Monitor the orchard early in the season as trees come into bloom to help detect potential pest problems.
- Sample the orchard ground cover with a sweep net for plant bug, stink bug, thrips, and katydid populations (view photos of ground cover pests).
- Monitor trees for the presence of peach twig borers, fruittree leafrollers, or obliquebanded leafrollers, and katydids (view photos of leafrollers and katydids). Examine flowers and leaves on 2- to 3-year-old branches located at head height on each of 50 trees as you walk through each varietal block. For peach twig borers and leafrollers, pull off a few flowers and examine for feeding, holes, or the presence of caterpillars. For katydids, spend about 30 seconds examining leaves for feeding damage. Monitoring at this time will let you know the effectiveness of the dormant or bloom treatment and alert you to the need for additional treatment.
|Pest||What to look for||Treatment threshold|
|peach twig borer larvae||At this time peach twig borers feed at the base of flowers where they bore into the calyx, creating small holes. They may also enter the tips of shoots causing them to wilt (see SHOOT STRIKE MONITORING).||If any are present, a treatment is necessary at first flight.|
|fruittree leafroller, obliquebanded leafroller||Fruittree leafroller and obliquebanded leafrollers feed on blossoms as well as the young foliage and begin to tie leaves together.||Thresholds have not been determined.|
|katydids||Katydid feeding consists of small holes in the center of young leaves.||If any of the leaves examined show signs of feeding, a treatment may be warranted.|
|western flower thrips||Thrips in blossom.||If four
or five blossoms out of 50 sampled have mature thrips, treat;
. . . or . . .
If more than three blossoms are found with immature thrips, treat.