LEGUMINOUS PLANTS. I09 



grown until mature on a piece of land and then har 

 vested, the land will contain more nitrogen than 

 before the peas were sown on it. It is evident, there- 

 fore, that the pea should be grown with an eye to 

 preparing the land for a crop that requires much 

 nitrogen, as, for instance, a crop of wheat or other 

 cereal, or a crop of corn. It is also evident that it can 

 be grown successfully on soils lower in plant food 

 than would suffice to produce a maximum crop of any 

 one of the cereals, at least so far as concerns the pres- 

 ence of nitrogen in the soil. If the ground is prop- 

 erly prepared it may be successfully grown on land 

 that is foul with certain forms of weed life, as, for 

 instance, annuals. But peas should not be grown 

 on land infested with certain perennials, such as the 

 Canada thistle. 



Theoretically, peas should not be sown on over- 

 turned sod. It is commonly considered better prac- 

 tice to give these lands up to other grain crops, as 

 oats, because of the abundance of the vegetable mat- 

 ter which they contain. Notwithstanding, peas 

 grow handsomely on such land, the other conditions 

 being right, owing probably to the moisture which 

 is held for the peas by the grass roots as they decay, 

 and they put sod lands in excellent condition for 

 being followed with a cereal crop. Peas may be 

 succeeded with much advantage if grown alone by 

 winter wheat or rye, where the former can with- 

 stand the rigors of the winter. When followed by 

 one or the other of these crops, the land requires 

 only to be disked in preparing it, unless the soil 

 should be foul with weed life. 



Soil. — The best soil for peas is a mild, porous 

 and moist clay loam, free from superfluous water 



