68 DEPARTMENTAL REPORTS. 



sort now grown is the smooth Cayenne, which is an excellent variety 

 in almost every resjject except that it is tender and subject to disease. 

 The investigation of the alkali-resistant crops will be continued in 

 cooperation with the Bureau of Soils, a special effort being made to 

 obtain facts relative to the alkali resistance of different forms and to 

 introduce new and promising forms from foreign countries. In the 

 cereal work special attention will be given to encouraging the use of 

 macaroni wheat by factories. Further studies will be made of the 

 winter wheats with a view to extending their areas into regions where 

 they have not been tested heretofore. The plans in connection with 

 the work on nitrifying organisms in the Pacific coast and Mississippi 

 Valley laboratories, etc., have been fully covered in the items given 

 under work of the year, so that it is not necessarj'' to repeat the state- 

 ments here. 



BOTANICAL INVESTIGATIONS AND EXPERIMENTS. 



During the year the investigations of this branch of the Bureau 

 have been pushed with the usual activity. The work of the Botanist, 

 Mr. Frederick V. Coville, is largelj" administrative, but time has been 

 found for continued investigations in geographic botany and aborigi- 

 nal botany. The following is an outline of some of the more impor- 

 tant lines of investigation : 



SEED LABORATORY. 



During the year there were tested in the seed laboratory 2,209 sam- 

 ples of seed, the larger part for both purity and vitality. There have 

 been 1,544 accessions to the seed herbarium. Successful studies have 

 been made on the germination of the more difficult grass seeds, such 

 as Johnson grass, Bermuda grass, and Kentuckj^ bluegrass. A com- 

 parative study of the seeds of rescue grass and chess, with drawings 

 and descriptions, has been made. A comparative study of the seeds 

 of Poa, which are of importance, has also been made. The field work 

 of this branch of botanical investigations has been mainly in the line 

 of that outlined last j^ear. Studies on the harvesting, curing, and 

 cleaning of Kentucky bluegrass seed has been continued. The field 

 work was done in June of 1901, and the samples tested and results 

 written up during the year 1901-2. Further observations on the 

 harvesting of Kentuckj^ bluegrass seed in Illinois, Missouri, and Iowa 

 were made during June, 1902. Comparative experiments in red clovers 

 of different origin were carried on by a number of experiment stations 

 in cooperation with the laborator3\ These experiments have shown 

 that the European forms will not endure the hot sun as well and are 

 not as early as our United States forms. The European forms have 

 much more delicate stems than the United States forms and are almost 

 entirely smooth, while the United States forms are very hair}'. Obser- 

 vations of soil temperatures and continuous sowing of a variety of 

 seeds have been carried on, the object being to determine the effect 

 of alternating temperatures of the upper stratum of soil on the germi- 

 nation of seed. Soil temperatures were taken at eight different depths, 

 varj'ing from one-fourth inch to 2 feet, as well as the air temperature 

 and solar radiation temperature. These observations were taken at 

 intervals of fifteen minutes from one-half hour before sunrise until 10 

 p. m., from March 26 to July 1. Plantings of twenty varieties of vege- 

 table and forage-plant seeds were made at intervals of two or three 

 days during the entire period. The results of this work will show the 



