Monitor the orchard early in the season as trees come into bloom to help detect potential pest problems early.
- Monitor the orchard for plant bug and stink bug (view photos).
- Monitor trees for the presence of peach
twig borers, fruittree leafrollers, or obliquebanded leafrollers, katydids, and
western flower thrips (view photos). 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.
- For thrips, examine blossoms from each tree by slapping a shoot with five to ten blossoms against a yellow card or look for the immature stages within the blossoms.
Montoring 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 |
|---|---|---|
| Katydids | Katydid feeding consists of small holes in the center of young leaves. | If any of the leaves examined show signs of feeding, treat. |
| Western flower thrips | Thrips in the blossoms. | If a single immature thrips is found, treat. . . . or . . . If two blossoms out of 50 sampled have adult thrips, treat. |
| 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 young foliage and begin to tie leaves together. | Thresholds have not been determined. |