Aster root aphid

Prociphilus erigeronensis, commonly known as the aster root aphid, is a member of the Aphididae family. It is a specialized pest that colonizes the roots of host plants, often remaining undetected until the host plant shows significant signs of stress or sudden decline.

This pest primarily targets plants within the Asteraceae family, most notably asters and fleabanes (Erigeron). While it prefers these specific hosts, it can occasionally impact other herbaceous plants when populations become dense and food sources on preferred hosts are exhausted.

The biology of this species is heavily dependent on mutualism with ants. The ants provide protection and assist in moving the aphids between roots, effectively maintaining the colony. These aphids reproduce parthenogenetically during the growing season, allowing for rapid population growth and expansion.

The damage caused by these insects involves the depletion of plant nutrients by sucking sap from the root systems. Symptoms include stunted plant growth, wilting during hot weather, and yellowing foliage. Damaged roots are also highly susceptible to secondary fungal infections which can kill the plant.

Effective management strategies focus on both cultural and chemical control. It is essential to manage ant populations around sensitive plantings to prevent the spread of aphids. Deep tillage or cultivation around root zones can disrupt colonies, and the use of systemic insecticides as soil drenches is often required to reach the aphids feeding below the soil surface.