XXVI REPORT OF THE SECRETARY OF AGRICULTURE. 



the past few years in the West has brought about a much better 

 understanding of some of the important questions concerning the 

 agricultural development of that region. Other important lines of 

 work in the matter of plant breeding have to do with cereal improve- 

 ment, but these will be more fully discussed under " Introduction of 

 seeds and plants.' 1 



NITROGEN-GATHERING BACTERIA. 



Nitrogen is one of the most costly and probably the most important 

 of all plant foods. So valuable is this material and such is the demand 

 for it that already it has been predicted that it is only a question of 

 a f eAv years until the commercial supply will be exhausted. Recentty, 

 however, attention has been turned to the bacteria which develop 

 nitrogen in connection with the roots of clover, beans, and many 

 related crops. A new method of cultivating and obtaining these 

 organisms in large quantities for distribution with leguminous seeds 

 has been discovered, and will be perfected and put into practical use 

 during the coming year. This, it is believed, will make it practicable 

 to grow many leguminous crops where, owing to the lack of proper 

 organisms, they have refused to grow in the past. It will also make 

 practicable the use of a large number of legumes for gathering 

 nitrogen. 



BOTANICAL INVESTIGATIONS AND EXPERIMENTS. 



The botanical investigations and experiments conducted by the 

 Department have led to many valuable discoveries, and from year to 

 year their great practical value is being recognized more and more. 

 The work being done on seeds,^ improvement of crops and methods of 

 crop production in our tropical possessions, and prevention of the great 

 losses of cattle in the West through the eating of poisonous plants is 

 of special interest. The following are some of the more striking 

 results of the work done under this head during the past }^ear: 



NEW FACTS CONCERNING KENTUCKY BLUE-GRASS SEED. 



The Department of Agriculture has for a number of years past pur- 

 chased considerable quantities of Kentucky blue-grass seed for Con- 

 gressional distribution. Since the practice was inaugurated of making 

 germination tests of all the seeds distributed it has been found that 

 Kentucky blue-grass seed, as offered in the open market, could not be 

 secured ordinarily of a higher germination than 50 to 60 per cent. 

 On the other hand, it was found possible, by special purchase, to 

 secure seed showing a germination of 90 per cent and more. These 

 facts suggested an investigation of the causes of the low germination 

 of ordinary commercial samples. It has been found that in harvest- 

 ing this seed the tops of the grass are stripped from the growing plants 



