Thus, housing developments in old cotton and alfalfa fields with a history of the disease can be disastrous for urban landscapers. The fungus is only active in summer months when air and soil temperatures are high. Infected roots rot and cannot transport water to the above-ground portion of the plant. Symptoms on above-ground plant parts resemble water stress. The first evidence of disease is slight yellowing of the leaves.
Leaves quickly turn to a bronze color and begin to wilt.
Permanent wilting of the branches can occur very rapidly, as little as two weeks from the first expression of disease. In some cases, the tree wilts so quickly that the leaves hardly change color, though they will become dry and brittle. A reddish lesion around the crown of the plant may develop on trees killed by the fungus. Evidence of P. omnivorum can also be found on or near infected trees. These strands look like threads and are visible with a good hand lens.