Honeylocust Spider Mite
Overwintering female honeylocust spider mites (Whitney Cranshaw, Colorado State University, Bugwood.org)
- adults: very tiny, ~ 1/80 – 1/60 inch; pale green to yellowish green
- immatures: smaller and pale green
- eggs: smaller than adults and greenish
Host Plants, Diet & Damage
- feed on undersides of leaves typically near the mid-rib
- stippling causes yellowing of leaves and canopy
- most damage caused by mid-summer
- may cause premature leaf drop in late summer
Biology, Life Cycle & Damaging Life Stage
- overwinter as orange-colored females on or under bark or bud scales
- adults become active around budbreak
- eggs are laid on leaves and hatch around early-June
- one generation can occur every week to 2 weeks
- prefer hot, dry weather
- populations build through July and decline in August
- can disperse via wind
- overlapping life stages present in late spring throughout the growing season; many generations per year
- immatures and adults are the damaging stages
- Manage trees to improve or maintain health.
- Monitor spider mite populations on host plants with a “paper test” starting after budbreak. To conduct the test, hold a white sheet of paper under affected branches and shake vigorously. Tiny specks moving around on the paper indicate the presence of mites.
- Preserve beneficial mites and organisms.
- Apply a dormant oil to target overwintering adults. Apply an insecticide/acaricide (dicofol; horticultural oil; insecticidal soap; METI acaracide; organotin miticide; pyrethroid) when mites are present on leaves.