Relation of Weather to Crops 103 



The variety best adapted to forage production is the yellow- 

 sweet clover. This is a biennial and should not be confused with 

 the annual, Melilotus indica, a common variety growing in many 

 parts of the State as a weed pest under the name of "sour clover." 



Sweet clover should be sown in October or November on a well 

 prepared seed bed. It may be sown, like alfalfa, from September 

 to May. The best results, howcA^er, will be obtained by the fall 

 sowing. Especially is this true in the dry-farming sections, where 

 moisture conditions are more favorable at that time. 



Sweet clover, being a biennial, can be cut for hay the first 

 season, and harvested for the seed crop the second, after which it 

 dies. Sweet clover should be cut higher than alfalfa, as the new 

 g rowth comes from the axils of the lower branches, and not from 

 a surface crown. 



SWEET POTATOES 



Sweet potatoes may be grown in southern Arizona at altitudes 

 of less than 4500 feet, where water is available. They should be 

 started in a hotbed in February, and the slips transplanted to the 

 field as soon as danger of frost is over. Sweet potatoes do best in 

 well fertilized sandy soils, and should be frequently irrigated. They 

 require a long growing season and the yield steadily increases until 

 frost. No serious pests have been observed, and experience has 

 shown the crop to be sure and profitable. The Large White and 

 the Georgia Yam are juicy sweet varieties producing heavily. The 

 White Vinelefes is an excellent market variety. Yellow Jersey, South- 

 ern Queen, Shanghai, and Nansemond have also produced satis- 

 factorily. 



TOBACCO 



This crop has not been tested thoroughly at the Station Farm, 

 or elsewhere in the region, but the indications are that it may be 

 grown successfully. A fair crop was secured the one season it was 

 tested, and a fairly good product obtained. 



It can only be grown where irrigation is ample. The seed should 

 be sown early in a good cold frame where the little plants maybe 

 tended carefully. As soon as all danger of frost is past the plants 

 may be transplanted to the field. 



TOMATOES 



Like potatoes, tomatoes are sensitive to both heat and cold' 

 though not quite as sensitive to either. Tomatoes differ from pota- 



