Lettuce root aphid
11 host plants
Last updated
Lettuce root aphids feed on the roots of poplar and other host plants in Western Washington, causing stunted growth and wilting despite adequate moisture. The small, light-colored aphids colonize roots and are not visible without excavating soil. You notice plant symptoms rather than the insects themselves; affected plants show wilting, yellowing, or poor growth development during the growing season.
Reduce soil moisture by improving drainage and avoiding frequent, light irrigation. Allow soil to dry moderately between waterings to discourage aphid populations. Remove severely infested plants if they do not respond to cultural management. For high-value ornamental poplars, soil drenches with spinosad can suppress populations. Most populations self-regulate through natural enemies.
Quick Reference
Cultural Controls
- biological control Many parasites and predators attack aphid.
- Monitor the proportion of aphid mummies to unparasitized adults and the number of predators such as lady beetles.
- If the biocontrol agents appear to be gaining control, avoid sprays which would disrupt this system.
- Most products available for aphid control are highly disruptive of natural enemies.
- Management-cultural control Aphid populations tend to be higher in plants that are fertilized liberally with nitrogen.
- Prune out suckers...