32 BULLETIN 475, U. S. DEPARTMENT OF AGRICULTURE. 
in the trees in hot, exposed situations and against their heating in 
the bundles, crates, or while heeled in. 
Pains should be taken during the actual planting to observe the 
following: The planting holes should be deep enough (10 to 12 
inches) and broad enough (8 inches or more) to accommodate fully 
the roots of the planting stock; the planting should be neither too 
deep nor too shallow; the soil packed around the roots should be 
moist and well firmed ; the more fertile upper layers of soil should 
be packed around the roots, but sod should be excluded because it 
leaves air spaces and causes the drying out of the roots and the death 
of the plant; and depressions should not be left around trees planted 
under aspen or deciduous brush or on steep slopes (fig. 5). 
QUANTITY OF SEED AND NUMBER OF PLANTS PER ACRE. 
In the forest nature produces seed abundantly, depending upon 
quantity to offset possible adverse conditions. In artificial sowing it 
is not practicable to be so lavish ; and conditions that will permit the 
germination of the seed and enable the plants to grow must, so far 
as possible, be insured. One of the chief problems is to get the seed 
into direct contact with the soil. An old grove of Douglas fir trees 
may shed 25 pounds of seed to the acre, or 1,250,000 individual seed; 
yet, because of needles and litter covering the ground, very few seed 
reach the mineral soil, germinate, and grow. With Douglas fir direct 
light is, of course, an important factor also. By removing the heavy 
shade, burning the litter, and exposing the mineral soil, and by 
poisoning destructive rodents, conditions may be so improved that 3 
pounds of seed to the acre, sown broadcast, or 1 pound sown in seed 
spots, will produce a full stand of young trees. Areas sown by the 
seed-spot method suffer more damage from birds than do those sown 
by other methods. A thicker sowing in the spots is therefore neces- 
sary. 
Table 5. — Approximate percmtage of germination of fresh seeds of different 
species under greenhouse conditions} 
Species. 
Germina- 
tion. 
Species. 
Germina- 
tion. 
Bigtree (Sequoia washingtonia) 
Arizona cypress (Cupressns arizonica) . . . 
Amabilis fir (Abies amabilis) 
Douglas fir (Pseudotsuga taxifolia) 
Grand fir (Abies grandis) 
Noble fir (Abies nobilis) 
Red fir (Abies magnifica) 
Austrian pine (Pinus austriaca) 
Lodgepole pine (Pinus raurrayana) 
Mexican white pine (Pinus strobiformis) . 
Per cent. 
33 
22 
2 42 
55 
2 34 
223 
2 65 
67 
86 
83 
47 
Norway pine (Pinus resinosa) 
' Scotch pine (Pinus svlvestris) 
Sugar pine (Pinus lambertiana) 
Western white pine (Pinus monticola). .. 
Western- yellow pine (Pinus ponderosa) . . 
White pine (Pinus strol)us) 
Western red cedar (Thuja plicata) 
Engelman spruce (Picea engelmanni). . . 
Norway spruce (Picea exceisa) 
Sitka spruce (Picea sitchensis) 
Per cent. 
89 
44 
51 
57 
75 
55 
67 
60 
48 
51 
1 Individual lots of seeds vary greatly in their germinative ability. Under field conditions, germination 
is usually less than in the greenhouse. 
2 Tests not xnade by the Forest Service. 
