Something snipping branch tips off elm tree
I have a mature elm in my front yard and for the first time ever the ground under it is littered with a blanket of snipped off branch tips, mostly little twigs 3-4 inches long at best about 5 leaflets from the tip. My neighbor's tree is the same. Have had this tree over 15 years and have never seen this before. I split open one twig to see if there were any obvious larvae inside and there were not. Any idea what is causing this and what if anything I could treat it with? Thanks.
Anne Arundel County Maryland
Both the twig girdler and the twig pruner (insects) will snip twigs off elms. However, this doesn't usually occur until late in summer (August-September).
Twig girdlers make a "beaver cut" when they cut off the twig. Both cut ends come to a point, looking just like a beaver cuts a tree. A mature insect does the cutting.
Twig pruners, on the other hand, make a concave cut and it is done by the larvae. So, when cut lengthwise you should be able to locate a mature larvae.
In both species, the adults are attracted to light (at night.) So, turning off outside light may take care of it. (Light attracts a number of undesirable insect pests.)
Also, there is not insecticide labeled to control them anyway. So, the best control is to rake up the fallen twigs and destroy them. They are not a danger to mature trees, but more of an occasional nuisance.
On the other hand, a squirrel will occasionally get it into its head to snip off branch tips. Whether looking for water or just a young squirrel who doesn't know any better, we don't know. But it is not unusual for them to clip off quite a number of twigs. This is usually temporary.
Thanks. Likely its the pruner insect then, these have a concave cut. Good to know it won't drop a mature tree. The tree is near a street light so that might be the source of the attraction then. Appreciate the answer.