956 FORAGE CROPS 
shape and form. The period of mature growth 
also varies, the varieties ranging in time of 
maturity from two to six months, although the 
habit of plant bears some relation to the period, 
for the more nearly the plant approaches the bush 
form, the shorter the time required for maturity. 
In order to choose the proper variety, the object 
of its cultivation should be clearly established. 
When short, quick growth and maturity are re- 
quired, then the bush varieties should be chosen, 
particularly in the North; whereas, if the purpose 
is to produce much forage and the period of growth 
can be extended, the vining varieties are likely to 
be more useful. When grown primarily for green 
forage, the period in which they must grow should 
determine the variety. It is more difficult to choose 
varieties for the North than for the South, as the 
plant has not been so carefully studied in this sec- 
tion. In the more northern sections, the Early 
Black, Small Black, Black Eye, Mt. Olive, South- 
down, Red Ripper, Whippoorwill, Wonderful, Clay, 
New Era, and Iron have proved excellent for the 
various purposes for which cowpeas are grown. 
Early Black, Black Eye, New Era and Mt. Olive 
are superior when the seed crop is desired, as they 
mature quickly; the others are better adapted for 
forage and green manure. The cowpea varies so 
widely in its habits of growth that it is possible to 
select varieties suitable to all conditions. 
