Testing Farm Seeds. 



381 



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-SaPUt. 



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TESTING KENTUCKY BLUEGRASS SEED. 



The Kentucky bluegrass seed in the American market is produced 

 in this country, chiefly in Kentucky. Seed in bulk has a brownish-straw 

 color. Individual seeds are canoe-shaped, approximately three thirty- 

 seconds of an inch long, the back of the lemma being sharply angled. A 

 slender ridge on each side of the angle of the lemma is usually evident 

 (fig. 9, a). 



The chief points to be considered in testing Kentucky bluegrass seed 

 are the presence of Canada bluegrass seed as an adulterant and the 

 presence of an undue amount of chaff or of dead seed. 



Canada bluegrass seed has been employed in large quantities as an 

 adulterant of or a substitute for Kentucky bluegrass seed. Its seed is very 

 similar to the latter, but can be distinguished by means of a magnifier. 

 In general Canada bluegrass seed in bulk has a somewhat lighter color. 



Its individual seeds (fig. 9, b) 

 .,v<?5s*v .-f^fSMk are broader, more blunt and pa- 



pery at the apex, and the sides 

 of the lemma are devoid of the 

 ridges wdiich are distinct in seeds 

 of Kentucky bluegrass seeds 

 (fig. 9, a and b; fig. 16). The 

 extent of adulteration is deter- 

 mined from 1,000 seeds of the 

 mixture counted indiscrimi- 

 nately. 



Since it is difficult to remove 

 all the sterile chaff from seeds 

 containing a grain, it will suffice in making practical tests to remove the 

 lightest chaff, pieces of stems, leaves, etc., as inert matter, endeavoring 

 to leave all the grain-bearing seeds with the pure seed, which by this 

 method will contain also some empty, or sterile, seeds. The pure seed and 

 chaff are separated by placing the weighed sample, a little at a time, on a 

 smooth cardboard tray and ]iouring it into another tray, allowing the 

 seeds to roll across the face of the tray. The light chaff is held behind, 

 while the heavier grain-bearing seeds roll off. Carefully repeating the 

 operation two or three times effects a very satisfactory^ separation. After 

 removing the foreign seeds, the seeds (200 in duplicate) for the germina- 

 tion test are to be counted out from the "pure seed'' separation, the 

 chaffy and grain-bearing seeds being taken indiscriminately. 



Fig. 



— Seede of timothy : a. Grains in 

 tlie huH, or chaff; b, grains removed 

 from tlie chaff; o, the same, natural 

 size. 



