Oriental fruit moth, Grapholita molesta (Busck): Although primarily a pest of peach, the incidence of adults and injury (identical to codling moth) from this insect has been increasing in apple orchards. Apple orchards adjacent to peach are most vulnerable to attack, especially if peaches are not sprayed because of crop loss due to cold temperatures. The elimination of some insecticide applications because of below trap threshold populations of codling moth may be contributing to increased levels of oriental fruit moth. The specific timing of current insecticide applications (based on degree days) for codling moth and leafrollers may be permitting the survival of oriental fruit moth, which had been previously controlled by calendar-type applications. The possibility exists that oriental fruit moth may be developing resistance to some of the commonly used organophosphate insecticides.

Apple maggot, Rhagoletis pomonella (Walsh): Except for a few isolated situations, apple maggot has not been a problem in the past in commercial apple orchards in West Virginia. Prior to 1998, it was not known if this lack of pest importance was due to low incidence in this region, or just low populations in commercial orchards because of insecticide applications for other pests, which also effected apple maggot. A trapping survey of 12 commercial and 12 abandoned apple orchards in 1998 revealed the presence of apple maggot in all sites. Fly populations were high in most abandoned sites and low to moderate in commercial sites. Some commercial orchards adjacent to abandoned orchards sustained significant fruit injury. It appears that the widespread occurrence of apple maggot in West Virginia is generally being maintained at low levels in most commercial orchards by insecticides applied for the control of other insects. Orchards that become abandoned because of increasing urbanization will pose the threat of apple maggot infestation to adjacent commercial orchards. The survival and future pest status of apple maggot in commercial orchards will be significantly influenced by the fate of organophosphate insecticides, as newer, more selective replacements for controlling other pests are ineffective against apple maggot.