Life history and control of the pear borer in Virginia: Aegeria pyri Harris (Lepidoptera: Aegeriidae)
- The pear borer is widely distributed in the eastern part of this country.
- The abdominal cavity of the female was filled with eggs.
- The incubation period of the eggs averaged 5.6 days at a mean temperature of 76.2 degrees F.
- The larvae fed mainly on the inner bark and cambium of the trees, but occasionally burrowed slightly into the sapwood.
- There were six larval stages.
- Larger larvae devoured smaller larvae on contact with them.
- Around 85 percent of the borers have a one-year life cycle.
- The winter was passed by the larva in a silken hibernaculum constructed in the burrow.
- The pupa was strongly chitinized, and the abdomen was armed with large spines.
- The pupal stage averaged 23.0 days for the males and 17.44 days for the females.
- The moths were most active and most of the eggs were deposited between 2:00 and 4:00 p. m.
- On the female moth there was more yellow than on the male.
- The average length of life for the males was 4.46 days and for the females 4.96 days.
- In the andrews orchard 50 to 100 borers per tree were not unusual.
- The apple is the main host plant of the larvae in Virginia.
- About 99 percent of the moths emerged between May 15 and July 10.
- The male moths emerged several days before the female.
- The females had deposited 33 percent of thelr eggs when they were captured in the bait-pails.
- The pear borer is sometimes rather extensively attacked by hymenopterous parasites.
- The borers may be removed with a sharp hawk-bill knife in the fall or early spring.
- In heavily infested orchards, bait-pails would be economical and quite effective in reducing the number of moths present in the orchard during May and June.
- The common insecticidal sprays are not effective in killing the larvae.
- Paradichlorobenzene dissolved in cottonseed oil, white mineral oil, and pine tar oil and applied to the trunks and larger limbs of the trees with a paint brush gave excellent results without injury to the tree.