72 VEGETABLE FORCING 



manure must be well decayed so that it will be short and 

 fine before the soil is used for forcing purposes. (2) The 

 fiber must be thoroughly mixed with or incorporated 

 throughout the mass of soil. (3) The soil must be thor- 

 oughly saturated with the liquid of the manure. To 

 accomplish these results it is necessary to start compost- 

 ing well in advance of the time when the soil will be 

 wanted for use in the greenhouse. The actual length of 

 time required to make a good compost depends upon the 

 character of the soil as well as upon the manure. If the 

 soil is heavy and the manure fresh and coarse, much 

 more time will be needed than if the soil is light and the 

 manure old and of fine texture. The time required for 

 composting also depends upon the method employed. 



One of the oldest and most satisfactory methods is to 

 stack manure and sods in alternate layers. The piles are 

 generally 4 or 5 feet deep and large enough to meet the 

 needs of the house. Thick, heavy clover and grass sods 

 are preferable. They may be cut with spades and hoes, 

 or more rapidly with a plow set to run very shallow, and 

 then cut across the thin furrow slices with a spade or an 

 old axe. The sods and manure are hauled and stacked 

 as near to the greenhouse as possible, so that the com- 

 posted materials may be placed in the greenhouse with- 

 out further hauling or unnecessary handling. The 

 relative thickness of the alternate layers of manure and 

 compost should be determined mainly by the character 

 of the soil used. More manure is needed for the heavier 

 soils than for the lighter types. When the sods are 

 grown in silt and clay soils, the layers of manure and 

 sods should be of about equal thickness, and they may 

 range from 10 to 15 inches. 



In sandy soils the layers of manure may be several 

 inches less in thickness than the sods; 10 inches of 

 manure and 14 inches of soil give excellent results. 

 Compost piles of this character should be started at least 



