DIRECT SEEDING. 35 



Areas sown by the seed-spot method suffer more damage from 

 birds than do those sown by other methods. A thicker sowing in 

 seed spots is therefore necessary. Where, however, too many seed 

 are used per spot, and these are unmolested, the resulting growth 

 is much too thick, and the tree trunks do not develop normally. The 

 interior trees are too slender, and the competition for light and moist- 

 ure during the early stages of growth is too great. Moreover, the 

 completion of a fully stocked stand is retarded, and soil protection 

 is in consequence postponed for a long time. 



The so-called hole or pit method of direct seeding is the same as 

 the spot method. The prepared spot is smaller and somewhat deeper. 

 It is used on very dry, barren, stony ground, in sunny, hot, or windy 

 situations. 



QUANTITY OF SEED PER ACHE. 



In the forest during most years 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 tiny 

 plants to grow must 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 indi- 

 vidual seeds, yet because of needles and litter covering the ground 

 probably less than one seed in ten thousand reaches the mineral soil, 

 germinates, and grows. With Douglas fir direct light is, of course, 

 an important factor also. By removing the heavy shade, by 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. 



With a suitable area well prepared, the amount of seed of the more 

 important species required per acre is about that shown in Table 10. 

 The amounts are based on the average germination per cents given in 

 Table 9. The Forest Service seed testing laboratory annually de- 

 termines the germination per cents of the seed collected on different 

 forests, and the amount sown per acre should be varied in accordance 

 with these tests. 



