408 Transactioxs of the American Institute. 



fertilizing matter, and tlie more these fertilizers, this vegetable matter 

 is kept together, the richer the soil must be ; and as vegetable mold 

 is the best material to retain moisture or retard evaporation, and as 

 it is proven that the feeders of all plants run near the surface, there- 

 fore, the more this vegetable mold is contracted and kept near the 

 surface, the better it will withstand dry weather and supply food to 

 the plants. 



All soils are considered as originally merely disintegrated rock, 

 and exclusively mineral, or a mineral basis in combination with 

 oxygen. All plants have more or less of mineral constituents. 

 Silex, or sand, is a necessity in the maturing or strengthening of the 

 straw of wheat. Lime will often double the- crops of oats or peas. 

 But no land would pay for cultivation that was exclusively mineral. 

 It must contain humus, or vegetable mold, and the more the better, 

 provided there are also the minute portions of mineral ingredients 

 that plants require. This humus is the residuum of decaying plants 

 since the creation; and, judging from the depth of the soil as found 

 in primitive forests, some kinds of mineral soils are better than others. 

 "Where all is land w^e find stunted pines, and the humus or leaf mold 

 is but a mere crust. In districts where the timber is heavy the soil 

 will be five or six inches in depth. The depth of the virgin soil in 

 that portion of Salem county we saw is generally from three- to four 

 inches. By good farming and free use of fertilizers that soil has been 

 made to produce seventy, eighty, and even 100 bushels of shelled 

 corn to the acre, without plowing deeper than this native soil. Your 

 committee will not say that the limit of productiveness in Salem 

 county has been reached ; that would be a hazardous assertion. 

 But where we see a whole neighborhood of such intelligent 

 farmers producing such superb crops by shallow plowing, and the 

 most of them lessening the depth by increased experience, we feel 

 that we may cite their example as a caution against the indiscrimi- 

 nate adoption of a deep system of tillage. A part of your committee 

 subsequently visited portions of Delaware and Chester counties, in 

 Pennsylvania. "We saw mam'- of the celebrated grazing farms of the 

 Brandywine hills. In Salem the staple crop was corn, and that cro]) 

 had then increased just in proportion as they had diminished the 

 depth of plowing. Upon the Brandywine farms the staple was beef, 

 and the best ])asture fields there were those that had never been 

 plowed at all. It is what is usually called the soil that is to produce 

 the crop. Take that off, as is sometimes done in making basin or 



