Damage to direct seedings may be severe. The first cut of established fields escapes injury but as leafhoppers become more prevalent in late June to mid-August, damage may be severe. The potato leafhopper is a light green, wedge-shaped insect about 0.3 cm long when fully grown. The immature or nymph stage is yellowish-green and wingless but otherwise resembles the adult. Adult leafhoppers may jump or fly.
Nymphs walk sideways or backwards to hide on the underside of the leaves.
This insect feeds by sucking plant juices. The alfalfa is stunted and the leaves turn yellow to bronze in colour. A discoloured V-shaped or triangular area often develops on the tips of leaflets. While this marking is characteristic of leafhopper presence, the leaf discoloration may also be a symptom of disease or nutritional deficiency. Effective control of the potato leafhopper depends on recognizing the adults and nymphs before symptoms become apparent.