14 BULLETIN 1262, U. S. DEPARTMENT OF AGRICULTURE. 
hours followed by a vacuum of one hour was necessary in order to 
sterilize to the center the 8-inch test pieces. 
AIR-SEASONING EXPERIMENTS. 
In the first air-seasoning experiments infected planks 2 by 10 
inches and 4 feet long cut from spruce (Picea canadensis) pulp 
logs were used. These planks contained typical and incipient 
stages of the decays produced by Lenzites sepiaria, Trametes carnea, 
Polyporus anceps, Trametes pini, Polystictus abietinus, and /omes 
pinicola. 
On July 28, 1920, 21 planks representative of the above material 
were stacked in the yard of the Forest Products Laboratory. The 
open method of stacking was used, and the layers of planks were 
separated by half-inch stickers. Adjacent to this pile another pile 
containing 33 planks was constructed. In this case the planks were 
closely piled one on top of the other. A third set of 39 planks of 
the same material was stacked open piled, while a fourth set of 
28 planks was stacked close piled in a well-inclosed shed. 
On June 11, 1921, records were taken concerning the number and 
species of fungous sporophores developed upon the planks since 
the piles were constructed. The open pile in the yard showed a total 
of 41 sporophores, of which 35 were Lenzites sepiaria and 6 were 
Trametes carnea. 'There were 23 sporophores on the planks in the 
close-piled set, and of these 13 were of Lenzites sepiaria, 2 were 
Trametes carnea, 6 Polystictus abietinus, and 2 Polyporus an- 
ceps. Most of these sporophores were of small size, but capable of 
producing spores. Many of the smaller of these dried out per- 
ceptibly during the warm, dry weather, but revived again during 
the prolonged rainy periods. Most of the sporophores appeared 
during the spring months. It is interesting that the largest number 
of sporophores were found upon the open pile and that of these 
over 85 per cent were of Lenzittes sepiaria, a fungus which thrives 
under comparatively dry conditions. In the closed pile only 56 
per cent of the total sporophores were of Lenzites sepiaria, and 
three other species were represented, in contrast to two species in 
the open pile. 
Cultures made from test blocks cut from the planks stored in the’ 
two piles in the shed showed that the fungi within the wood were 
still alive, although there were no indications that the decays had 
progressed within the planks. No sporophores had developed on 
any of these planks. 
On April 25, 1922, notes were again taken on the sporophore crop 
appearing upon the planks stacked in the yard. On the planks in 
the open pile a total of 61 sporophores were noted. Some of these 
were resupinate in character, and a few were buttons, or rudimentary 
fruit bodies. Of this total, 50 (or about 82 per cent) were Lenzztes 
sepuaria, 7 Trametes carnea, 2 Polyporus anceps, and 2 Stereum sp. 
On the closed pile were found 69 sporophores with about 10 buttons. 
Of this total, 42 (or about 61 per cent) were Lenzites sepiaria, 13 
were Z'rametes carnea with 10 buttons, 7 were Polyporus anceps, 5 
Polystictus abietinus, and 2 P. versicolor. 
A comparison of the closed pie with the open pile indicates that. 
the closed pile is more favorable to sporophore production and pre- 
