LEGUMINOUS PLANTS. I3I 



Nebraska, Wyoming, Idaho and Oregon, till it 

 reaches the Cascade mountains. It would then turn 

 south to the northern boundary of California, which 

 it would follow to the ocean. In some favored val- 

 leys this plant can be grown north of the line thus 

 drawn, and on many elevations south of that line it 

 cannot be successfully grown. But it will probably 

 be found that north of that line the common field pea 

 can better be made to serve any ends sought by 

 growing the cowpea, and vice versa. But beyond 

 all question the limit of the successful production 

 of the cowpea will be extended further to the north 

 in the near future. Providence is good, nature is 

 accommodating and man is wise. By a careful 

 choice of varieties, coupled with rigid selection of 

 the early maturing seeds from vigorous plants, it 

 will be found that the line of successful growth of 

 cowpeas will be pushed much further to the north, 

 as has been done in growing Indian corn. Within 

 the past three months and since the above was for- 

 warded for publication, cowpeas of the Early Black 

 variety have been grown for pasture and grazed 

 off by sheep with much success at the Minnesota 

 University experiment farm, as seen in Figure i8. 



Place in the Rotation. — The cowpea being a 

 legume should be made to follow a crop that had 

 drawn heavily on the nitrogen in the soil, as, for 

 instance, a crop of grain or corn. And since it is 

 a soil renovator it ought to be followed by some such 

 crop as cotton, or corn, or sugar cane. And since 

 in the south, where there is a long season for growth, 

 the cowpea can be grown as a catch crop, it may be 

 made to follow such winter crops as rye, rape, 

 vetches or oats, and it may also be made to come 



