Cenangium – Dieback of pines-Cenangium ferruginosum
Symptoms / species
Impact / measures
Dieback of shoots, twigs, and parts of the crown; needles turn yellow to reddish-brown; Cenangium may affect pines of all ages; in late stages needles bleached but remaining attached to the the dead twigs for a long time; small, blackish, flat fruiting bodies exposing dull yellow discs (only when moist!), emerging usually in masses from the dead bark.
Affected tree species
Cenangium ferruginosum is often associated with dieback of crown parts of Pinus sylvestris and Pinus nigra, but the predisposing factors are not totally clear: drought stress and frost seem to be triggering factors.
Curative measures Solitary trees in urban areas should be sufficiently supplied with water. In forest stands of pines a careful thinning can increase vitality of healthy or only slightly infested trees and prevent secondary invaders (hygienic aspect).