Picture of grape demon from reader |
Grape leafhopper damage see the yellow speckling from feeding damage and black poop spots |
A. The picture was a bit blurry but appears to be grape leafhopper. However the description of the damage sounds like grape flea beetle. If leafhoppers the insects are small, maybe ΒΌ inch long. In their mature stage they can jump short distances. There can literally be thousands of them on a grapevine many of them jumping when you walk by the vine landing on your face and clothes. Very irritating.
Grape fleabeetle damage leaves holes in the leaves |
They can be curtailed by applying an organic biological control of Spinosad in early May and again mid-May when the nymphs or immature forms are present. It will control the nymphs but does not do much to the adults. If you get it applied early enough this will reduce the population when the adults mature. Make sure you spray the underside of the leaves as well as the tops.