316 HOW CROPS GROW. 



At 65 the grains, clover, peas, and flax, began to sprout 

 in one to two days ; maize, beans, and sugar-beet, in 3 

 days, and tobacco in 6 days. 



The time of completion varies with the temperature 

 much more than that of beginning. It is, for example, ac- 

 cording to Sachs, 



at 41- 55 for wheat and barley 40-45 clays, 

 " 95-100 " " " " 10-12 " 



At a given temperature small seeds complete germina- 

 tion much sooner than large ones. Thus at 55-60 the 

 process is finished with beans in 30-40 days. 



With maize in 30-35 days. 

 " wheat "20-25 " 

 " clover " 8-10 " 



These differences are simply due to the fact that the 

 smaller seeds have smaller stores of nutriment for the 

 young plant, and are therefore more quickly exhausted. 



Proper Depth Of Sowing. The soil is usually the me- 

 dium of moisture, warmth, etc., to the seed, and it affects 

 germination only as it influences the supply of these 

 agencies ; it is not otherwise essential to the process. The 

 burying of seeds, when sown in the field or garden, serves 

 to cover them away from birds and keep them from drying 

 up. In the forest, at spring-time, we may see innumerable 

 seeds sprouting upon the surface, or but half covered with 

 decayed leaves. 



While it is the nearly universal result of experience in 

 temperate regions that agricultural seeds germinate most 

 surely when sown at a depth not exceeding 1-3 inches, 

 there are circumstances under which a widely different 

 practice is admissible or .even essential. In the light and 

 porous soil of the gardens of New Haven, peas may be 

 sown 6 to 8 inches deep without detriment, and are 

 thereby better secured from the ravages of the domestic 

 pigeon. 



The Moqui Indians, dwelling upon the table lands 



