Invasive species may potentially affect Elm trees in Virginia. The Zigzag Elm Sawfly is new to our area. I'm not sure if this a tree service in Winchester, VA issue. It should definetly be reported. If anyone spots this highly noticeable pattern in your Elm tree leaves call the VA department of forestry. Side note it kinda looks cool. Please call Old Town Tree for any tree pruning, tree removal or stump grinding needs.