Corn root aphid
- Adult: Bluish-green or gray, soft-bodied, round insect about the size of a pinhead. Subterranean and remain in the soil year-long. Secrete a sticky sugary substance called honeydew and feed on plant juices through the roots.
- Nymphs: Similar to the adults but smaller.
- Eggs: Females do not lay eggs but give birth to live young.
Timing of damage: All growing season
Type of damage: Attacks roots and sucks out the sap. Aboveground, plants become tinged with yellow or red and growth is stunted.
Scouting: Dig up 2' of plants in five locations and record the number of plants with live aphids and showing symptoms.
Economic threshold: None established.