No. 6. DEPARTMENT OF AGRICULTURE. 719 



tion of moisture. If land have plenty ot liumus, or if it be so located 

 that autumn rains may be counted upon with some certainty, there 

 is much in favor of growing the crop in the cool days of fall. The 

 season of cultivation is shorter, there is better control of weeds, 

 early blight is less to be feared, and there are fewer insect enemies. 

 As a rule, moreover, when June-planting does succeed, the yields of 

 these late-planted fields exceed the yields from early planting, so 

 that decreased expense in growing is attended by increased yields. 



One serious objection to late potatoes is interference with a crop 

 rotation that is desirable in the belt of which I write. For thirty 

 years in my own experience have I noted the advantages of a three- 

 3 ears' rotation of potatoes, wheat and medium red clover. Potatoes 

 pave the way for wheat, giving a nearly perfect seed-bed, but this 

 is possible only with the early-planted crop. I do not mean early 

 varieties, necessarily, but medium varieties, like the Carman, planted 

 very early, which make their crop before fall, and can be harvested 

 before time for firming the seed-bed for fall grain. A late crop of 

 potatoes does not get out of the way for fall seeding, and disrupts 

 one of the best crop rotations known. 



There is the additional objection, and a most serious one for the 

 belt of which the fortieth parallel of latitude is a central line, that 

 the crop comes into the most direct competition with the northern 

 potatoes that are grown undier the most favorable climatic condi- 

 tions and can be placed upon the market more cheaply than our more 

 southern crops. I incline to think that the best money has been 

 made in late years by those growers who had a ripened crop ready for 

 market before frost. The autumn frosts stop the growth in the 

 northern fields, and there is a rush of their product upon the market 

 that nearly invariably causes a decline in price. 



The disadvantages of early planting may be great. Heavy 

 spring rains are not infrequent, and cause some rotting of seed. 

 They jjack the soil seriously, undoing much of the work of preparing 

 it for planting. Late frosts may cut the tops, and such damage can^ 

 not be fully repaired by the plant. The stem underground may not 

 rot, but it sends out too many branches to take the place of the old 

 top, and the yield is rarely, if ever, satisfactory. The potato beetles 

 and the flea beetles time their arrivals to catch the early-planted 

 fields at a tender stage. But in very much of the belt of country 

 mentioned there are advantages that counterbalance all disadvan- 

 tages. A chief one is the probability of a better supply of moisture 

 in the first half of the year than in the latter half. There may be no 

 more rainfall, but evaporation is less rapid. Indeed in this belt the 

 area devoted to a late-planted crop is far smaller than that given 

 to early planting, experience having demonstrated the danger of 

 drouth in September. The time of planting is a matter to be de- 



