68 
BULLETIN 934, U. S. DEPARTMENT OF AGRICULTURE. 
Table IX. — Results of the examination of damping-off foci in coniferous seed 
beds for Pythium dcbaryaman, Corticium vagum, and Fusarium spp. — Con. 
Beds treated with 
formaldehyde. 
Beds treated with 
copper sulphate. 
jBeds treated with 
zinc chlorid. 
All treated beds. 
Grouping. 
d 
03 
y, 
'o 
o 
Number 
showing — 
"6 
1 
03 
X 
a) 
'3 
o 
Number 
showing — 
■8 
1 
o3 
X 
<D 
'3 
O 
Number 
showing — 
T3 
a 
03 
X 
<s 
"o 
o 
Ph 
5 
Number 
showing — 
a 
2 
3 
o 
O 
03 
m 
g" 
i 
_3 
o 
Q 
a 
o3 
Ah 
d 
o 
O 
a 
03 
d 
2 
Ph 
*5 
a 
'3 
o 
O 

a 
03 
By locality: 
? 
Garden City, Kans. — 
Garden City Nurseries. . . 
6 

6 
3 
1 


l 
3 
1 

3 
52 
31 
175 
1 
14 
11 
67 

8 
2 
3 

23 
14 
34 
20 
1 
24 
6 
3 

5 
8 


5 
11? 
Cass Lake, Minn 

East Tawas, Mich. — 
1 
32 
7 
1 
20 
2 

13 


East Tawas Nurseries. . . 
8 
5 
4 

6 
5 
3 
3 
5 
3 

2 
7 
3 
Total: 
48 25 
100 52 
11 
23 
4 
50 
7 
18 
27 
56 


27 
68 
13 
100 
5 
100 
8 
100 
8 
62 
4 
80 
4 
50 
3 
23 
2 
40 
1 
13 
9 
69 
2 
40 
7 
88 
16 
100 
5 
100 
11 
100 
4 
25 
3 
60 
1 
9 






10 
63 
2 
40 
8 
73 
304 
100 
34 
100 
270 
100 
120 
39 
18 
53 
102 
38 
20 
14 
41 
12 
4 
161 
53 
By diagnostic methods: 
Direct examination- 
8 
100 
40 
100 
5 
63 
20 
50 
8 
?4 
Planted- plate cultures — 
1 51 
Percentage 
57 
The data on the different nurseries do not allow any generalizing 
on the basis of locality except to say that all of the fungi seem quite 
generally distributed in the Lake States and Great Plains region. 
In general, it appears that the Fusaria as a group are more common 
than either of the other fungi ; as they grow more slowly than either 
the Pythium or the Corticium, they were probably rather more 
common relatively than even the plate-culture method indicated. 
It also appears that the Pythium occurred in more foci than the 
Corticium in the beds examined. Further culture work, perhaps 
by the method of dilution plates of fragments of lesions, seems de- 
sirable, especially in the East and the Northwest, regions in which 
there are large coniferous nurseries and in which nothing like a 
parasite census has been attempted. Observations on the type of 
focus occurring in most of the nurseries in the Eocky Mountains 
leads the writer to believe that Corticium will be found especially 
important there. 
While the data on the fungi in foci in disinfected beds are insuffi- 
cient to serve as a basis for much in the way of conclusions for any 
individual treatment, they in general agree with the assumption, 
which knowledge of the fungi would favor, that Corticium is the 
