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The Cornell Reading Courses 



SOIL REQUIREMENTS FOR ALFALFA 



The best alfalfa soils are medium to heavy in texture, with porous 



subsoil. At one time it was thought that alfalfa was adapted only to 



deep soils with porous subsoil, so that the roots might penetrate easily 



to a depth of several feet; at present, however, alfalfa is grown in every 



State, on practically every type of productive soil except those that are 



acid. On very heavy soils or on those with a hardpan subsoil, while alfalfa 



often will grow very well, it is much more likely to winterkill; and on 



some of the hardpan soils of New York, alfalfa culture is uncertain because 



of winterkilling. 



Tile drainage on these heavy soils not only improves the yield, but also 



increases the ability to withstand winter freezing. In fact, alfalfa wdll 



winterkill on even the best 



land if it is not properly 



drained. It is particularly 



sensitive to standing water 



during the winter months. 



In general, the water table 



should be not nearer than 



two feet from the surface for 



more than a few days at a 



time, and is better at about 



four feet below the surface. 



The root system of alfalfa varies with soil conditions. 



In a porous soil, easy 'to penetrate, the taproot will 



extend almost straight downward for from lo to 20 



feet, or until the water table is reached. However, if a 



stratum of hard soil is encountered, the taproot will 



break up into a much-branched root system. In a 



very compact soil the roots may not penetrate more 



,. r , ■ '^""1 than s or 4 feet, even when the plants are several 

 Hon of roots ma deep o -^ t t- 



porous soil, and in a years old. 



compact soil. In Lime 



Field and forage crops vary in their requirements 



Redtop and 



Fig. 



147. -;- Distribu- 



soil. In 

 the first case a long 

 taproot is developed, 



while in the second ^ ,. , . , , . ,, ., 



case the aproot ^t lime or basic substances m the soil. 



breaks up into many alsike clover will tolerate some acid in the soil, while 

 many of the most important field crops, such as 

 oats and buckwheat, seem to be quite indifferent to the presence of lime 

 so long as the soil is not acid. Certain crops, notedly red clover and 

 alfalfa, are very sensitive to the lack of lime. In order to grow alfalfa, 

 lime must be applied to at least three-fourths of the cultivated soils of 

 New York. 



