported in 2010. While most commercial orchards are located in the eastern, central and the central-northwestern regions of the state, farmers and gardeners throughout the state grow peach trees. These Texas peach trees are susceptible to plum curculio and other worm-like pests, including peach tree borer larvae.
Peach Tree Borers
The peach tree borer (Synanthedon exitiosa) and the lesser peach tree borer (Synanthedon pictipes) attack peach and other stone-fruit trees, especially in the eastern part of the state, according to the Integrated Pest Management (IPM) Centers. The adult peach tree borer moths begin working their damage in August or September, when the moths mate and lay eggs on tree trunks, notes the Texas Agricultural Extension Service.
Within 10 days, the larvae hatch and burrow through the bark into the tree trunk. They spend 10 to 11 months feeding inside the trunk before they resurface to mature into moths. The larvae produce clumps of sap at the trunk base of affected trees. The lesser peach tree borer feeds on limbs. These wood-boring pests can damage limbs or even kills trees, the extension service warns.
The service recommends applying a contact insecticide once in August or September to keep peach tree borers at bay. Those insecticides include chlorpyrifos, endosulfan and lindane.
Those worms wriggling around inside the peach fruit may be immature plum curculio beetles (Conotrachelus nenuphar). The beetles lay their eggs on young peaches and the hatched grubs make their way to the center of the fruit. Eventually, the peaches will fall off the tree. Peaches that do make it to harvest are deformed, or "catfaced."
Clean up infested peaches to keep the plum curculio from continuing to infest your trees. Spraying can help, but you must apply Sevin or Malathion before the beetles lay their eggs. The plum curculio problem occurs most often in east Texas, according to the IPM Centers.
Oriental Fruit Moth
Larvae of the Oriental fruit moth (Grapholita molesta) also bore into branches and fruit, especially late-blooming peach trees. Newly hatched larvae prefer young shoots and will enter twigs at their tips and chew their way through the twig until they consume all the available food. The still-developing larvae will move on to another twig or fruit. The twig damage can make trees appear bushy. The infestation can also cause branches to die back and fruit to drop.
The IPM Centers says controlling other peach pests can help keep the oriental fruit moth from infesting your trees. You can also use pheromone traps to check for moth infestations.