Jahniella bohemica

Abstract

Abstract This note continues the “Cannabis Clinic” series, presenting diseases and pests of hemp, featuring colour illustrations of signs and symptoms. The fungus Jahniella bohemica damages hemp stalks in Europe. For 125 years this fungus has been confused with Leptosphaeria acuta, a fungus that infests nettle stalks. The morphology of J. bohemica is described in detail, compared to other Jahniella species, and also compared to L. acuta. The nomenclature of L. acuta is revised.