64 
BULLETIN 934, U. S. DEPARTMENT OF AGRICULTURE. 
Table VIII. — Results of inoculations with miscellaneous oomycetes on pines in 
autoclaved soil at the time of sowing — Continued. 
Num- 
ber of 
pots. 
Results. 
Experiment number, host, and inoculating fungus. 
Emerged. 
Damp- 
ing-off. 
Survival. 
No. 68, Pinus resinosa: 
Phytophthora sp.— 
Strain 358 
5 
5 
5 
5 
5 
5 
5 
5 
5 
5 
18 
3 
3 
2 
3 
3 
16 
3 
3 
3 
2 
2 
14 
Per 5-pot 
unit. 
104 
109 
98 
121 
122 
120 
96 
110 
94 
84 
104 
Per 3-pot 
unit. 
20 
62 
45 
37 
40 
35 
8 
13 
11 
29 
6 
9 
Per cent. 
7 
18 
5 

1 
9 
5 
6 
1 
2 

35 

7 

25 
5 
50 
8 

6 


Per 5-pot 
unit. 
97 
Strain 372 
89 
Strain 375 
93 
Pythium artotrogus (?), Michigan strain 
121 
Pythium artotrogus (?), Washington, D.C. — 
Strain 821 
121 
Strain 823 
109 
Strain 831 
91 
Strain 832 
103 
Strain 833 
93 
Undetermined Phycomycete 
82 
Controls 
104 
No. 72A, Pinus resinosa: 
Phytophthora sp.— 
Strain 372 
Per 3-pot 
unit. 
13 
Pythium artotrogus (?), Michigan strain 
62 
Pythium artotrogus (?), Washington, D.C— 
Strain 821 
42 
Strain 831 
37 
Strain 833 
30 
Controls. . 
33 
No. 72B, Pinus ponderosa: 
Phytophthora sp. . . 
4 
Pythium artotrogus (?), Michigan strain 
12 
Pythium artotrogus (?), Washington, D. C— 
Strain 821 
11 
Strain 831... . 
27 
Strain 833 
6 
Controls 
9 
OTHER FUNGI. 
Data on the possible relation between various other fungi and the 
damping-off of conifers have been already summarized by Hartley, 
Merrill, and Rhoads (68, p. 546-550). Pestalozzia funerea on the 
basis of the experiments of Spaulding (135), Botrytis cinerea on the 
basis of observation and very preliminary inoculations, and Tricho- 
derma honingi on cultural evidence only are all believed to be po- 
tential causes of damping-off, though not ordinarily important. Al- 
ternaria sp. is under a certain amount of suspicion on account of its 
frequent association with the damping-off of conifers, but it has 
never been used in experiments. Rhizopus nigricans (incorrectly re- 
ported as Mucor) , Trichothecium roseum, Rosellinia, sp. from nursery 
soil, Chaetomium sp. from maple roots, strains of Penicillium and 
Aspergillus, Phoma betae, and Phoma spp. are all reported to have 
been used in inoculations with negative results. 
Since the publication of the above summary a preliminary success- 
ful inoculation experiment with Botrytis cinerea on recently emerged 
Pseudotsuga taxifolia has been found briefly mentioned in an article 
by Tubeuf (140) on another disease. Further experiments with va- 
