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SOME FUNGI IN WOOD.
By FRANK W. JANE, B.Sc., Ph.D.. F.L.S.
IN a Field Club, studies of the Fungi are chiefly systematic,
and our periodical fungus forays are devoted mainly to the
collection and identification of the sporophores of the larger
fungi, although the habitat of the species found may also arouse
interest. In the present paper it is proposed to direct attention
to wood, alive or dead, as a habitat of fungi, and to consider
those species, mostly larger Hymenomycetes, which are to be
found there. This will involve a study of the fungus as a whole;
the vegetative part, the mycelium, will claim most attention,
while the sporophores—all important to the systematist—will
be of minor interest.
Wood consists principally of two substances, cellulose and
lignin, and these, especially the latter, are remarkably resistant
materials. In nature their decay is brought about mainly by
certain fungi, and, possibly to a lesser degree, by bacteria: a
few animals, like some insect larvae, also possess the power of
breaking down these substances, but in some instances it
has been shown that they are able to do so with the assistance
of micro-organisms—Protozoa, bacteria and yeast-like fungi—
which inhabit their gut, and which contain enzymes enabling
them to break down cellulose [35]. The fungi, however, are, in
the main, the agents through which the substances in wood are
returned to the soil and air. This process of decay may be a
fairly rapid one; Waksman [33] records that certain Hymeno-
mycetes causing brown rot brought about a loss of from 10-50% of
the total material in 6-10 months, and Jay [21] found that one
Ash block infected with Polystictus versicolor lost 80% of its
dry weight in four months.
As wood destroyers the Basidiomycetes are an easy first,
although some Ascomycetes fulfil the same role ; some other
members of the latter group are found in wood, although they
do not bring about its decay. Among the Phyeomycetes certain
moulds may appear on sawn timber, although they likewise do
not destroy the wood.
At no time is wood immune from the ravages of fungi,
unless it has been treated in some way or is stored in some place
which protects it from attack. Many fungi attack the living