Begin checking weekly for caterpillars, black cherry aphids, thrips, and earwigs during bloom.
How to Monitor
Just before bloom:
- Map out four quadrants of the orchard.
As soon as blossoms open, check each quadrant for:
- Presence of earwigs
- Presence of caterpillars:
- Fruittree leafroller: leaf and bud chewing damage; webbed leaves; larvae.
- Green fruitworm: large holes in leaves; larvae.
- Obliquebanded leafroller: damaged blossoms; larvae.
- Orange tortrix: damaged blossoms; larvae.
- Western tussock moth: egg cases on leaves and twigs; larvae.
- Presence of black cherry aphids: curling and distorted leaves.
- Presence of western flower thrips: adults and nymphs.
- Note natural enemy activities of the caterpillars and aphids.
Treatment Decisions
| Black cherry aphid | If natural enemies are not adequately controlling the population, apply a treatment shortly after petal fall, when aphids first appear according to the PMG. |
| European earwigs | Treat at beginning of spring activity when earwigs are found according to the PMG. |
| Fruittree leafroller Green fruitworm |
When larval damage is evident in orchard, apply an insecticide at petal fall or shortly thereafter according to the PMG. |
| Obliquebanded leafroller (Central Valley) Orange tortrix (coast) |
Treat orchards that had large populations of larvae the previous summer or where the previous year's crop was infested according to the PMG. |
| Western flower thrips | No thresholds; significance of damage is not known. |
| Western tussock moth (coast) | Petal fall sprays to control other worm problems generally control this pest. Localized infestations can be pruned out and destroyed. This pest is cyclic and often controlled by parasitic wasps. |