126 AGRICULTURE. 



or vetch, to prevent the leaching" out of valuable 

 fertilizing materials by the rains. 



The seeds make a valuable concentrated food, 

 but since, as yet, there is no means of thresh- 

 ing them satisfactorily unless gathered by hand, 

 it is quite expensive. 



V. The Soy-bean (Glychie hispida) 

 (Fig. 34) is largely grown in the South, Init can 

 be grown w^herever Indian corn can be grow^i 

 successfully. It feeds heavily upon potash, and 

 requires fertilizing with lime, potash, and phos- 

 phorus if the soil is poor in these materials. It 

 should not be planted until the ground is w^arm. 

 It growls rapidly, and generally requires little 

 cultivation. 



The hay is rich in protein. It should be cut 

 at the time of, or soon after, blooming. The 

 seed yields from twenty-five to forty bushels per 

 acre. The beans are rich in protein and oil, 

 hence they make a desirable concentrated food 

 to be fed in connection with roughage. 



Exercise 5. — {a) Collect specimens of various legu- 

 minous plants, taking great care to procure the root 

 systems intact. 



(/>) Look for tubercles or nodules on the roots. Where 



found ? 



{c) Note the relative size of nodules upon different 

 kinds of plants, and upon the same kind of plants 

 grown in different soils. 



{d) Do you find any legumes which have no nodules? 

 If so, test the soil in which they were grown for acid. 



