92 



MASS. EXPERIMENT STATION BULLETIN 240 



the control of the individual farmer on a particular farm. Of the factors with- 

 in his control, seed and fertilizer are the most important, a fact established 

 by several investigators. Spraying is also an important factor, affecting- 

 yields especially in years when disease is prevalent. The data secured in this 

 study do not lend themselves to a determination of the most profitable rates 

 of seeding and fertilizing because of the variation in soils and previous crop- 

 ping on the farms studied. However, Hardenburg,' after analyzing several 

 hundred potato records from various parts of New York, found that very few 

 growers liad exceeded the optimum rate of seeding. Black, Tolley, and EzekieP 

 witii 300 farm records from Monroe County, New York, found the same to 

 be true botli witli seed and fertilizer. 



Figure H. Average Yield per Acre of Potatoes in 

 Maine and Massachusetts (5 year averages.) 



Bushels 



200 



150 



50 



Yields in Maine have increased with improved seed, more adequate disease control, 

 heavier applications of fertilizer, and commercialized practice in general. Yields in 

 Massachusetts have advanced less rapidly. 



Tiie high yields in Maine have lieen obtained only in recent decades. They 

 were formerly as low as in Massachusetts. The changes in yields in Maine 

 and Massachusetts by 5-year periods are shown in Figure 11. The more 

 rapid increase in Maine has been due to several factors. Certified seed, heavier 

 rates of fertilizing, more adequate spraying, the opening up of the Aroostook 

 country, and large commercial potato farms are among tiie causes. Production 

 in Massachusetts has continued to be on general farms, and supplementary to 

 other enterprises. 



' Hardenburg, E. A'. A Study, by the Crop Survey Method, of Factors influencing 

 the Yield of Potatoes. New York (Cornell) Agr. Exp. Sta. Memoir 57, 1922. 



" Tolley, H. R., Black, ,T. D., and Ezekiel, M. J. B. Input as Related to Output in 

 Farm Organization and Cost of Production Studies. United States Department of 

 Agriculture. Bulletin 1277. 1924. 



