Western Grape Leafhopper – Erythroneura vulnerata
Western Grape Leafhopper –Erythroneuravulnerata
Common Name: Western Grape Leafhopper
Latin Name: Erythroneuravulnerata
The adult grape leafhopper measures around 0.12 inches (3 mm) in length and is light to pale yellow with dark brown and reddish patterns. Eggs are placed singly in epidermal tissue on the underside of leaves and appear as a bean-shaped, blisterlike protuberance 0.04 inch (1 mm) in length. The first brood’s eggs are deposited on basal leaves in April and May. The thorax of a nymph is white with six faint yellow dots and clear eyes.
Damages caused by Western Grape Leafhopper:
All three species’ nymphs and adults take the contents of leaf cells, leaving behind empty cells that look like pale yellow dots or stippling. The entire leaf may be pale yellow or white when the population is dense. When leafhopper populations are exceptionally high, leaf efficiency and drop might result. If the total photosynthetic capability of the vine is significantly reduced, immature or stressed vines may have decreased shoot development the next season. The buildup of microscopic droplets of feces on berries and the formation of sooty mildew causes berry spotting, which is a problem in table grapes. Adult leafhoppers are also a nuisance to harvesters when numbers are large.
Life history and habits:
Grape leafhopper has 1.5 to 2 generations each year, with adult abundance peaks in late July and August. Adults overwinter in leaf litter in or around vineyards and feed on weeds in the spring when temperatures rise above 60o F (16o C). After mating in late May and early July, they travel to young grape foliage to deposit transparent, crescent-shaped eggs inside the leaves. First-generation eggs hatch mid-to-late June, and the flightless nymphs mature into adults over a month. Leafhoppers are harmed by cold, damp springs and winters.