746 
Journal of Agricultural Research 
Vol. XXIV, No. 9 
from the protected bed developed into normal growing shoots, while those 
from the unprotected bed remained in a dormant condition, apparently 
due to injury by these fungi. 
Table IV and Plate 3 show the root, top, and terminal bud develop¬ 
ment of Douglas fir seedlings grown three years in protected and unpro¬ 
tected seed beds. The trees from the unprotected bed had heavier 
roots and tops and a greater stem diameter. This is probably due to 
the fact that the stand of seedlings in the unprotected bed is much more 
open than in the protected bed, and consequently each plant has more 
growing space in which to develop. At the same time none but the 
largest and most vigorous seedlings survived in the unprotected bed. 
On the other hand, the roots from the unprotected bed were heavier in 
proportion to the weight of the plant, the tops being correspondingly 
less. This is probably attributable to the fungous injury to the tops, 
which was unfavorable to their development and which was much less 
pronounced in the protected beds. 
Table IV .—Rooty topy and terminal hwi development 
Bed. 
Average 
length 
of tops. 
Average 
length 
of roots. 
Average 
weight 
of tops. 
Average 
weight 
of roots. 
Ratio erf 
weight 
of root 
to 
weight 
of entire 
plant. 
Average 
diameter 
of stem 
at root 
collar. 
Average 
length 
terminal 
bud. 
Average 
width 
(rf 
terminal 
bud. 
Inches. 
Inches. 
Gm. ■ 
Gm. 
Per cent. 
Inches. 
Inches. 
Inches. 
Protected seedlinss 
(Bed 14). 
6.03 
11.43 
1.62 
0.46 
32 . 1 
0.08 
0 .34 
0. II 
Unprotected seed¬ 
lings (Bed 12). 
5 - 11 
10.68 
X. 78 
• 75 
29.6 
. 10 
.18 
.09 
The examination of field plantations revealed considerable fungous 
injury during the winter of 1919-1920, especially among jack pine, 
Engelmann spruce and Norway spruce. The jack pine were practically 
all dead and ti^e few living trees so severely injured that ultimate recovery 
was impossible. With Norway spruce and Engelmann spruce, the 
greatest injury from these fungi occurred on soils rich in organic matter, 
the surface of which was covered with considerable plant litter. The 
underplanting of aspen {Populus tremuloides) stands with Engelmann 
spruce, Norway spruce, and Douglas fir has been accompanied by notable 
losses on areas on which the ground was covered with a deep layer of 
aspen leaves. The heaviest losses occur where the plants are bent over 
into intimate contact with the soil and litter which is the breeding ground 
of these weakly parasitic snow-molding fungi. Serious loss by molding 
under the snow can be prevented in spring plantings by removing the 
accumulation of leaf litter from an area of one or two square feet, in the 
center of which the hole for the tree is dug and also by the use of large 
vigorous planting stock, which will stand erect during leaf fall and 
through the wet snows of the early winter and in this way hold its leader 
out of the zone of greatest danger. 
CONCLUSIONS 
The snow-molding fungi have caused a greater loss of coniferous nurs¬ 
ery stock at the Cottonwood Nursery than any other form of injury 
or disease. 
