22 
Journal of Agricultural Research 
Vol. XI, No. i 
the stark, dead forest of snags offers just sufficient protection from the 
sun’s heat and excessive evaporation to make of the forest floor an ideal 
germinating bed. The dormant seeds, bedded in the unbumed duff, 
are stirred to life and respond to the stimulus. Germination proceeds 
for each species in a manner peculiar to itself; the true firs crowd over 
90 per cent of their total germination into the first season after the 
removal of the forest; white pine reaches its highest figure during the 
third season; hemlock shows a similar tendency; and Douglas fir germi¬ 
nates probably less than half its seed during the first season. 
A few years after the fire the greening of the hills in the Columbia 
bum, with a mantle of reproduction, arrested the attention and aroused 
the wonder of those who had taken for granted that this was to be a 
“denuded” bum, because of its large extent and the thoroughness of 
the burning. The occupation of the bum by reproduction was not a 
gradual creeping out from the surrounding bodies of green timber, but 
a sudden taking possession of the entire area. In ordinary wind migra¬ 
tion 11 years (the age of this bum) would have sufficed for only the be¬ 
ginning of a process of reforestation that would take generations to com¬ 
plete. Yet within 5 years the duff-stored seed had clothed fully 80 per 
cent of the Columbia bum with a satisfactory tree cover. 
CUT-OVER AREAS: THE EFFECT UPON RESTOCKING OF BURNING 
SLASH AND OF LEAVING SLASH UNBURNED 
The conclusions reached with regard to the source of seed from which 
reproduction starts on bums have been corroborated by the study of 
cut-over lands about Puget Sound during 1915 and 1916. In the Douglas- 
fir region covered by this study the slash is left broadcast and almost 
invariably burned. Thus, a study of cut-over areas is only another step 
in the study of bums, and covers a fire which is more severe on the sur¬ 
face because of the debris left by logging operations. 
On one area cut over in 1914, burned in the spring of 1915, and left 
covered with blackened logs and ashes, cones of cedar and hemlock were 
found almost everywhere buried in the unbumed duff. The cones were 
papery and almost decayed, but they were still intact in shape and con¬ 
tained seeds with firm endosperm. Throughout this bum there were 
small islands which had escaped burning and which contained large 
numbers of cedar and Douglas-fir seedlings germinated in the fall of 1915. 
These islands of reproduction demonstrate the presence of seed over 
the area previous to the 1915 fire, and show that if the slash had not been 
burned the area would have been covered with a good stand of repro¬ 
duction of the same species as the original forest and in about the same 
proportion. 
Reproduction forming a satisfactory stand—that is, 300 or more seed¬ 
lings per acre—was not found more than 4 chains from green timber, 
and usually only 2 chains in localities where the stand depended entirely 
