INTERNAL SPREAD OF FUNGI INOCULATED

The white-rotting basidiomycetes Exidia glandulosa, Peniophora quercina, Phellinus ferreus, Schizopora paradoxa, Stereum gausapatum and Vuilleminia comedenswere inoculated into attached living branches of oak (Quercus robur). Patterns of establishment and spread varied in relation to species, time of inoculation and location with respect to branch order and proximity of experimental girdles. Peniophora quercina, Stereum gausapatum and V. comedens readily formed localized decay columns within 6 months, but apparently failed to extend further subsequently. The other fungi either failed to establish, or spread only for limited distances, E. glandulosa preferentially colonizing bark. Longitudinal spread was often markedly facilitated within the vicinity of a girdle, although radial and tangential spread were restricted. In several instances, individuals of Peniophora quercina, Stereum gausapatum and V. comedens became established naturally within the branches. Such individuals were invariably somatically incompatible with those inoculated, and further contrasted with the latter in giving rise to columns of considerable longitudinal and radial extent.