PASTURES, MEADOWS, AND FORAGE 



199 



313a. Observe how different the roots of clover and timothy 

 are (Figs. 79, 80). One feeds in the subsoil and subsurface 

 soil, has many little organisms on its rootlets, which are called 

 nitrogen-fixers (138); that is, they take the free nitrogen of 

 the soil air, and it then becomes of use to the plant. 

 The timothy has many small fibrous roots, which remain near 

 the surface, and have no nitrogen-fixing organisms. It will be 



Fig. H2. Alfalfa or lucerne (Medicayo 

 satica> x>. 



Fig. 83. A good bottle for 

 seeds. 



seen how appropriate it is to raise these plants together : one 

 feeds near the surface, the other down deep in the soil ; one 

 is long lived, the other short lived. 



318a. In general farming, the most uniformly good crops 

 are nearly always obtained when a rotation is used. Fig. 81 

 is a field of wheat, in a rotation, which yielded over 30 bushels 

 to the acre. 



323. The permanent meadows teach many valuable lessons 

 if they are studied closely. Here is often found a marked illus- 

 tration of the struggle for existence and of the survival of the 

 fittest. Here the farmer can give little help by tillage, and 



