8 BULLETIN 1493, U. S. DEPARTMENT OF AGRICULTURE 
It is a matter of common cbservation that many excellent stands 
of seedlings or saplings occur on lands logged off recently and on 
those cut over some time ago; and were all cut-over lands in this 
condition there would be no ‘‘reforestation problem” and no occa- 
sion for this discussion. However, on many other areas of equally 
favorable physical environment little or no reproduction is to be 
found. Wherever this occurs, adverse factors are present. ‘To under- 
stand what present-day practices are favorable and what are unfavor- 
able to the successful establishment of a new crop of timber, certain 
facts about Douglas fir and about its reproduction and protection 
must be known. These are discussed in the following pages, in so 
far as they bear on the measures necessary to Insure a new crop 
after logging. 
SEED PRODUCTION 
Seed is produced in abundance from the time the stands are about 
25 years old until they are decrepit. Bountiful seed crops are not 
annual, but occur perhaps two or three times per decade; about 
every third year practically no seed is borne. ‘There is considerable 
uniformity the region over in the heaviness of the seed crop. 
SEED DISSEMINATION 
Douglas fir seed (as well as that of its principal associates, cedar 
and hemlock) ripens in late August, the cones open, and much of 
the seed is released then. With damp weather the cones partially 
close, and when they open again on dry days more seed is released. 
In this way the dispersion of the seed is continued through the fall 
and early winter. An appreciable amount of good seed can be found 
in the cones in midwinter. 
The light-winged Douglas fir seed is borne away from the parent 
tree by the wind and is subject to the wind’s vagaries. The seed 
dispersed on still days naturally alights close by; in high winds it 
may fly far. The maximum distance at which seed trees can do 
effective seeding is not known; 1t depends, among other things, upon 
topography, the season, and the amount of seed dispersed. Crusted 
snow could easily increase the distance that winter-sown seed may 
be carried by wind. Birds and animals undoubtedly have a réle in 
disseminating some seed. The more abundant the source of seed, 
the greater the effective seeding distance. A single seed tree naturally 
will not seed effectively for as great a distance as a solid bank of 
timber. Beyond a quarter mile on level ground even a large mass of 
trees will probably not do effective seeding, and even up to that 
distance they may take several years to seed the ground thoroughly. 
Much freshly logged and burned iand is seeded up by adjacent 
uncut timber, which is often close enough to be effective until cut 
in the advancing logging operation. 
SEED STORAGE IN THE DUFF 
An acre of virgin forest during a favorable seed year bears hundreds 
of thousands of seeds. These fall to the ground, and many are 
eaten by birds, insects, and animals; some decay. Others:alight on 
favorable spots and germinate the following spring, but these seed- 
lings which start in the shade of the virgin forest are almost sure to 
a 
