There are many important economic species. Host deterioration and crowding factors. Note that live bearers may give birth every day with infant being pregnant before being born. Can feed on leaves, stems, buds, fruits, and roots. The corn root aphid feeds on corn roots.
Ants collect the eggs of the aphid and tend overwinter in nests.
The ants then transfer the young aphids to various weeds in spring and later to corn late in the season. This is a diverse and highly specialized group of insects. Females are often wingless and adult males lack mouthparts . The first instar is called a crawler . It is active and moves around the plant to search for a feeding spot.