Leafhopper Newsletter

Adult and nymph populations have peaked, but adult densities remain elevated - Sept 28

MENDOCINO COUNTY

Densities of both VCLH and WGLH eggs and nymphs have declined at most sites while adult populations remain relatively elevated, and may even increase as remaining nymphs molt into adults. The leafhopper adults present at this time are most likely in reproductive diapause and will overwinter in the vineyard.

LAKE COUNTY

VCLH adult densities are generally low and more variable across all sites (less than 3 adults per trap). No VCLH nymphs have been observed since mid-July, with the recent exception of Scotts Valley and Finley, but densities are still very low (less than 0.5 nymphs per leaf). WGLH adult and nymph populations have peaked at most sites with the exception of Finley, where no WGLH nymphs have been observed since June.

PARASITOID RELEASE PROGRAM

No further parasitoid releases are scheduled for 2016 in order to build up populations in our greenhouse colonies in preparation for the fall-winter period.