Yeasts and yeast-like fungi in stored timber

Abstract

A microbiological study of four series of wood samples taken from three areas (heartwood, sapwood and bark) of six species of timber logs (American basswood, black cherry, black locust, red oak, soft maple, and white poplar) during the summer, fall, winter and spring of 1987–1988 has previously been reported. The samples were analyzed for aerobic bacteria. Gram-negative bacteria, fungi and bacterial endotoxin. The present paper focuses on the yeasts and yeast-like fungi (e.g. Aureobasidium pullulans) isolated from these samples. The predominant species varied with the season, tree, and location. Pichia (Hansenula) sp. predominated, particularly in the August samples and especially from the sapwood of basswood, locust and cherry. Candida sake and other members of group 7 of the genus Candida were especially common in the samples taken in May from the sapwood and heartwood of maple and oak logs. Cryptococcus laurentii and Rh. glutinis were the predominant members of Cryptococcus and Rhodotorula, respectively, isolated from these samples.