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CONDITIONS AFFECTING SUCCESS WITH ALFALFA. 



1. Climate and Soil. Alfalfa is naturally adapted to a warm 

 climate ; in deep soils it is highly drought resistant, but is also well 

 adapted to irrigation. In general it does not endure very severe 

 winters and an excess of rainfall or irrigation is decidedly inju- 

 rious. Regardless of its nature the soil must be well drained or 

 the crop will fail, as alfalfa is a plant which cannot stand "wet 

 feet." 



It succeeds best on a neutral soil, and will adapt itself to an 

 alkaline soil, but is an absolute failure where there is more or less 

 acidity or "sourness.'' A clean, deep and well drained, light, 

 loamy soil is best, but heavy clay soils may be so modified as to 

 yield profitable crops, provided they are not permitted to become 

 water-logged and sour. Calcareous soils in humid regions are 

 very good, and even the chocolate colored river bottoms and 

 maize and oat lands are well adapted to alfalfa. 



Another essential for success with alfalfa is the presence of 

 specific nitrifying bacteria in the soil and a fair amount of humus, 

 since humus is necessary for the best growth of bacteria and the 

 plants can not do well without their presence. The lack of these 

 bacteria in the soils of the Eastern States in the early days has 

 proved to be the principal source of failure of alfalfa or rather 

 lucerne as it was then called. 



2. Treatment of the Soil. Alfalfa is not stoloniferous and 

 poliferation is so very rare that it practically cannot spread, and 

 especially when young is unable to choke out other plants as do 

 the grasses. It is therefore very essential not only to plow deeply 

 in order to allow the long roots to penetrate deeply, but also to 

 cultivate in such a way that the land will be practically free from 

 w^eed seeds and in very good tilth before the seeds are sown. 



If the land is lacking in lime, it should be applied before plow- 

 ing at the rate of from one-half to one ton of burned lime, or 

 twice as much ground limestone per acre. During the plowing 

 the lime will then become thoroughly mixed with the soil and 

 will therefore be more efficient. It is well also to add manure 

 before planting and mix it thoroughly with the soil. 



If the land is virgin to alfalfa or has not become thoroughly 

 inoculated it is well also to add at this time about one-half ton of 

 soil from a field known to produce good alfalfa plants whose 

 roots are abundantly supplied with nodules. If such soil is not 

 conveniently available, "canned bacteria" or "nitragin" (pure 

 nitrifying bacteria ) may be used instead. 



A one-pound can of "nitragin" as put on the market commer- 

 cially is sufficient to inoculate one acre. In purchasing nitragin, 

 care should be taken to ask for "nitragin for alfalfa," as the 

 varieties of this material are specific, and a variety for cow peas 

 wall not do for alfalfa. 



Most of our soils in Hawaii are fortunatelv already inoculated 



