hi.. welcome

its hard to go very far.. w/o some pix ...

all dead wood should be removed ... it aids in the healing process .... do you know how to prune properly ??? .. i would not define such as 'hacking' it off.. lol ...

and a bunch of other random thoughts...

new construction??? ... that can damage trees..

i dont understand how big these trees are ...well established larger trees should be rather free range..rather than need watering..

and you said: short number of frost free days

which makes me think you are at high elevation.. which you dont mention ... whats the closest large city..

and.. what are the odds that this is frost/freeze damage?? .. on the damaged leaves.. not the dead stuff ...

how about some pix.. so we can be more precise with our help ...

also.. you might want to talk with your county extension office..

ken

Do they look markedly worse than other cottonwoods in the area? I do not want you beating yourself up needlessly.

I am picturing the drive up Mt Charleston right now as your location.

That is not the easiest environment for trees.

I do know how to properly trim trees - sorry for the poor choice in words! :) The trees who have, for example, the top 2/3 dead require more than just pruning with nippers but rather sawing off - thus "hacking" which does sound totally brutal. haha

I am outside of Reno. In a rough year we get maybe 90 frost free days. Long sunny days, but cold nights! At least, as far as the plants are concerned.

These trees are maybe 6-8 years old. 12-15 feet tall.

I will take pictures and update tomorrow! Thanks for feedback and hope to hear from you once I add some images!

This post was edited by prairieway on Thu, May 30, 13 at 22:24

Here is a picture of some of the wilted leaves.

This picture is the same tree, just all of it.

Lastly, this is a picture of many of the trees. All of these have wilted leaves on at least part of the tree.

from what I understand cottonwoods in that part of the country typically grow in riparian habitats...not in the middle of a desert.....you might want to start all over.....mesquite is a possible alternative as are pinyon pine and joshua tree...they are much more tolerant than cottonwood of very dry conditions

Cottonwoods like water and your site doesn't look like it gets much. If you have ground water, the trees should be of a size to have found the groundwater and do OK even without surface water.

In the pictures, the trees look a little like they aren't getting enough water. However, it also looks like you have a drip line to water them. Another possibility is that they are getting salted out--either from the water supply, or it is limited enough that salts are concentrating where you are watering. If the trees can't get their roots to groundwater, I don't know that they will survive well long term.

I average about 7 inches of rain a year. Cottonwoods will seed in low spots in the badlands where water collects, but usually get around 10-15 feet tall, then overstrip the water supply and will die.

Don't mean to be gloomy, but without a good water supply either above or below ground, these trees won't have much of a future.

Okay - loads of information to consider. Thank you very much!

Thoughts so far--
I am, obviously, on sand and in the desert. But, aside from some very ambitious junipers there are no native trees for miles. With the exception of a few small ponds - all of these are lined in cottonwoods that are 150 feet tall, at least. They do love their water - and with water, can grow well here.

When you drive around rural outskirts of Reno you will see a lot of cottonwoods planted around peoples homes and animal structures. Also russian olives, many pine varieties, etc. They're easy to come by, not too expensive, quick growing, and provide what we so desperately need out here without other houses and trees to assist us - shade and wind protection! Of course, all trees would do this to some degree, but we get back to that "bordering on invasive" criteria. I also have a fruitless cherry tree on my property. What a waste that is! Expensive, short lived, disease and pest ridden. Ugh! So, I think, when weighing the options, I still want to work to keep these trees alive.

I also have 20 bare root firs and spruces as well as some oaks I plan to use to replace the trees on the drip line that are completely gone.

I suspect the group of trees pictured has found some source of water. It may not be enough, it may be salty, etc. But there are two lines of cottonwoods - One along the North side and one along the West - and both are nearly all dead. Considering all these trees received no care for a few years some of them must have hit water to still be alive.

I am trying to repair the drip system and make sure all the living trees get water :) It's tough! The person who laid it out wrapped it here, there, and everywhere. Some trees have 2-3 drips, some have none. Some drips work, some don't. So, guess I know what I am doing with my weekend!

Try your state Extension office for the leaf damage. Otherwise, it looks like you are not mulching - even in favorable climates this typically improves results markedly. And as already mentioned it would help a lot to choose trees adapted to the conditions you have instead of those you have been trying. At the moment you are trying to grow wetland trees in a desert, away from a stream or pond - an extreme mismatch between type of tree and type of site. To provide the right environment for moisture-loving trees in an arid climate you really need to be watering the entire site, as in sprinklers pouring water onto lush lawns, like they have at the Yakima Area Arboretum. Drip systems are not going to provide a large area of moist soil and a humid atmosphere.

Here is a link that might be useful: Yakima Area Arboretum

This post was edited by bboy on Sat, Jun 1, 13 at 15:40