FARMERS' INSTITUTES. 51 



the bacteria which develop the root tubercles. Experiments have 

 proven that in the absence of these bacteria, even with all the elements 

 of plant growth except nitrogen in other forms than that of the air, 

 the legumes will even then refuse to grow. This experiment has led 

 to the practice in some places of inoculating the soil where the partic- 

 ular legume crop has never, or not for a long time, been grown, in 

 order that the development of the root nodules may be encouraged. 

 An enterprising German scientist has even gone so far as to prepare 

 and offer for sale a bacterial culture known as "Nitragin," which, if ap- 

 plied to the seed, will introduce into the soil the necessary bacteria 

 to encourage the assimilation of atmospheric nitrogen. 



Lawes and Gilbert early observed that the wheat crops following 

 clover were always larger than when they succeeded any other crop. 

 These investigators reasoned that the clover roots, stubbles and dry 

 leaves left more fertility in the soil than was removed in the clover 

 crop. One of their early experiments was on a field which had grown 

 six successive crops of cereal, and then divided into halves, the one 

 half growing barley and the other clover. After these crops were har- 

 vested analysis of the soil showed it to contain on the barley ground 

 .1416 per cent nitrogen, and on the clover stubble .1566 per cent nitro- 

 gen, an increase of over 10 per cent in favor of the clover. The crop 

 following these was barley again, which yielded 33 bushels per acre 

 on the barley ground and 58 bushels per acre on the clover stubble. 



LIST OF LEGUMES. 



The family of Leguminosae is a very large one, including many culti- 

 vated farm crops, shrubs and trees. Those with which we are most 

 familiar are the clovers — ;red, mammoth, alsike, crimson, white and yel- 

 low; bean and peas, including all garden and field varieties, cow peas, 

 soy beans, velvet beans, etc.; vetches — sand, winter or hairy vetch, and 

 tares; lupines — blue, white and yellow; lucernes — alfalfa, sand lucerne 

 and the lucerne rustique; serradella fennugreek, etc. The root nodules 

 mentioned above can usually be found by carefully lifting any one of 

 the above growing plants, taking pains not to strip off the nodules 

 as the roots are pulled out of the ground. The nodules appear in vari- 

 ous forms, sometimes in clusters, others growing tightly around the 

 roots like beads on a string, and others as large, warty-like growths at 

 the extremities of the rootlets. 



TEST OF VARIETIES OF CLOVER. 



Four varieties of clover have been tested the past year on the College 

 farm, including the alsike, Russian, medium or June, and mammoth. 

 The seed was sown as a single crop, given entire possession of the 

 ground, and cared for during the summer by simply mowing twice 

 with a mowing machine, the knives set high, to keep down the growth 

 of weeds. The clover catch was perfect and the resulting crop was as 

 follows: Alsike, 5,264 pounds; Russian, 4,144 pounds; June, 3,600 

 pounds; and mammoth, 3,260 pounds per acre. While these figures 

 may not warrant the drawing of a conclusion as to the best variety, in 

 accordance with this experiment, the fact that this method of seeding 

 resulted in a perfect catch and a satisfactory crop recommends this 

 system of seeding. 



