355 



vitality of the seed, due to unknown causes, and which we have no 

 means of measuring except by just such experiments as these. The 

 elaborate measurements made by Lawes and Gilbert at Rothamsted, 

 England, since 1850, furnish innumerable illustrations of this same 

 principle; so, also, do those of ^Y. R. Lazenby, at Columbus, Ohio, 

 and many others. 



"We shall therefore hope to derive more reliable results from the 

 study of farming operations on a large scale, taking the averages by 

 counties and States where the crops have been carefully measured. 

 We may possibly eliminate irregularities in many disturbing ele- 

 ments, and be able to clearly set forth that small percentage by which 

 the crops of the United States as a whole are influenced by purely 

 climatic conditions. Such influences may in extreme cases be very 

 large, but, on the average, they are not so large as those which depend 

 upon seed, cultivation, rotation, and fertilizers. 



EFFECT OF VARIATIONS IN METHOD OF CULTIVATION AND IN 

 aUALITY OF SEED FOR DIFFERENT REGIONS AND YEARS. 



Among the modes of cultivation that materially affect the devel- 

 opment of the plant and the quantity of the harvest must be consid- 

 ered the practice of sowing seed broadcast with the hand as con- 

 trasted with that of putting it in wdth the drilling machine. The 

 drilling requires less seed, the saving being about one-half bushel 

 per acre; the grain is buried more evenly, starts more uniformly, and 

 stands the droughts better. Moreover, the drilled wheat fields are 

 considered to yield more per acre, although it is difficult to state how 

 much is due to the drilling independent of the character of the soil, 

 because in general the fields that are drilled are most apt to be those 

 free from stumps, stones, and steep slopes, while the broadcast sow- 

 ing is especially adapted to this latter character of field. The census 

 of 1879 shows that the drilled fields of winter wheat in Ohio yielded 

 50 per cent more than the broadcast fields of sunnner wheat in the 

 Northwest ; but it is not plain w^hat proportion of this is respectively 

 due to the drilling and to the soil. 



In the report for 1875 of the Department of Agriculture (p. 42) 

 the follow^ing statistics are given as to the percentage of area drilled, 

 the quantity of seed per acre, and the increase of harvest in drilled 

 fields over that in broadcasted fields : 



The following table omits the New England States, which produce 

 little wheat, neai'ly all of which is sown broadcast. The wheat area 

 of New York is divided efjually between the two methods. In New 

 Jersey, Pennsylvania, Delaware, and Maryland the drill greatly 

 predominates. Tn the Soutliern States the area is small, particu- 

 larly in the cotton States, and the drill is comparatively unknown. 

 North of the Ohio River, in the winter-wheat States, the drill is very 



