42 VEGETABLE GARDENING 



melons and cucumbers without stable manure shipped 

 from Philadelphia and New York. 



76. Manure as a source of humus. — Many growers of 

 vegetables would never buy manure were it not for the 

 necessity of maintaining the supply of soil hurrius. That 

 is, it would be cheaper for thousands of gardeners to pur- 

 chase commercial fertilizers for the needed plant foods 

 than to buy bulky manure, pay freight and then haul 

 several miles perhaps, not to mention the cost of spread- 

 ing and of composting. But a liberal supply of soil humus 

 is absolutely essential to success in growing all classes 

 of vegetables. It increases the water-retaining capacity 

 of soils ; secures improved soil aeration ; aids important 

 chemical changes ; increases soil temperature ; helps to 

 create favorable conditions for the work of friendly bac- 

 teria ; improves the structure of soils ; makes it possible to 

 begin work earlier in the spring and reduces the labor of 

 tillage. Stable manures are superior to green manures 

 as humus-making materials because they decompose more 

 rapidly and are, therefore, of greater value to the crops 

 under cultivation. 



77. Manure as a source of plant food. — In many in- 

 stances manure is the cheapest source of plant food. 

 Gardeners living near the cities often procure it at nomi- 

 nal prices. Under such conditions it would be unwise to 

 make large expenditures for commercial fertilizers unless 

 for special foods, such as nitrate of soda. Stable manures 

 do not become available so quickly as many forms of 

 commercial fertilizers, although composting (86) is of 

 great value in hastening decomposition. The following 

 table (U. S. Department of Agriculture, Farmers' Bulle- 

 tin 192, page 9) shows the relative composition and the 

 value of the manure of various animals : 



