10 THE PLANT. 



ment of its roots. There are instances on record, where 

 parts of a wheat-field had been trampled down in the 

 winter by horses (by no means an uncommon occurrence 

 in the foxhunting districts of England), so far as to de- 

 stroy every trace of a wheat-plant, and yet next year's 

 crop turned out much more abundant on those very 

 spots than in any other part of the field. It is e\ddent 

 that, to outlive an attack of this kind, a plant must have 

 its principal roots spreading in the deeper layers of the 

 soil. In the developement of its roots and the power 

 of penetrating the deeper layers of the soil, the oat- 

 plant stands next to wheat, and wiU flourish in a 

 somewhat stiff soil ; but as in the superficial layers 

 also the roots of oats throw out a number of fine 

 feeders, m a lateral direction, it is necessary that the top- 

 soil should be rather hght and open. A light, open 

 loam, even if of no great depth, is particularly suited for 

 barley, which forms a network of fine comparatively 

 short root-fibres. Peas require a loose soil, with httle 

 cohesion about it, which will favour the spreading of the 

 soft root-fibres in the deeper layers also ; whereas the 

 strong woody roots of the horse-bean will ramify in all 

 directions, even in a heavy and more compact soil. 

 Clover, grass-seeds, and small-sized seeds in general, put 

 forth at first feeble roots of small extent, and require so 

 much the greater care in preparing the soil, in order to 

 ensure their healthy growth. The pressm^e of a layer 

 of earth half to one inch thick suffices to prevent the 

 developement of the seed sown in the ground. Such 

 seeds require only just as much earth to cover them as 

 wiU retain the needful moisture for germination. It is, 

 therefore, found advantageous to sow clover together 

 with corn of some kind ; for as the com is earher and 

 quicker in growth, its leaves shade the young clover 



