ALFALFA, FORAGE CROPS AND PASTURES 271 



the last harvest, when the plants are dormant. Open, 

 dry winters are not conducive to good alfalfa yields. A 

 soil of low water content in winter is not so satisfactory for 

 alfalfa as one that is near field saturation. However, too 

 much water is equally harmful, and may cause winter- 

 killing. Free water, found in the upper foot or two of the 

 soil, freezes in seasons of high cold, and serious injury 

 is done the plants. The alternate freezing and thawing 

 of some winters is even more injurious to the crop. If 



FlQ. 68. Temporary county fair building constructed of baled alfalfa hay. In a 

 pioneer section. 



water is allowed to form ice over the surface, the alfalfa 

 plants are fatally injured. The soil should not be too wet 

 in the spring, for the low temperature of the soil induced 

 by the presence of much water will tend to retard the 

 early and important spring growth. 



After the spring growth has begun, the first irrigation 

 should be postponed for some weeks, although it is not so 

 important to do this with alfalfa as with the annual crops 

 that are irrigated late in order to drive their root-systems 

 downward. Where wheat is planted in April, the first 



