GERMINATION. 317 



of the higher Colorado, deposit the seeds of maize 12 or 

 14 inches below the surface. Thus sown, the plant 

 thrives, while, if treated according to the plan usual in the 

 United States and Europe, it might never appear above 

 ground. The reasons for such a procedure are the follow- 

 ing : The country is without rain and almost without dew. 

 In summer the sandy soil is continuously parched by the 

 sun at a temperature often exceeding 100° in the shade. 

 It is only at the depth of a foot or more that the seed finds 

 the moisture needful for its growth, — moisture furnished 

 by the melting of the winter snows.* < 



R. HoflTmann, experimenting in a light, loamy sand, upon 

 24 kinds of agricultural and market-garden seeds, found 

 that all perished when buried 12 inches. When planted 

 10 inches deep, peas, vetches, beans, and maize, alone came 

 up; at 8 inches there appeared, besides the above, wheat, 

 millet, oats, barley, and colza ; at 6 inches those already 

 mentioned, together with winter colza, buckwheat, and 

 sugar-beets ; at 4 inches of depth the above, and mustard, 

 red and white clover, flax, horseradish, hemp, and turnips ; 

 finally, at 3 inches, lucern also appeared. Hoffmann 

 states that tlie deep-planted seeds generally sprouted most 

 quickly, and all early differences in development disap- 

 peared before the plants blossomed. 



On the other hand, Grouven, in trials with sugar-beet 

 seed, made, most probably, in a well-manured and rather 

 heavy soil, found that sowing at a depth off to 1:|- inches, 

 gave the earliest and strongest plants ; seeds deposited at 

 a depth of 2^ inches required 5 days longer to come up 

 than those planted at f in. It was further shown that 

 seeds sown shallow in a fine wet clay required 4-5 days 

 longer to come up than those placed at the same depth 

 in the ordinary soil. 



Not only the character of the soil, which influences the 



* For these interoBtins facts the writer is indebted to Prof. J. S. Newberry. 

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