220 DRY-FARMING 
draw freely upon the stored soil-moisture. This 
method makes fall germination sure in districts 
where the natural precipitation is not to be depended 
upon. 
When sowing is done in the spring, there are few 
factors to consider. Whenever the temperature is 
right and the soil has dried out sufficiently so that 
agricultural implements may be used properly, it is 
usually safe to begin sowing. The customs which 
prevail generally with regard to the time of spring 
sowing may be adopted in dry-farm practices also. 
Depth of seeding 
The depth to which seed should be planted in the 
soil is of importance in a system of dry-farming. 
The reserve materials in seeds are used to produce 
the first roots and the young plants. No new nutri- 
ment beyond that stored in the soil can be obtained 
by the plant until the leaves are above the ground, 
able to gather carbon from the atmosphere. The 
danger of deep planting lies, therefore, in exhausting 
the reserve materials of the seeds before the plant 
has been able to push its leaves above the ground. 
Should this occur, the plant will probably die in the 
soil. On the other hand, if the seed is not planted 
deeply enough, it may happen that the roots cannot 
be sent down far enough to connect with the soil-— 
water reservoir below. Then, the root system will 
