Leafhoppers

Hosts

Apple, cherry

Biology

White apple and rose leafhopper are the most common species.  Nymphs begin feeding on leaves by petal fall.  They are white and crawl slowly (rose leafhoppers have black spots).  The adults are wedge-shaped with wings meeting in a sharp peak over the back.  There are two generations per year.

Symptoms/Damage

White stippling on leaves; frass (tar-like spots) on fruit; flying adults are a nuisance during picking; reduce tree vigor.

Monitoring

Look for nymphs at petal fall on undersides of leaves or shake branches over a cloth tray.

Treatment Threshold

No fruit injury occurs even in heavy feeding, so treatment early in the season is done to prevent a nuisance population during picking.  An average of 3 nymphs/leaf may require treatment, but trees can tolerate a much higher density.

Degree Day Model

None

Management Considerations

Nymphs are easier to control than adults.