ESTABLISHING FORESTS BY DIRECT SEEDING 209 



time of sowing has a direct bearing upon the degree of 

 success attainable in direct seeding. In a country as large as the 

 United States with its great variety of economic species and wide 

 diversity in climatic conditions, no particular season can be said 

 to be the best time for direct seeding. The time'of sowing de- 

 pends chiefly upon: 

 j a. The characteristics of the species. 

 X, b. The climatic conditions. 



Seeds maturing before midsummer should be sown at once be- 

 cause of the difficulty of keeping them until the following spring. 

 Were it not for the danger of being destroyed either by animal 

 life or by adverse climatic conditions while lying on the ground 

 over winter, direct seeding in the autumn would be acceptable for 

 all autumn-maturing seeds. All species which naturally germinate 

 in the spring can be sown either in the autumn or in the spring. 

 Seeds which can be easily stored with little danger of deterioration 

 and at small cost are sown in most localities in the early spring. 

 Because of their rapid deterioration when stored, birch, alder, and 

 fir seeds are often sown in the autumn. Chestnut deteriorates 

 rapidly under storage and, when the seed can be protected from 

 animal life, should be sown in the autumn. Walnut, hickory, oak, 

 and beech are sometimes sown in the autumn. 



In the more southern parts of the United States the season of 

 the most abundant rainfall is a determining factor in seeding. 

 On the Pacific coast where the rainy season is in winter, direct 

 seeding should be done in January or February or in late autumn 

 in order that the seed coats may become thoroughly soaked and 

 be in condition for germination during the first warm days of 

 spring. Early seeding is very important in order that the young 

 plants may become well established before the summer drought 

 begins. 



({) Insufficient covering is one of the chief reasons why so few of 

 the viable seeds in natural regeneration germinate and become 

 established. Only a comparatively small percentage of the total 

 fall of seed is carried by the winter and spring rains into the 

 mineral soil or even down to it. If the cover is too thin, its 

 full value as a protection against the drying and carrying 

 away of the seed by wind, water, and animal life is not fully 

 attained. If too dense, germination is retarded or it may fail 

 altogether. 



