l6 MAKING HORTICULTURE PAY 



When the humus is exhausted the physical con- 

 dition of the soil suffers. The soil becomes more 

 impacted, less easily aerated, and less easily pene- 

 trated by the roots of plants. Some soils so light 

 as to lift with the wind can be kept from blowing, 

 at least in a great measure by simply keeping them 

 stored with grass roots or other vegetable matter 

 buried in the soil. The increase in the power of 

 soils to hold moisture is very great when well stored 

 with humus. When commercial fertilizers are 

 sown on land they will fail to respond properly 

 unless the land is supplied with humus. 



Such being the case, every effort should be made 

 to store the soil with humus. It would not be impos- 

 sible to have excess of humus, but in practice this 

 seldom happens. Humus may be put into the soil 

 in the form of clover roots and of grass roots, of 

 buried catch crops and barnyard manure. 



