White powdery growth on leaf surfaces may become heavy late in the season, especially on tender leaves of sprouts. Spots are very thick, jet black, discrete and about one-fourth inch in diameter. It looks like a drop of tar on the leaf. Rake up an burn dead leaves, as the fungus overwinters on them. Spray early in April with a fungicide.
Most willow species are highly susceptible.
Plants suddenly wilt and die, leaves usually hanging on the plant. Roots will be decayed with the bark peeling off very easily. Wood decay fungi usually enter the tree through wounds. Most fungi grow rather slowly showing no evidence of being present until extensive areas are rotted. Most will first invade the non-functional heartwood.