102 ' - v ; l - : vOJHJ^ BOOK ,OF WHEAT 



United Kingdom decreased over one-third while the yield in-- 

 creased one-sixth. In the same period the acreage of France in- 

 creased about one-eleventh, while the yield increased less than 

 one-ninth. Presumably both countries made approximately the 

 same advance in the arts, that is, in methods of production. It 

 does not appear that there ever was a case where an advance in 

 the arts supplanted with wheat a crop more profitable than 

 wheat was before the advance. In increasing her acreage France 

 had to utilize lands of lower yield, thus reducing the average 

 yield of all, while the United Kingdom raised the average by 

 exactly the opposite process, namely, by reducing her acreage 

 in ceasing to sow to wheat those lands of such a low yield as to 

 be unprofitable. 



In the United States the causes and effects cannot be traced 

 easily or clearly. We see that the greatest increase in acre- 

 age was in the eighth decade, but this acreage was located in the 

 Mississippi and Red river valleys. It consisted of some of the 

 most fertile land of our country, and proved to be better wheat 

 land than any which had previously been sown in that grain. 

 Consequently, it was but natural that the yield should rise, es- 

 pecially as there had been but little intensive farming. The 

 rise in yield would doubtless have been constant since that date, 

 had it not been for abnormal natural conditions which seem to 

 have decreased the actual yield slightly in the ninth decade, al- 

 though the potential yield has increased uninterruptedly. Since 

 the ninth decade the increase in acreage has been comparatively 

 rapid, doubtless largely due to great improvements in machin- 

 ery, but the arts have advanced rapidly enough to more than 

 counteract these results. The average yield from 1866 to 1886 

 was 12.2 bushels per acre, while that from 1886 to 1906 was 

 13.7. There is such a great annual variation in yield that 

 statistics are not conclusive unless they are averages extending 

 over at least a decade. 



Columella gives 19.5 to 27 bushels as the amount of wheat 

 that the Romans raised per acre. From 1200 to 1500 England 

 raised 4 to 8 bushels per acre, while she raises about 30 now. 

 The testimony of a contemporary observer shows the yield of 

 wheat near Philadelphia in 1791 to have averaged less than 8 

 bushels per acre. It is now more than twice that amount. The 

 greatest yield of wheat in the United States seems to be in the 



