406 AMERICAN JOURNAL OF BOTANY IVoI. io, 
Table i.— (Cont.) 
Temperature (degrees C.) 
1 
1 Days 
60 
70 
80 
90 
100 
105 
no 
Trametes camea , . 
1 
2 
+ 
+ 
+ + 
+ -- 
_ 
_ 
_ 
1 
+ 
+ 
+ + 
+ -- 
— 
— 
— 
if 
+ 
+ 
+ + 
— 
— 
— 
— 
2 
+ 
+ 
+ + -- 
— 
2§ 
+ 
+ 
+ + -- 
— 
3 
+ 
+ 
+ + -- 
4 
+ 
+ 
— 
6 
+ 
+ 
— 
7 
+ 
— 
8 
+ 
— 
9 
+ 
—. 
15 
+ 
Lentinus lepideus . 
1 
2 
+ 
+ 
+ + 
+ + - 
+ 
_ 
_ 
1 
+ 
+ 
+ + 
+ -- 
— 
■ — 
— 
+ 
+ 
+ + 
— 
— 
— 
— 
2 
+ 
+ 
+ 
— 
— 
2! 
+ 
+ 
+ 
— 
3 
+ 
+ 
+ 
4 
+ 
+ 
— 
5 
+ 
+ 
6 
+ 
+ 
7 
+ 
— 
8 
+ 
— 
9 
+ 
— 
15 
+ 
applicable. If some of the rarer fungi attacking coniferous woods are 
more resistant to heat than the resistant Lenzites trabea, these results and 
the discussion following do not apply. Just how far they would hold for 
hardwoods which are infested with different fungi can only be conjectured, 
although Lenzites trabea is common on hardwoods and L. sepiaria occa¬ 
sionally occurs on them. In the remainder of the paper, however, it is 
assumed that by far the greater part of the combat against structural- 
timber-destroying fungi is against species to which these results are appli¬ 
cable, i.e., the five considered here and others like Merulius which are less 
resistant to heat. In applying these results to kiln-drying, it is assumed 
that the effect upon i-inch stock would be about the same as upon the 
f-inch blocks used in the experiments. In processes in which the kilns are 
run at a fairly uniform temperature and humidity, the possible killing 
effect of the heat used may be determined from the curves presented (text 
fig. i). In the case of softwoods dried directly from the saw in a green 
condition with high temperatures, any mycelium should be killed, inasmuch 
as none of the fungi used, which are the commoner ones, could stand 12 
hours at 55 0 C. moist heat. In the case of hardwoods, the killing of wood- 
destroying mycelium would depend upon the combination of time and 
temperature (if not the species of fungus)—especially, perhaps, upon the 
