Willows - turning black/brown

[Uncle Leo]

Ok, now the willows. I have three. Again, hard clay soil, if that makes a difference. All three are pretty young. First two were purchased and planted in September 2006, the third one in October 2006 from a different local nusery. They are approximately 15-20 feet from the centerline of a drainage ditch, so lack of water isn't a problem, but there is new home construction going on upstream, so I don't know if maybe some chemical is absorbing into the soil that may be affecting these willows and maybe even the red oak I mention in another thread.

The first two are turning black from near the ground, and appear to be dying. They are, however, sprouting at the base. Does this mean they're salvagable? Toast? I should also add that they all had some foliage at the top in the beginning of spring, but not much, and now it is all gone. Also, the tree supports were not put on until May/June, so I wonder if maybe wind damage might have caused it.

The third one appears healthier, but is still discoloring.

Tree #1:

Tree #2:

Tree #3:

 

[Uncle Leo]

Anybody? I did an exhaustive search and found that most similar problems with willows get few, if any, responses. Does that mean there's nothing that can be done?

I'm presuming that since the base is spouting new branches that they are not completely dead, but I'd like to know if it's a fait accompli, or if they can be saved?

Will I end up cutting most of the tree at the base and letting the new sprouts grow?