26 GARDEN FARMING 



extensively employed with great success. This contrivance consists 

 of a large metal pan 4 to 6 feet in width, 8 to I o feet in length, and 

 about 6 inches deep, fitted at one end with connection for a steam 

 hose. This pan is inverted over the surface of the soil area to be 

 sterilized, the sides are well banked, and the steam is admitted 

 under pressure. The hot steam fills the space under the inverted 

 pan and penetrates the soil, effectively sterilizing it for seed-bed 

 or greenhouse use. 



The advantages of sterilization, as have already been noted, are 

 the destruction of nematodes, more or less complete destruction of 

 spores of fungi of various kinds, and the liberation of plant food. 

 From observations which have been made it is believed that if 

 sterilization gave no protection from enemies or diseases, the oper- 

 ation would still be justified and prove economical because of the 

 increased growth of plants in such soils over that in ordinary 

 compost. 



From what has been stated it will be noted that the soil must be 

 considered, from its mechanical relation to the plant, as a mechan- 

 ical support for the plant, as a carrier of moisture and air, and 

 as a conveyer of plant food. Fortunately for the gardener the soil 

 under outdoor conditions is more easily modified than any other 

 single factor entering into the environment of the plant. Heat, 

 sunshine, wind currents, and moisture are less easily modified than 

 are the soil conditions. In fact, moisture conditions are the only 

 other factor over which man has any direct control. Through irri- 

 gation we can influence the moisture supply of plants ; by the use 

 of fertilizers, the turning under of green crops, the use of lime and 

 proper cultivation, we can greatly modify soil conditions. The soil 

 is one of the most complicated factors with which we have to deal, 

 yet it is one which, from a market gardener's standpoint, can be. 

 most satisfactorily changed. 



Transportation facilities, water supply, congenial climate, and 

 sufficient labor are of more importance to the market gardener 

 than the soil ; for he can, through the use of artificial means already 

 mentioned, modify the soil to meet the requirements of any special 

 crop with which he may be dealing, provided, of course, it is true 

 soil. In general agriculture the composition and fertility of the soil 

 is of greater importance than in market gardening or floriculture. 



