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in a great variety of ways and its food value ranks 

 very high. It likewise plays an important part in 

 the necessary crop rotation schemes of the gardener 

 on account of the fact that it belongs to the legumi- 

 nous group of plants, now known to have the power 

 of fixing the free nitrogen of the air in a form avail- 

 able for plant growth and thereby of great value to 

 all cultivators of the soil. 



The pea is classified in various ways, but perhaps 

 the most important grouping is that depending upon 

 the nature of the seed. From this standpoint the 

 pea is divided into three groups or types. First, 

 including all those varieties with smooth, hard seed ; 

 second, those with green and wrinkled seeds; and, 

 third, those with thick fleshy pods and small seeds. 

 The latter are cooked and used in the same way as 

 string beans. 



The first group includes most of the extra early 

 varieties. They excel in hardiness and are very resist- 

 ant to frosts. This group comprises a number of 

 the most important commercial varieties. The 

 second or wrinkled group is less hardy, more likely 

 to be injured by frosts and is not well adapted to 

 field conditions. Its cultivation is confined al- 

 most entirely to home and market gardens. The 

 third group, or sweet peas, is grown only in a 

 limited way and is adapted only to garden culture. 

 Peas are also classified as dwarf, half dwarf and 

 tall, depending upon their habits of growth. They 

 are likewise classified into early, medium and late 

 varieties, depending upon their time of maturity. 

 This classification is carried through the other groups. 



Peas are especially well adapted to the cool days 

 of spring. This fact, together with the compara- 

 tively short season required to mature them to a 



