VEGETABLE GARDENING, OR OLERICULTURE 9 



manure they frequently use from 500 to 2000 pounds of high-grade 

 fertilizer to the acre, in order to produce in a single season the 

 three or four remunerative crops above referred to. There are no 

 soils which are naturally sufficiently fertile to produce paying crops 

 under such an intensive system as holds in market gardening or 

 truck farming. In fact, not even the richest soils in the United 

 States are capable of producing crops sufficiently large to warrant 

 a grower's carrying on such a system without the use of stable 

 manure, green manures, and fertilizers combined. In many locali- 

 ties it is impossible to secure an adequate quantity of stable 

 manure, but when it can be secured, even if it has to be shipped 

 from a distance by car or boat, it will be advantageous and profit- 

 able. By the use of large quantities of stable manure and by 

 plowing under heavy crops of cowpeas or other legumes, the me- 

 chanical character of the soil, as well as its fertility, can be changed 

 to a marked degree. Heavy retentive soils can be lightened and 

 made " earlier." The drainage can be improved by tilling and by 

 subsoiling, and the seed bed constantly made deeper until a depth 

 of 10 or 12 inches has been reached, which is sufficient for most 

 market-garden crops. 



One of the secrets to success in market-garden and truck work 

 is to be able to anticipate the demands of the market, and to have 

 a large and sufficiently early supply of vegetables to meet these 

 demands. This depends more upon the ability of the man to 

 manage his business than upon the fertility of the soil or the 

 method of cultivation practiced. 



Plant diseases and insect enemies. In order to appreciate fully 

 the action of insect enemies and plant diseases, as well as to deter- 

 mine the influence of fertilizers and the moisture supply upon 

 growing plants, a brief sketch of the structure and function of 

 various parts of the plants becomes necessary. Plants are made up 

 of three distinct parts, two above ground and one usually beneath 

 the soil. These parts we recognize under the names " root," 

 "stem," and "leaf." Each one bears a definite relation to the 

 others, both as regards its arrangement and its functions. 



Root. The function of the root is first mechanical, then physio- 

 logical. The mechanical function is to give anchorage to the plant 

 and to support the stem which carries the leaves. The physiological 



