Black Knot Fungus

By William T. Hathaway

Black Knot Fungus

In the realm of nature lore there are many of us who have an insatiable curiosity. While enjoying the various colors and forms found in the woodlands, there comes a time when an unsightly attraction may command our attention. This Black Knot Fungus or “smut fungus” was conspicuously infecting the lower branches of a Wild Black Cherry Tree (Prunus serotina).

In seeking information one finds that the black knot fungus Apiosporina morbosa (sym. Dibotryon morbosum) may spread its spores by wind and rain to twigs on the same tree and nearby trees. Fortunately, this fungus is not a common problem to the wild cherry trees in Pittsylvania County.

As an afterthought, it is interesting to note that the Wild Choke Cherry (Prunus virginiana) is rarely found in Pittsylvania County, but is common in the mountains; our common wild cherry tree is the Wild Black Cherry (Prunus serotina).