B. P. I.— 176. 



THE SEEDS OF THE BLUEGRASSES. 



I. THE GERMINATION, GROWING, HANDLING, AND 

 ADULTERATION OF BLUEGRASS SEEDS. 



By Edgar Brown, 

 Botanist in Charge of Seed Laboratory. 



DESCRIPTION OF COMMERCIAL AND HAND-GATHERED SEEDS. 



Great difficulty is experienced in distinguishing- the seeds of the 

 species of Poa. It is especially important to be able to recognize 

 them, as the species vary greatly in value and the seed of one species 

 is frequently substituted for that of another. 



The descriptions of the seeds of Poa already published have been 

 largely those of complete or hand-gathered specimens. But the seeds 

 of some kinds as they appear on the market are more or less broken 

 and have lost man}^ of their distinguishing characters. The process 

 of cleaning often rubs oil' the web at the base of the seed and the 

 hairs along the sides and breaks the tip. On this account descriptions 

 based on specimens of perfect seeds are not to be relied upon in 

 identifying certain commercial Poas. 



The mutilation of seeds during the process of cleaning is especially 

 marked in home-grown seed of Kentucky bluegrass {Poa pratensis). 

 Even the hand-gathered seed of rough-stalked meadow grass {Poa 

 trivialis) is frequently so much injured about the slender apex as to 

 increase greatly the difficulty of distinguishing it from that of Ken- 

 tucky bluegrass. On the other hand, the commercial seeds of wood 

 meadow grass {Poa netnoralis) and fowl meadow grass {Poa trifloi'd) 

 retain much of the pubescence on the glume, often the web, and are 

 usually not broken on the tip. 



It is important that descriptions and illustrations to be used in prac- 

 tical seed testing be taken from the commercial as well as hand- 

 gathered seed and be comparative in character. Those given in this 

 paper have been prepared from ])oth hand-gathered and commercial 

 seed. The term seed is here used in its popular sense. 



5813— No. 84—05 2 9 



