Q: A mesquite tree beside my driveway is getting new leaves, but I noticed a couple of dead branches among the greenery. They snapped off easily at a point where they appeared to have been neatly girdled. Does some kind of critter do that, and why?
A:Β Yes, the critter is commonly known as the mesquite twig girdler (Oncideres rhodostica). It is a long-horned beetle, about an inch long, that is native to our area and not considered to be a pest.
The female of the species does the girdling and then lays her eggs out beyond the girdle. The larvae feed on the nutritious cambium layer under the bark.
The nice way to think of this damage is as natureβs way of pruning your tree.
Peter L. Warren is the Forest Health Program Coordinator for the Arizona Department of Forestry and Fire Management. Questions, photos and videos may be emailed toΒ tucsongardensage@gmail.com
