Infection cycle of Armillaria and host response

In the infection cycle of Armillaria spore dispersal is followed by colonization of stumps, which is not uncommon on the time‐scale of plantation forestry. After a period of exploitation, further suitable woody tissues nearby may be colonized by means of rhizomorphs or direct mycelial transfer. The cycle is illustrated by four species present in southern England, which vary in pathogenicity, capacity to invade tissues deelining in resistance, and ability to form rhizomorphs. Various host responses, such as production of oleoresin by conifers and secondary meristematic activity, are briefly discussed.