LIME 389 



usually destroy the plants. In arid regions, where the plants are 

 free from winter killing and the ordinary fungous diseases that 

 cause root rot, alfalfa plants are very long lived. 



Pollination. It has long been known that alfalfa produces 

 flowers more freely in dry, sunshiny climates than in humid regions. 

 In northeastern United States very few flowers are produced, espe- 

 cially on the first crop, when the weather is likely to be humid. It 

 is very seldom that a seed crop is produced in this section. In the 

 drier regions there is usually no difficulty in securing a seed crop, and 

 this seems to be due to the fact that plants flower much more 

 abundantly, and natural facilities to secure pollination are better. 



In alfalfa the stigma and anthers are tightly held in the lower part 

 of the flower. Unless they are freed by <e tripping/' fertilization 

 will not take place. This can be demonstrated by taking mature 

 alfalfa flowers and touching the inside of the flower with a fine- 

 pointed pencil or toothpick. Under field conditions, it is probable 

 that insects do most of the tripping. It has also been observed that 

 the flowers will trip naturally in dry weather under bright sunshine. 



Soils for Alfalfa. While it is generally supposed that alfalfas 

 prefer a loose, pervious soil, due to the deep root system, it is never- 

 theless found growing very successfully on some of the heaviest 

 gumbo clays. If fertility and moisture are available, the texture 

 tof soil does not seem to be important. 



Drainage is very important, as alfalfa will not live on wet land 

 or land where the water table comes to the surface at any time during 

 the year. The water table must be kept at least two feet, and better 

 three to four feet, below the surface. 



Alfalfa also requires a very fertile soil. While most of the clovers 

 can be started in poor soil and are recommended as a crop to build up 

 poor soils, this is not true of alfalfa. In general, land that would not 

 produce twenty-five bushels of wheat or forty bushels of shelled corn 

 in a fair season is not suitable for growing alfalfa until it has been 

 manured or fertilized. 



Lime. Sufficient lime in the soil is also very important. The 

 lack of lime is one of the principal reasons why alfalfa culture has 



