FORAGE CROPS. 15 



serves to st-attei- the seed of the pest. The common system of farm- 

 incr consists of takinjj^ a cro]) of wheat ev(>rv alternate year. Icavinjr 

 the hmd idle every other year. During the idle year the land is sum- 

 mer fallowed: that is. plowed up in spring and left bare during sum- 

 mer. These fallow fields often furnish excellent wild-oat pastures, 

 which are generally utilized. 



At the present time alfalfa, clover, and brome hay are hcginning 

 to take the place of grain hav in this wheat-growing section. It has 

 been learned that an exhausted ))rome-grass tield can l)e restored to its 

 earl}' vigor by plowing in winter and harrowing to good tilth. After 

 this plowing, a crop of spring grain may be taken without serious 

 injur}' to the brome grass. 



FORAGE CROPS. 



Ai.FALFA" {MfHlicago mtlvu). 



(5ENEKAL CONDITIONS. 



This well-known forage plant is extensively gi'own throughout the 

 West in all localities wliere the conditions are suitable. It rctjuircs a 

 well-drained soil and a fairly good supply of water, l»ut will not endure 

 an excess of water (standing water) near the surface. It thrives best 

 where the summers are hot and dry and the winters not too cold. It 

 will withstand a moderate amount of alkali in the soil. In the North 

 it suffers in some localities from the effects of too cold w inters, and is 

 not usually successful above an altitude of 5,000 or 0,000 feet. It can 

 be grown without irrigation in l)ut comparatively few localities in the 

 Northwest; but under irrigation it is extensively grown in all the 

 States of this region, and reaches its greatest perfect ion in the hot, dry 

 valleys of California, where the summer season is long, the water sup- 

 ply abundant, and the soil well drained. Alfalfa will not succeed on 

 acid soils, but these are of rare occurrence in the western part of the 

 United States. 



Alfalfa is a perennial leguminous plant, a native of western Asia, 

 but cultivated in the Old World for ages. Jt was brought to Mexico 

 by the Spaniards and from there spread into South America and north 

 along the Pacific coast, and then throughout the interior arid and semi- 

 arid regions. The name alfalfa, of Arabic origin, was given by the 

 Spaniards and is in common use throughout western America. In 

 Europe the same plant is known as lucern, a name which is common in 

 the eastern United States, and also in Utah and the adjacent parts of 

 Idaho and Wyoming. In the latter region the name is commonly pro- 

 nounced with the accent on the first syllable. 



«For further description see Farmers' Bulletin No. 31. 



