Integrated Pest Management
Giant Conifer Aphids
Giant conifer aphid infestation on blue spruce (Bob Hammon, Colorado State University, Bugwood.org)
Cypress aphids (James Denny Ward, USDA Forest Service, Bugwood.org)
Cinara aphids on fir (USDA Forest Service - Ogden, Bugwood.org)
Pest Description
- up to 1/5 inch long; large aphids with long legs
- purple to black in color; bodies may have a coating of grayish-white powder
- winged or wingless
Host Plants, Diet & Damage
- found on many species of conifer, including juniper\
- feed on bark, twigs, foliage and roots
- honeydew production can lead to black needles (sooty mold)
Biology, Life Cycle & Damaging Life Stage
- overwinter as eggs on bark or needles
- emerge in spring from eggs
- often found in large groups on host trees
IPM Recommendations
- Giant conifer aphids have little negative effect on tree health; tolerate pest.
- Spray with high pressure water to dislodge aphids.
- Use insecticidal soap.
- Apply a systemic insecticide (neonicitinoid) in the spring.