|
What is it?
Grape leafhoppers are of the erythtoneura species and feed by sucking the grape juices from plants. Grape leafhoppers can retard or stunt the growth of grape plants and affect maturity of the fruit which can hinder your grape harvest.
What does it look like?
Erythtoneura species grape leafhoppers look somewhat similar to the common and more well known, grasshopper. However, they are a pale green with crisscrossing or similar markings of orange and black which in some cases can make these garden pests almost seem as if they have a marbelized look to them. Some grape leafhoppers vary in shade to a pale yellow green or almost whitish shade and can also have yellow markings. These insects of the erythtoneura species are usually only about 1/8 inch long and fly as well as jump. More often than not, you will not see grape leafhoppers jumping or flying, but may notice them when you go to pick grapes and find them attached to the undersides of leaves where they feed and suck the sap from the plant. Damage from grape leafhoppers usually presents itself with stippled or mottled looking leaves which turn pale yellow and white and die as they become brown and dry, having no more sap to sustain them. Grape fruits may also have black spots on them.
How does it manifest?
Erythtoneura species grape leafhoppers are dangerous to grape plants as both young and adult varieties. As they suck sap from the plant, the vine is starved of necessary nutrients for survival and vine growth is thereby reduced. This process of feeding results in delayed fruit maturity and overall stunted growth of the grape plant. A good indicator of a grape leafhopper infestation are their tell tale droppings which as small and black and may be found on fruit, leaves or vines. Although this may appear unappetizing it does not necessarily affect the quality of the fruit unless the vine on which the fruit exists is sapped severely. Grape leafhoppers can survive harsh winters as adults as long as they find a protected area to overwinter. As soon as new plant growth begins in the spring, the adult grape leafhoppers will emerge and commence feeding. Adult females then lay their eggs amongst the grape leaves which cause the leaves to appear to have a blister, as the eggs are laid in swelled pouches. Two or three generations of grape leafhoppers will be created in this manner each growing season.
What can you do about it?
Grape leafhopper damage can be controlled through the use of a diazinon or malathion containing insecticide. When applying the insecticide treatment you should be aware that you will need to saturate both the top and undersides of the leaves. Applications of insecticide can be repeated safely at ten day intervals as long as the plant continues showing signs of infestation, or in the event it becomes reinfested. The best way to avoid grape leafhoppers overwintering and emerging to feed on your plants again the following year is to diligently remove any fallen plant debris and destroy it after the harvest.
| 
