OTHER LEGUMINOUS PLANTS. I3I 



growth in these. With the large varieties it is some- 

 times possible to grow twenty tons per acre, but the 

 average will be much less than that amount. 



Distribulion. — The northerly limit of successful 

 growth in the cowpea would seem to be the southerly 

 limit of successful growth in the common field pea. 

 The line which forms this border-land of high devel- 

 opment will run irregularly across the continent, but 

 it is not far distant from the fortieth, parallel. The 

 cowpea has been grown in the northern areas of 

 Nebraska, Iowa, Illinois, Indiana and Ohio and even 

 in Connecticut, but in these localities the aim is rather 

 to grow it as a soil renovator and to a less extent as 

 a soiling food than as a grain crop. In the southern 

 half of the states named, Connecticut excepted, it is 

 grown by many farmers, but the most favorable 

 conditions for completest development in the large 

 varieties is found further to the southward, as far 

 south probably as the latitude of St. Louis in Mis- 

 souri, that is to say, south of the thirty-eighth parallel 



In the warm valleys of the Rocky mountains 

 the cowpea will doubtless grow vigorously under 

 irrigation, but it is not likely to come into general 

 favor in these areas, because of the presence of alfalfa 

 in so great abundance, and yet in the more southerly 

 of these valleys, it may come to be grown extensively 

 to provide a grain eminently suited to, the finishing 

 of pork reared upon alfalfa. \Mien thus grown, 

 swine could be made to harvest the crop where it 

 grew. But in these valleys it is not at all probable 

 that the cowpea will soon be produced as a soiling 

 food. In Canada and m the states bordering on 

 that country, any variety of the cowpea that has been 



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