384 Plant Physiology 



advantages outweighing all other considerations of special 

 habitat. 



In the United States alfalfa seed mature well only in the 

 dry climate of states like Colorado and Utah. In the 

 South the potato matures so early that a long season of 

 storage, resulting in probable injury, would be required if 

 home-grown tubers were used in planting. 



Some growers have expressed the opinion that there 

 is a marked physiological change more or less gradually 

 developed in strains of onions or radishes repeatedly grown 

 in certain sections of California. It is not possible at pres- 

 ent to determine if other factors have been overlooked, 

 but at any rate it is believed that seed from radishes which 

 have been grown for successive years in California will, 

 when planted in other sections of the country alongside of 

 the home-grown or recently imported seed of the same strain, 

 show clearly that the far western-grown product has under- 

 gone some marked change with respect to eastern conditions. 



Similarly, onions grown from California seed are said 

 to be different in keeping quality from those bulbs grown 

 from seed produced in Michigan. This effect is said to 

 assert itself even when the most stringent methods of 

 selection are practiced. There is grave doubt if this is a 

 general rule, and we may well believe that varieties may 

 be developed which will not show this tendency. 



The seed of cabbage, cauliflower, and some other crucifers 

 were first grown extensively in this country upon Long 

 Island, and the region became famous for the production 

 of these crops. More recently it has been found that a 

 similar favorable locality is the Puget Sound region. 

 Growers are so sure of the wholesome effects of these 



