Ea. Burrill et al., Effects of defoliation and cutting in eastern oak forests on Armillaria spp. and a competitor, Megacollybia platyphylla, CAN J FORES, 29(3), 1999, pp. 347-355
Citations number
41
Categorie Soggetti
Plant Sciences
Journal title
CANADIAN JOURNAL OF FOREST RESEARCH-REVUE CANADIENNE DE RECHERCHE FORESTIERE
Gypsy moth (Lymantria dispar L.) and Armillaria root rot interact to cause
extensive mortality in eastern oak forests. Defoliation by gypsy moth weake
ns trees and increases their susceptibility to Armillaria root rot. Partial
cutting prior to defoliation has been proposed as a management technique b
ecause it may increase tree vigor and the ability to withstand defoliation
stress. However, cutting could also increase inoculum potential of Armillar
ia by providing a resource, the residual stumps. Megacollybia platyphylla (
Pers.:Fr.) Kotl. & Pout. is a native, cord-forming, saprobic fungus that ma
y compete with Armillaria for resources such as stumps, snags and debris. A
factorial treatment design with three levels of cutting and three levels o
f defoliation was used to examine the effects of cutting and defoliation on
the two fungi. Among uncut stands, defoliated stands had significantly gre
ater colonization of resource units by Armillaria than nondefoliated stands
. However, stands that were cut prior to defoliation had significantly less
Armillaria colonization and significantly more M. platyphylla colonization
than those that were not cut. Armillaria colonized snags better than stump
s and colonized least well in debris, where M. platyphylla showed its best
colonizing performance. The data suggest that cutting mitigates the effects
of defoliation on colonization by Armillaria and are consistent with the h
ypothesis that M. platyphylla plays a role in such mitigation.