Q. For the second year in a row, my grape plants were decimated, but starting right before ripening, and continuing throughout the summer.  I sprayed a soap spray on them, but to no avail.  I thought the problem was a slow flying black fly, but then I noticed a blue and yellow caterpillar type bug on one of the leaves.  What can I use to prevent this from happening again, and will they threaten my peach trees (not so far) Attached are a couple of photos.  The match book is for size comparison. A. This is the grape leaf skeletonizer. Here are some posts on my blog that address this for Las Vegas. Let me know if you have trouble seeing these. http://xtremehorticulture.blogspot.com/2014/04/grapeleaf.html http://xtremehorticulture.blogspot.com/2013/05/watch-for-grape-leaves-disappearing.html http://xtremehorticulture.blogspot.com/2013/05/update-on-grape-leaf-skeletonizer-from.html http://xtremehorticulture.blogspot.com/2012/06/i-feel-really-bad-for-sue-and-her.html