BUREAU OF PLANT INDUSTRY. 141 



in this crop and a consequently larg'er acreage. Field work with 

 soy beans has been extended, especially in connection Avith the testing 

 of improved varieties selected from numerous introductions from 

 Asia. Much hybridization has been done, involving the crossing of 

 the nonshattering smooth sort with standard commercial sorts. 



Many of the most important varieties now grown are the result 

 of the department's work and include several that have been recently 

 distributed, vjz, the Haberlandt, Virginia, Wilson-Five, Hahto, 

 Biloxi, Black Eyebrow, Manchu, and Peking. The testing of varie- 

 ties for food purposes has given a soft-boiling bean superior to any 

 other tested. The Hahto is a variety especially valuable for use as 

 a green vegetable. Breeding work is being continued with varieties 

 of high oil and protein content and high forage and seed yield. 



SORGHUM BREEDING. 



Possibilities in the development of improved varieties of sorghum 

 by breeding are clearly indicated. Owing to the great importance 

 of this group of forage plants, especially to dry-land agriculture, 

 particular efforts are being made to develop varieties that will be 

 adapted to the wide range of conditions found in the Great Plains 

 region. 



BREEDING RUST-RESISTANT ASPARAGUS. 



As a result of the substitution of resistant asparagus for the sus- 

 ceptible strains previously gi'own, the rust is rapidly being elim- 

 inated. The distribution of the improved strains has been extended 

 to every asparagus-growing section in the country, including many 

 commercial seed growers and State experiment stations. Early 

 and late strains to suit different growers who wish to meet different 

 market conditions have been developed. 



INVESTIGATIONS OF THE QUALITY OF SEED. 



EXAMINATION OF SEED SAMPLES. 



During the year 16,838 samples of seed were received for test at the 

 Washington laboratory and 11,349 at the five branch laboratories 

 maintained in cooperation with State institutions. This is a some- 

 what larger number of samples than was tested in the previous year. 



In the spring of 1918 seed of red clover and redtop was collected 

 for examination for the presence of adulterants as well as to deter- 

 mine how fully the seed trade is complying with its agreement to 

 label all field seeds with the percentage of pure live seed. This ma- 

 terial will be examined and reported on later. 



The enforcement of the seed-importation act has kept out of the 

 country much forage-plant seed of poor quality, over 400,000 pounds 

 of red-clover seed having been prohibited entry during the month 

 of May, 1918. On account of the difficulties of trans-Atlantic ship- 

 ment, imports of most kinds of seeds have fallen off, Canada blue- 

 grass from Canada and winter rape from Japan being the only 

 two items the imports of which have exceeded those of the previous 

 year. 



GOOD SEED OF IMPROVED WHEAT VARIETIES. 



Interest increases in obtaining quality seed of productive varieties. 

 Inspection of growing fields of such varieties has been accomplished 



