Humphrey: Durability of American Woods 
89 
TABLE VI 
Durability of Heartwood after 12 Months’ Test 
[An asterisk (*) denotes that the blocks became too wet for a fair test.] 
Kind of Wood 
Flask 
Oven- Dry 
Weight (Grams) 
Loss 
Remarks 
No. 
Before 
Test 
After 
Test 
Grams 
Per 
Cent. 
Eastern hemlock 
18 
7-8S 
3-17 
4.68 
S9-6 
Friable when dry. 
Mountain hemlock .... 
18 
8.61 
308 
SS3 
64.2 
Friable when dry. 
Western hemlock 
IS 
7-94 
3-o8 
4.86 
61.2 
Friable when dry. 
Engelmann spruce 
IS 
7-23 
2.27 
4.96 
68.6 
Friable when dry. 
Sitka spruce 
IS 
4-33 
1.63 
2.70 
62.4 
Friable when dry. 
Red spruce 
IS 
7.07 
2.30 
4-77 
67-S 
Friable when dry. 
White spruce 
IS 
S.62 
1.70 
392 
69.8 
Friable when dry. 
Grand fir 
IS 
7. TO 
2.12 
4.98 
70.1 
Friable when dry. 
Noble fir 
IS 
7S3 
2.25 
S.28 
70.1 
Friable when dry. 
Douglas fir 
II 
7.43 
S-34 
2.09 
28.1* 
Seriously rotted at 
ends. 
European larch 
IS 
7.88 
4-SO 
338 
42.9 
Well rotted. 
Western yellow pine . . . 
18 
7.60 
3-3S 
4-2S 
SS-9 
Friable when dry. 
Lodgepole pine 
18 
6.93 
2.47 
4.46 
64.4 
Friable when dry. 
Longleaf pine 
12 
11,42 
S-S9 
S-83 
Si-i 
Friable when dry. 
Shortleaf pine 
II 
12.25 
9.72 
2.S3 
20.7 
Seriously rotted in 
summer wood. 
Table mountain pine. . . 
18 
10.22 
6.17 
4-OS 
39-6 
Friable when dry. 
Pitch pine 
18 
10.02 
8.93 
1.09 
10.9* 
Considerably rotted. 
Norway pine 
18 
8.00 
2.4s 
s-ss 
69.4 
Friable when dry. 
White pine 
18 
6.71 
6.12 
0.S9 
8.8 
Slightly rotted. 
Sugar pine 
18 
6.06 
2.SS 
3-Si 
S7-9 
Friable when dry. 
Western white pine. . . . 
18 
7.14 
4-8S 
2.29 
32.1* 
Well rotted at ends. 
White cedar 
12 
S-40 
S-ii 
0.29 
S-4* 
Slightly rotted at 
ends. 
Western red cedar 
II 
S-i6 
4.06 
1. 10 
21.3* 
Seriously rotted at 
ends. 
Port Orford cedar 
II 
7.81 
6.05 
1.76 
22.6* 
Seriously rotted at 
ends. 
California juniper 
12 
10.66 
10.31 
0.3s 
3-3 
Slightly affected. 
Western juniper 
II 
S-S8 
4-73 
0.8s 
IS-2* 
Seriously rotted ta 
one end. 
Bigtree 
II 
7.07 
4-S9 
2.48 
3S-I 
Seriously rotted. 
considered as having no special significance beyond the fact that 
little discrimination can be made between them or between the 
different species represented. 
For the six months’ period the average loss in the sapwood of 
21 species (exclusive of white cedar) was 48 per cent., while the 
average loss in the heartwood of hemlocks, spruces and firs was 
49.6 per cent. These figures show that decay progressed at the 
same rate during the second three months as during the first three 
(allowing one month after inoculation for the fungus to become 
uniformly distributed throughout the flasks). 
