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same lot was added. If there is anything practical in the influence of the 

 bacterial life. I fail to see why. by some such inoculation tests, it may not be 

 shown. To the possible objection that it was a case of inoculating with mixed 

 cultures arises the fact that a pure culture introduced into an ordinary soil 

 might not better the conditions. If benefit is found to follow such work, 

 specialists may well be set at work to ascertain to what specific organisms the 

 differences are due. This would seem to be a very suggestive line of work for 

 neglected soils. 



There is another much neglected line of soil investigation. We bear much 

 talk about soils and their influence upon the growth of plants. We have not 

 liad the means to study this subject in Rhode Island except incidentally, but 

 we have tested the effect of probably about 200 different varieties of plants to 

 see how they would be affected by certain differences. Reference is made to 

 two plats of land where sulphate of ammonia has been used with and without 

 lime, and to two other plats where nitrate of soda has been similarly used. 

 In the case of a few plants liming was injurious in both instances, but for 

 most plants liming was beneflcial or absolutely essential to their growth. In 

 view of such diametrically oi)i)osite results I do not think we should talk about 

 the condition of soils without considering in the same connection the crops that 

 are to be grown. The two can not be divorced. There are some plants which 

 liave twice the range of adaptability of others, and a study of the special range 

 and adaptability of plants to these different soil conditions must not be left 

 out of consideration in connection with soil investigations. 



We had a very interesting experience two or three years ago where we had 

 tried nine different phosphates. We planted several varieties of plants across 

 these plats and obtained certain results. The next year a single variety was 

 gi-own niton all of these plats, and you could go out there and see by the varia- 

 tions in height the marked influence of the previous crop upon the one which 

 bad followed. Whether that was entirely caused by removal of plant food, 

 whether it was due in part to the influence on the physical condition, or to 

 some noxious influence ofthe previous crop, or to other causes, has not been 

 ascertained. There should be in connection with soils a very careful study of 

 the effect of given plants upon the particular plant which is to follow. In other 

 words. 1 think there should be a study of rotations with this specific object in 

 A lew. .Vt present I do not know of a single comprehensive and specific experi- 

 ment of this kind in progress in this country or in Eui'ope. It would seem as 

 if these factors have not been sufficiently taken into account in our studies of 

 soil treatment and soil re(|uirements. 



Another (piestion which interests me very much is the influence of the texture 

 of the soil upon the growth of plants. As we all know, there have been a 

 number of experiments conducted under glass, which show that one can not 

 grow lettuce successfully in a compact, heavy soil, and yet carnation pinks will 

 thrive well in it. There is a great difference in plants as concerns the texture 

 of the soil best suited to them, and I believe we nmst study our soils more, with 

 this point in view. Take for example one of our old exhausted soils in Rhode 

 Island, which has ;U jier cent of humus. It is so fine, so compact, and of such 

 poor texture that with liberal manuring with chemicals one can not secure at 

 the outset a good cni]) of Indian corn or of potatoes; and yet it will yield a 

 sitlendid crop of rye. From these things I am led to believe that there is a 

 great field for investigation in finding out the influence of texture upon the 

 growth of crops. This matter, if understood, will influence the arrangement of 

 crops in rotations. If we have a poor textui'e of soil we must put on first a 

 < rop that will grow under those conditions, and toward the end of the rotation 

 we can grow plants which demand a better texture. I may be mistaken 



