• Pest Type: Insect
• Crops Affected: Soybeans, Alfalfa, Peanuts
• Scientific Name: Spissistilus festinus
• Pest Order: Hemiptera

Description
Adults are green, triangular-shaped (blunt in front and pointed at the rear), and range from 6-6.5 mm in length. Eggs are white, oblong-oval, and 0.9-1.3 mm long; and they are slightly larger at one end, that end having a rough surface. Nymphs are straw-colored, wedge-shaped, and heavily spined, with white legs, antennae, eyes and abdomen. The mature nymph is s active and about 4.6 mm long.

Damage
Threecornered alfalfa hoppers girdle stems by their feeding and egg-laying activities. Nymphs and adults weaken the lower stem by piercing it with needle-like mouthparts and extracting juices. As a result, lodging and breaking usually occur weeks after infestation. If damage is scattered, soybeans can often stand up to 25% damaged plants before yield is significantly reduced. Therefore, this pest rarely cause economic damage.

Life Cycle
This pest overwinters as eggs in plant tissues or as adults in clumps of grasses. Young nymphs from overwintered eggs or overwintered adults begin feeding in the spring. Females deposit 30-40 eggs singly in host plant stems. Nymphs hatch 2-6 weeks later. They feed for 3-10 weeks before fifth instar nymphs molt to adults. On average, 50 days elapse between egg deposition and adult emergence. The adults are strong fliers and readily migrate to new fields. There are generally two generations per year.

Control Measures
Damaging infestations of the threecornered alfalfa hopper can be avoided by destroying weedy borders around fields and by seeding a little more heavily. If scouting shows high infestations of this pest, contact local advisers regarding thresholds and chemical controls, if necessary.