Sulfur Fungus Rot
From Bugwoodwiki
|
Contents |
Importance
The sulfur fungus causes one of the most important rot diseases of ashes and many other hardwoods in the Eastern and Southern United States.
Identifying the Disease
A reddish-brown, cubical rot of the heartwood may develop in the roots, butt, or upper stem of the tree. The outward growth of the fungus from decaying heartwood may kill zones of vascular cambium and sapwood to form elongated cankers appearing as depressions in the bark.
Identifying the Fungus
The fungus annually produces bright-yellow to orange, shelflike basidiocarps, 20 to 60 cm wide, during the summer and autumn on living trees in advanced stages of decay. These fruiting bodies often develop in overlapping clusters from stem cankers and persist throughout the winter in the South. Their presence usually indicates extensive decay of the heartwood.
Biology
Fruiting bodies release spores during wet, winter months in the South. Basidiospores germinate and produce mycelia that infect trees through dead branch stubs and wounds of trunks or occasionally through roots. The white to pale-yellow mycelium develops an extensive rot column for many years before fruiting bodies produced.
Control
Bark wounds in forest stands should be avoided, and protuberant dead branch stubs should be removed from high-valued trees in urban areas to accelerate formation of callus over branch stub wounds.
