FOMES ANNOSUS 
29 
tree in this state. It will be noticed that the enclosed 
branches are not attacked, the mycelium preferring the 
easier task of destroying the softer tissues. 
Hartig says the mycelium does not pass up into the trunk 
of the Scotch pine, being kept back by the abundant resin 
present in the lower part of the stem in these trees. Its 
presence in a stem in the early stage of attack can only be 
demonstrated by microscopic examination, and is often 
present when least suspected. A large number of sections 
of trunks of young Austrian pine and Norway spruce were 
stacked against the inner wall of my wood-shed in March, 
1908. Each section was about a foot long, and all were 
placed in such a manner that only one end was exposed to 
the light. The trees when felled appeared to be quite 
healthy. No notice, however, was taken of their roots; they 
were felled by woodmen in the ordinary course of thinning 
out a plantation. Early in the following November it was 
observed that many of the sections had developed pileate 
sporophores, in all cases only upon the end exposed to the 
light. The appearance presented by one of them is shown 
in Plate XII., 4. 
There comes a time when an attacked tree shows external 
signs of disease, chiefly indicated by the foliage becoming 
pale, but many years may elapse before this takes place. 
A large and apparently very healthy am’ vigorous spruce 
growing within a few hundred yards of the Haslemere 
Museum was struck by lightning, and a large piece torn 
away from the side of the trunk. To the astonishment 
of all who saw it, this tree was completely hollow, and 
must have been attacked by the parasite many years pre¬ 
viously. 
A tree very quickly dies after the foliage has commenced 
to change colour, and examination always reveals a plentiful 
crop of sporophores on the roots. Plate XII., 6 shows an in¬ 
verted stump of a Scotch pine with numerous resupinate 
