Sirococcus clavigignenti-juglandacearum is responsible for dieback and decline of butternut. It was first described in 1923, but reports of the malady go back to the turn of the century. The casual organism was at first thought to be Melanconis juglandis, a weak pathogen found throughout the butternut range. However, Sirococcus clavigignenti-juglandacearum has recently been found to produce a canker that leads to the decline; M. juglandis is secondary.
|Family: Incertae sedis|
|Subject: Sirococcus clavigignenti-juglandacearum N. B. Nair, Kostichka & Kuntz|