Ill 



usually derived from some peculiai ity of the plant. This is also true of 

 other plants. It is said that all the varieties of the sugar-beet may be 

 classed in four groups ; there seem to be twenty-three principal varie- 

 ties, which have several hundred names. 



The varieties of sorghum often can not be distinguished by the ap- 

 pearance of the seed alone, or even by the seed-heads alone. They 

 can best be classed by observing the growing canes. Varieties which 

 have long been grown under very different conditions often vary enough 

 from the usual type to be classed as subvarieties. The Chinese cane 

 from Australia differs in some respects from the Chinese from Central 

 America, and that differs in some respects from the Chinese of this 

 country. 



These facts add to the difficulty of classifying the numerous varieties 

 of sorghum. Sorghum is also grown in opposite hemispheres, and the 

 proper season to collect varieties in one country is not the proper sea- 

 son in another couutiy. 



ACCLIMATIZATION OF VARIETIES. 



Iii growing and comparing varieties of sorghum which have been 

 obtained from different localities it is necessary to consider acclimati- 

 zation. Plants, as well as men and animals, require time to adjust them- 

 selves to new conditions. Linureus said seed from tobacco grown in 

 Sweden ripened a month earlier than that from foreign seed. Seed corn 

 taken from Virginia to New England ripens with difficulty the first 

 season. Seed corn taken from New England to latitude 45 ripens with 

 difficulty the first season. In both cases they mature perfectly in their 

 new homes after a few seasons- European plants produced in India, 

 from sxieds grown in India a few seasons, succeed bettor than from 

 directly imported seeds. 



These facts indicate that it is necessary to acclimate varieties of sor- 

 ghum procured from localities which have different conditions of soil 

 and climate before correct comparisons of their qualities can be made. 



In the experimental work at this station it was especially noticeable 

 that varieties of sorghum received from localities having long and warm 

 growing seasons produced larger canes, which matured later than the 

 same varieties from Northern localities. It was also noticeable that 

 varieties received from localities which have little rain fall succeeded 

 better this season than the same varieties received from localities hav- 

 ing excessive rain-fall. 



It is obvious that a plant may be removed many thousand miles with 

 slight change of environment and that it may be easily acclimated. 

 It is also obvious that a plant may be removed a comparatively short 

 distance with considerable change of conditions and may be acclimated 

 with difficulty. It seems to require three years to acclimate varieties 

 of sorghum which have been grown under very different conditions. 

 These facts require consideration when making selections from numer- 

 ous varieties grown the first time in this country. 



