60 BULLETIN 544, U. S. DEPARTMENT OF AGRICULTURE. 
material source of danger, provided they are brought into contact 
with the soil and rapid decay thus induced. Spruce branch wood, 
however, on account of its resinous character, is particularly inflam- 
mable and resistant to decay, and constitutes a fire menace for several 
3~ears when unlopped and from 7 to 10 years when lopped. In the 
forests where spruce is the predominating species, and particularly 
in the dense second-growth woods, an enormous quantity of such 
branch wood litters the cutting area. The ground is likewise covered 
with a dense mantle several inches in depth of dry needle litter, small 
twigs, and old cones. All this debris when exposed to the action of 
sun and wind with the cutting off of the forest cover, is quickly dried 
out and remains for several years an acute fire menace. The excessive 
branch- wood litter following lumbering and the deep humus cover 
also greatly hinder spruce reproduction on such areas and help the 
hardwoods and balsam to take possession through their superior 
ability to force their way to mineral soil. 
When the selection system or other partial clearance cuttings are 
used or where the present age of spruce to be cut is not great, and where 
also a subsequent cut is dependent upon the maturing of seedlings or 
small trees which are on the ground at the time of the first cutting, 
the disposal of brush by burning is ordinarily not necessary unless the 
cut-over area is one on which there is special danger of fire getting a 
start. 
BRANCH WOOD POPPED AND SCATTERED OR PILED. 
If only a little brush is produced and the fire danger is remote, the 
brush from the carefully lopped tops may be scattered about over 
the ground, thus hastening its decay. This method has given satis- 
faction where it has been tried in certain instances in the Adirondacks 
at a cost of from 15 to 25 cents per thousand board feet of lumber cut. 
Where more brush is produced than can safely be disposed of in this 
manner, the tops should be lopped and the branch wood piled. This 
will bring the larger material in contact with the soil, thus hastening 
decay. The segregation of the more inflammable material in compact 
bodies will reduce to a minimum the hindrance to reproduction and 
will effect a corresponding reduction in the danger from a rapid spread 
of fire should one start on the area. 
BRUSH BURNED AS LOGGING PROCEEDS. 
Excessive amounts of brush such as arise from the clean cutting 
of dense pure stands should be disposed of by burning. The most 
economical means of doing this is to burn the brush as the logging 
progresses. This is feasible when the ground is covered with snow or 
is damp so as to prevent the spread of fire. Small fires are started 
near each cutting crew and as the trees are felled the branches are 
lopped by the swampers and thrown into the fire. As the cutting 
