continental Europe and North America. C. pinicola has
been isolated from Scots pine and Corsican pine, in Great
Britain. C. douglassi is a common saprophyte found on
Douglas ¢r lumber in western North America [5]. These
three species colonize and stain the butts of wind blown
trees and broken roots or freshly cut logs or lumber [6]. C.
resinifera is found on Picea and Pinus species of continental
Europe and North America. In addition to saprobic
growth, this species has also been described as a weak
pathogen, growing rapidly from wound sites in living Norway
spruce. C. coerulescens, C. pinicola, C. douglassi and
C. resinifera are all thought to have non-speci¢c relationships
with bark beetles and other insect vectors, sporulate
readily in culture, and produce a strong aromatic aroma,
possibly to attract their vectors [3,6].
Another three species of Ceratocystis form close symbiotic
relationships with bark beetles. In association with
beetle attack these fungi are pathogenic to healthy trees.
The fungi sporulate scarcely in culture and do not produce
a fruity odor. C. ru¢penni, found in western North America,
is vectored by the North American spruce beetle Dendroctonus
ru¢pennis and is a pathogen of Engelmann and
white spruces [7]. C. polonica is found across Eurasia and
Japan on Picea species and is vectored by Ips typographus.
It is best known in Norway where it is an aggressive