|I have six 40-50 year old chinese elm trees, that are slowly dying. There are several small holes in the bark of 5 of the six trees. We also have horse corrals and other livestock pens on the property, where I have noticed a lot of grubs in the soil, espeically after we get rain, I first started noticing the grubs about 2 years ago. Can you please tell me what has caused the holes in the bark what I can do to save these trees?? I have already cut back the deadwood, and sealed the cuts with pruning sealer. Thanks for your help|
|Elm trees are susceptible to emerald ash borers and the holes you see on the trunks and branches of the tree are signs of borer infestation. These pests are extremely difficult to control, although with small trees it is possible to skewer the worms that are hiding inside the holes with a straightened out paperclip. I doubt that's something you'll be able to do with such large trees, though. The grubs you're finding in the soil are not the same grubs as are making homes in your elm trees. It might be worth your while to hire an arborist to come out and inspect your trees so you'll know just how extensive the damage is/will become. You might also contact your local cooperative extension office for their recommendations about treatment and control. Sometimes extension agents and/or trained Master Gardeners will make house calls. It won't hurt to ask. Contact Arizona State University Cooperative Extension, 4210 N Campbell Ave, Tucson - (520) 626-5161
Best wishes with your trees.