742 
Journal of Agricultural Research 
Vd. XXIV, Na 9 
the writer submitted diseased specimens to Dr. Carl Hartley, who 
reported that the organisms were evidently the same as those with which 
he had worked. 
For several years the practice of sowing black soil on the snow early in 
the spring to hasten its melting was followed by the nurserymen, but 
even with this practice the losses were still so heavy that the growing of 
Douglas fir on a large scale at the Cottonwood Nursery was discontinued 
in 1916. 
TabI/^ I .—Percentage of injury by snow-molding fungi in the several species and age 
classes, spring of igeo 
Species. 
Age class. 
Dead. 
Alive but 
injured. 
Per cent. 
Per cent. 
Picea engelmanni . 
i-^ 
31*3 
0 
2-0 
27.7 
0 
2-1 
9.9 
0 
3-2 
8 . I 
0 
Picea excelsa . 
2-0 
77.0 
0 
2-1 
63. 0 
22.3 
3-2 
59-3 
0 
Pseudotsuga taxifolia . 
I-O 
62. 9 
0 
2-0 
62. 7 
0 
Pinus ponderosa . 
I-O 
93-2 
6.8 
2-0 
52. 2 
44*7 
2-1 
15.2 
12.3 
Pinus ponderosa scopulorum . . 
I-O 
16. 8 
2-5 
2-0 
7,8 
3*4 
2-1 
3-5 
IS-8 
The extent of the injury by these fungi among the different species 
and age classes is shown in Tables I and II, which are based upon counts 
of from several hundred to as many as 2,400 seedlings in each age class. 
It is recognized that a small loss occurr^ during Sie summer seasons 
but it was*found to be negligible in comparison wi& the loss due to snow 
molding. Table I and Plate i show the much greater susceptibility of 
the exotic Nonvay spruce to the disease as compared with that of the 
native Engelmann spruce. Table I shows quite clearly that the younger 
age classes, i-o and 2-0, suffer by far the greatest loss and injury. 
Table II fails to bring out this relationship so clearly mainly because of 
the fact that a large part of the older age classes of stock had been aban¬ 
doned, receiving no water or care of any kind during the summer of 1920. 
This Mt the stock in a weakened condition and an easy prey for the 
fungi. For example, 3-3 Engelmann spruce shows' (not in Table II) 
41.5 per cent of dead and injured trees as compared with 3.4 per cent 
for the 3~2 stock and 7.1 per cent for the 3-1 stock. The first age class 
had been abandoned in 1920, while the latter two classes of stodk were 
watered and otherwise properly cared for during 1920. It should be 
noted, therefore, that among the older age classes, especially transplants, 
it is usually the weak or previously injur^ trees that are killed or severely 
injiured. It is not uncommon to fmd some of the leaves of vigorous 
transplants infected when the snow melts, but the development of the 
fimg^Js cheeked as soon as the trees are exposed to the sunlight, and 
complete recovery may follow. Jack pine {pinus banksiana), however, 
