Mark, I establish trees on many different types of soil here without the help of irrigation- and these are bearing age trees much more susceptible to drought stress in their first year of establishment than are your trees. I can't say these trees are never stressed by drought, but it has never killed them. I've never seen trees visibly stressed by lack of water under the conditions you describe, although I can't be sure of all the conditions there. I will way that I use about a 6' diameter mulched ring with around a 3-4" layer of woodchips at most sites. Your weed free rings are pretty stingy for unirrigated trees not yet fully established. We didn't establish the root stock of trees that are affected. 111 is fairly drought resistant, M7 less so and more dwarfing rootstock much less so. M26 on down often need irrigation- especially when young.

We will definitely look into the viburnum. Thank you, laceyvail. rhizo_1, thank you for responding. We sheared them from the time we planted them, twenty-five years ago - They actually are 20 - 25 feet tall and about 10 feet wide. We have had to use a bucket truck for the past 3 years to get the job done. Since we have to remove them, we would prefer something more manageable (height, width, pest-resilient, etc.) -

I, too, worry when someone is guessing about the dosage of a pesticide. It's dangerous for the applicator as well as for the environment. The responsible use of imidicloprid pesticides requires knowledge of the most effective timing as well as making certain that the dose will be correct. Another factor that worries me is that some insects are developing resistance to this class of pestides (neonicotinoids) . But the biggest headache is that these chemicals have proved to cause a population explosion of pests after the effects begin to wear away. This ends up causing increased problems....and more pesticides. I strongly advise that our original poster wait for several weeks to see if there are any positive results. By that time, the trees will be preparing for autumn. I also suggest that he/she call the toll free number found on every label to ask for advice. Know the identification of the pests and the measured circumference of each tree. Be honest with your particular dose. I'll bet that you get lots of help. I agree that the 'lint' insects are not whitefly but hackberry wooly aphids. You might not be observing or recognizing other pests, as well. Don't you think that it might be time for you to call on a professional? An ISA (International Society of Arboriculture) Certified arborist is required....not any 'tree guy '. One of the most effective control measures is horticultural oil applied in the winter. This treatment smothers the eggs of many pests, breaking the cycle. I doubt that any professional will spray acephate everywhere and Bt is useless on whitefly (or wooly aphids, for that matter).

Yes, very much in its infancy, this whole area. Some-I occasionally include myself in this group-talk about "novel ecosystems". Very basically, we're not going to get things back to 1850.....or 1750...or whatever benchmark year one would use to set a time when things weren't messed up like they are now. So what do we do? In the east, where hemlock has been devastated by the woolly adelgid, do we import Asian hemlock genetics to at least have a somewhat-similar tree in our forests? Or do we mass plant Norway spruce because that species is a proven performer here in N. America......and somewhat fills the same niche? I'm not proposing these ideas as subjects of debate here on the Trees forum, but rather, to get folks thinking about where we may be headed. As it is, here in Wisconsin, ash trees are ultra-common, and I fear most spaces now occupied by green and white ashes especially, will be filled with junk buckthorn and non--native honeysuckles. This truly seems inevitable. Throw in a state government that couldn't care less about such matters, and well.....it's looking bleak. +om