The Bulletin. 47 



time ago I asked one of the best of these farmers how many good crops he 

 could count on getting in five years. His reply was : "If I can get one in ten 

 years I am doing well." Some years ago alfalfa was accidentally introduced 

 into the limestone soils of the black belt and success has finally come to the 

 farmers of that section. This type of soil is the native home of alfalfa, 

 melilotus, etc., and these legumes alone have raised the price of these fertile 

 lands from five to fifty dollars an acre. 



Not only the crop in general is determined, or should be determined by the 

 soil type, but the quality of product is frequently affected by the soil environ- 

 ment. It has been found in forestry investigations that two nuts taken from 

 the same hickory tree and planted on two distinct soil types, the one will 

 develop a tree with wood having great strength and elasticity, while the 

 other will produce a tree with wood lacking in these qualities, but possessing 

 great polishing powers.* In the coastal plain there are two types of soil that 

 are distinct, yet possessing some points of close similarity. One of these is 

 known as the Norfolk, the other as the Orangeburg, fine sandy loam. When 

 sugar-cane is grown on the Orangeburg soil the syrup manufactured from it 

 has a dark-red color, while that produced from cane grown on the Norfolk 

 soil has a beautiful amber color, thus giving it a much higher market value. 

 The same is true in regard to tobacco, peaches, apples, oranges and other 

 fruits; the soil type has a most pronounced influence on the quality of the 

 product. 



But the most important discovery in this field is not general adaptation of 

 plants to soil types, not that some soils will grow some crops better than they 

 will grow others, but that certain soil types are better suited to the production 

 of some varieties of crops than are other soils. It appears from our study of 

 the subject that when a crop is grown continuously on a definite soil type for 

 a number of years and careful seed selection is practiced during its growth, 

 that there is a strong tendency for the plants to become attached to the condi- 

 tions existing in this soil ; they make for themselves a congenial home, become 

 adapted to the given soil condition, adjusted to the environment, so that noth- 

 ing interferes seriously with their proper performance of duty. 



Looking at the proposition from a different angle we might say that the soil 

 type which is the result of the combination of a number of factors so influ- 

 ences the crop that grows on it that the plants undergo, or may undergo, a 

 gradual change which fits them more and more to grapple with the new condi- 

 tions of fertility under which they are placed. 



Speaking broadly, soil types are eternal things, whereas plant varieties are 

 subject to easy and rapid change, being influenced by every radical change of 

 environment. This influence is shown in a variety of ways, as in the change 

 in shape of stalk, size of fruit, size of leaf and, generally, decreased pro- 

 lificacy. While it is the influence on the prolificacy in which we are chiefly 

 concerned, the influence on the quality of the product is by no means unim- 

 portant. 



It is well known that the agricultural press spreads before the farmers 

 yearly the names of a large number of varieties of corn, cotton, wheat, etc. 

 The good qualities of these varieties are enlarged upon, but no indication is 

 given as to whether they will make good yields on your particular farm or on 

 any one of the half dozen kinds of land found on it. Yet the best of these 

 varieties have been developed, so far as our present knowledge is concerned, 

 on a distinct and definite type of soil and under a definite fertilizer and cul- 

 tural treatment. Unfortunately, however, this most essential information is 

 rarely found in the press, because the originators of these varieties either 

 think it useless to give it or feel that their varieties will do well under all 

 sorts of conditions. 



In the case of live stock, each breed or strain is developed to meet some 

 special demands ; so, also, in plants, in general, a variety is a result of a defi- 

 nite set of environmental conditions that have combined to produce the varia- 

 tions that go to make the new strain. The variety, then, is the result either, 

 of changed natural conditions or of effort along lines carefully laid with a 



•Collier Cobb: Geology and the Lumber Trade. 



