84 



OUTLINE OF CROP MANAGEMENT 



The double-shovel plow in 1820, used until 

 very recently. 



Fig. 112. A threshing device as pictured in 1845 (Wanen's horse-power and thresher). "Themaehinesmay be placed as follows, 

 viz.: The horse-power, Fig. 1, and the pulley-box. Kg. 3, outside the barn, and the threshing machine. Fig. 2, inside any 

 convenient distance, say about 4 feet." 



general increase in yield was 400 to 500 per cent. This shows that a plain rotation is itself capable 

 of increasing yield, but that a greater increase is to be expected by a combination of rotation and 

 manuring. 



The iirst rotation-farming to gain wide attention in North America seems to have been the so-called 

 Norfolk system. This was chiefly a four-crop rotation employed on the light lands of Norfolk, England, 

 and which had grown up during a long course of years. A century and more ago this system was 

 explained by writers and thereby became widely known, the more so because at that time the American 

 agricultural literature was drawn chiefly from English sources. An account of " the Improvements made 



in the County of Norfolk" comprised the larger part 

 of Jared Eliot's "Fourth Essay upon Field Husbandry," 

 published at Killingworth, Connecticut, in 1753. The 

 exact rotation itself — comprising roots, barley, clover, 

 wheat, in various combinations — was of less impor- 

 tance to the American colonies than the fact that 

 attention was called to the value of rotation-farming 

 in general. At the same epoch another system of 

 farming practice was also coming in from English sources. This was the clean- 

 tillage system introduced by the epoch-making experiments of Jethro Tull. 

 Between the discussions of the Tull " new husbandry " and the Norfolk rotations, 

 agricultural practices were challenged and overhauled in the new 

 country. 



One of the early explanations of the good -results of rotation of 

 crops was the doctrine that some plants exhaust the soil of certain 

 materials which are not needed by other plants ; therefore the value 

 of rotation depended on securing such a combination of crops as would 

 in time utilize all the elements of the soil. There is, of course, some 

 truth in this teaching, but we now know that the question is by no 



means one of so-called exhaustion alone. 

 Another explanation was found in the 

 theory that roots excrete certain sub- 

 stances that are noxious to the plants excreting them and innocuous or 

 even beneficial to other plants. The excretory theory was taught early in 

 the past century by the renowned Swiss botanist, Pyramus de Candolle. It 

 was no doubt a suggestion from the animal kingdom. This theory was 

 practically given up before the middle of the past century. Yet it is most 

 interesting to find recent experiments in England on the growing of grass 

 in orchards leading to the suggestion that one plant may exert some influ- 

 ence on the soil deleterious to another plant. It is suggested that this 

 influence, however, is biological rather than chemical — in some way, per- 

 haps, concerned with the little-understood germ life of the soil. Recent 

 publications by the United States Department of Agriculture (Bureau of 

 Soils) state that root excretions are probably very intimately associated 

 lis The Geddes harrow ^^^^ ®°^^ productivity, that much of the value of manurial substances lies 

 1845. Price $12. in the cleansing of the soil of these toxic excreta, and that the value of 



Fig. 114. Picture of a cultivator attend- 

 ing an advertisement in "American 

 Farmer, ' ' 1821. ,The advertisement 

 also says that "persons transmit- 

 ting the cash for any of the follow- 

 ing articles, will be carefully put 

 up and shipped to any part of the 

 United States : Clover, Timothy 

 and other grasses and garden seeds 

 warranted of good Quality." 



