Honeylocust Spider Mite

Pest Description

• 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

• honeylocust
• 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

IPM Recommendations

• 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.