836 WEED FLORA OF IOWA 



In reports of more recent work, A. F. Woods found dodder seed 

 frequent in alfalfa and red clover seed. The adulteration and mis- 

 branding of alfalfa, red clover and grain seeds was discussed by 

 W. A. Taylor and B. T. Galloway. F. H. Hillman in several papers 

 on the impurities, adulteration, etc., of clover and forage plant 

 seeds and vetches, presented admirable figures and good descrip- 

 tions of weed seeds found as impurities. Westgate, McKee, Evans, 

 and Vinall gave a brief account of impurities found in alfalfa seed 

 and sweet clover. The subject of low grade clover seed was con- 

 sidered by Edgar Brown and Miss Crosby. 



In a paper by Brown and Hillman, "The Seed of Red Clover 

 and its Impurities," the more important impurities found in Eu- 

 ropean and American grown clover seed are given. Attention is 

 called to the introduction of bad seeds from Chile. In 1905 two 

 hundred and seventy-five thousand pounds of Chilean red clover 

 seeds were imported into the United States, and this clover seed 

 contained Chilean clover dodder seed. 



Canadian work. — In 1892 Prof. J. H. Panton called attention to 

 the importance of making an investigation of seed purity and of 

 carrying on a campaign for better and cleaner seed. He thought 

 a large number of the weeds on the Ontario farms were introduced 

 in clover seed. 



He found the number of weed seeds varied greatly, all the way 

 from one to four thousand five hundred and forty per half ounce. 

 Among the weed seeds he reported several that have become trouble- 

 some in the Mississippi valley ; these include ribgrass and chicory. 



Saunders in several reports of the Experiment Farms has dis- 

 cussed the vitality of grass and clover seeds. In 1903 there were 

 tested one hundred and eighty-six samples of clover. The highest 

 percentage of germination was low, the lowest 17 and the average 

 76.3. A large number of grass seeds were also tested. The work 

 has been continued by Saunders and Grisdale (1910) relative to 

 determining the climatic conditions favorable to high vitality of 

 seeds. 



Since 1903 the Department of Agriculture of the Dominion of 

 Canada has created a seed division with Mr. G. H. Clark in charge 

 of the work in purity and vitality tests. 



A very notable publication on the subject of weeds and weed 

 seeds has been contributed by Clark and Fletcher who have given 

 colored illustrations of the more important impurities found in 

 clover and other seeds. 



