97 



this water table, by capillary action, during the summer 

 months, moisture is being constantly drawn upward, 

 through the porous soil, to the surface, where it passes 

 away, partly through growing plants and partly by evapo- 

 ration from the surface soil. It is this so-called capillary 

 moisture which plants require in abundance. Many soils 

 need thorough tile drainage to render them fertile. An 

 excess of water should rapidly drain away. Likewise in a 

 dry season all good land should be irrigated to maintain 

 its fertility. Crops fail in a drought not only because they 

 do not find sufficient moisture to appropriate, but also be- 

 cause, since water is the great solvent and conveyer of 

 food to the roots, its absence means starvation to the 

 plants. 



TILLAGE. 



Tillage is another active agency for the promotion of 

 fertility. We do not plough, and harrow, and cultivate, 

 and hoe, merely and solely to kill weeds, necessary as it is 

 to destroy the robber plants which spring up and threaten 

 the cultivated crops. Tillage is of powerful assistance in 

 rendering the soil productive and fertile. The operation 

 breaks up and disintegrates the soil particles, admits the 

 oxygen, and thereby chemical changes are induced and the 

 elements of plant nutrition are made available for use by 

 the crops. 



Under the old system of fallows, each field, at regular 

 intervals of time, was allowed to rest for a season to recu- 

 perate its strength. No crop was grown upon the fallow 

 field, but it was continually cultivated, and kept loose and 

 mellow, so that much inert plant food was brought out and 

 made available for the use of the ci'ops which followed in 

 the rotation. This old-time practice, while not advisable 

 for us to follow to-day, yet demonstrated how much of 

 plant food and fertility lies latent and becomes slowly 



