Surveying: Leafhopper populations

Rapid and accurate surveying for grape leafhopper population levels is essential to a decision for necessity of insecticide treatment within an integrated pest control program. These Tulare County studies indicate that counting the nymphs on only two leaves per acre gives as accurate an estimate of the population as did counting the nymphs on fifty leaves. It was also found that the leaves could be selected from vines along the avenues, rather than from vines scattered throughout the vineyard.