B. P. I.— 624. 



THE DISTINGUISHING CHARACTERS OF THE SEEDS 

 OF OUACK-GRASS AND OF CERTAIN WHEAT- 

 GRASSES." 



INTRODUCTION. 



In view of the noxious character of quack-grass, c{uitch-grass, or 

 couch-grass (Agropyron repens L.), the recognition of its seeds as an 

 impurity of commercial seeds is important and desirable. This 

 matter has special significance in connection with the seed of the 

 forage plant known as.awnless, or Hungarian, brome-grass (Bromus 

 inermis Leyss). Brome-grass is extensively handled in- the American 

 market, and much of the seed offered is imported either from Europe 

 or from the western provinces of Canada. 



Examination of samples of brome-grass seed taken from imported 

 lots shows that seed from Europe invariably contains seed of quack- 

 grass, which is rarely found in seed from Canada. In the place of 

 quack-grass seed the Canadian brome-grass seed usualh" contains seed 

 of one or another of the wheat-grasses which are native to the Western 

 States and to Canada and which have much the same habit of growth 

 as quack-grass. Since these wheat-grasses are native to this country 

 and to Canada, their seeds do not appear in brome-grass seed im- 

 ported from Europe. The seeds of the wheat-grasses are so similar to 

 those of c{uack-grass that they may readily be mistaken for the latter. 

 It becomes important, therefore, that the presence of the seed of 

 quack-grass in brome-grass seed be detected with certainty and that 

 lots of brome-grass seed carrving seed of wheat-grass onlv mav be 

 distinguished and not rejected as suspected of containing quack-grass 

 seed. 



The purpose of tliis- paper is to so point out the distinguishing char- 

 acters of the seeds of quack-grass and of the two kinds of wheat-grasses 

 chiefly involved that their presence as an impurity of brome-grass 

 or other forage-plant seeds may be practical!}' determined. 



« The distinguish iiffr of the seeds of quack-grass, one of the greatest weed pests in the 

 Northwest, from seeds of similar appearance is of importance in all regions where 

 quack-grass may become troublesome. In the present paper the characteristic 

 differences between the seeds of quack-grass and the seeds of other grasses of similar 

 appearance have been pointed out in such a practical way as to furnish a means of 

 readily determining the presence or absence of quack-grass seed in commercial seed. — 

 Wsi. A. Taylor, Acting Chief of Bureau. 



60309— Cir. 73—11 3 



