Vance
I know you have been growing many years, and have tons of experience with pines, but have you considered that the problem with white pines may be summer high pot temperatures? I had similar experiences with JWP until I stumbled upon the fact that high soil temperatures in summer due to solar pot heating 'cooks' the roots. These pines seem to be inordinately susceptible to this phenomenon. Growing them under 40% shade cloth has made an almost miraculous difference in the survival rate, eventhough the shade cloth doesn't change the ambient temperature at all.
I know of at least one other grower, in the South where it is very difficult to grow them, that has had the same experience. He shades his pots with styrafoam and foil.
Just a thought. For years, I blamed my failures on fungal problems as well. I am sure that this species is indeed troublesome with regard to root fungal problems, but I am also sure that high soil temperatures are also an issue.
Brent
EvergreenGardenworks.com
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