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A number of ophiostomatoid fungi were isolated from the spruce-infesting bark beetle, Ips perturbatus and its galleries collected from felled spruce trees and logs in northern BC and the Yukon Territory. Isolates were identified to species using morphological characteristics, nuclear ribosomal DNA and partial beta-tubulin gene sequences. Thirteen morphological and phylogenetic species were identified among the isolates. Leptographium fruticetum, Leptographium abietinum, Ophiostoma bicolor, Ophiostoma manitobense, O. piceaperdum, and eight undescribed species of the genus Ophiostoma and the anamorph genera Leptographium, Hyalorhinocladiella, Ambrosiella and Graphium. A number of these species, i.e. L. fruticetum, Hyalorhinocladiella sp. 2, O. bicolor and O. manitobense, were isolated repeatedly from I. perturbatus, while others, i.e. Graphium sp. 1 and O. piceaperdum, seemed to be sporadic associates. Among all the isolates, L. fruticetum had the highest relative dominance in this survey. A high frequency of occurrence of this species with the beetle may indicate a specific relationship between the two partners.

An undescribed Leptographium species was isolated from the spruce-infesting bark beetle Ips perturbatus collected from felled spruce trees and logs in northern British Columbia and Yukon Territory. Morphologically, this fungus is similar to L. abietinum and L. hughesii but differed in a number of characteristics (e.g. the arrangement of its conidiophores). The fungus grew optimally at 25 C on 2% malt-extract agar and showed a high level of tolerance to cycloheximide. Comparison of rDNA and beta-tubulin gene sequences also confirmed that this Leptographium species represents an undescribed taxon. Thus we described it as a new species, Leptographium fruticetum sp. nov.

The work reported here investigated the fungal community inhabiting western redcedar fence material with a focus on species colonizing wood below the surface, of which little is known. From seven pieces of fence material, twenty-three different fungal species were isolated and characterized using both traditional morphology and molecular identification methods. The species identified included thirteen ascomycetous and ten basidiomycetous fungi. Isolates were tested for their resistance to beta-thujaplicin - one of the principle fungicidal agents of western redcedar heartwood extractives. Generally, ascomycetous fungi exhibited greater resistance to beta-thujaplicin than basidiomycetous fungi. Interestingly, three ascomycetous and two basidiomycetous species frequently isolated had high tolerance to this compound. These species could be candidate 'pioneer' species that invade and detoxify western redcedar extractives, paving the way for colonization by decay fungi.