CULTURE OF GRASSES 



39 



estimate the proportion of good seed. A small magni- 

 fying glass is a help in this work as many of the grass 

 seeds are small (fig. i). If one wishes to know accurately 

 the proportion of good 

 seed it is necessary to 

 weigh the sample and 

 afterwards to weigh the 

 good seed. As farmers 

 usually do not possess 

 balances for weighing 

 such small amounts and 

 as these instruments are 

 expensive, it is best to 

 send samples to an ex- 

 periment station. How- 

 ever, a very fair estimate 

 can be made without 

 accurate weighing. 



The seed of grasses is enclosed in chaff which is not 

 usually removed in threshing. Timothy seed is fairly 

 free from chaff but seed of bluegrass and most other 

 grasses has a rather large proportion of chaff. The 

 value of seed depends, of course, on the amount of good 

 seed as distinguished from the chaff. The weed seeds 

 can be easily separated, and if there is more than a very 

 small amount, the grass seed should not be used for 

 sowing. In examining the seed of bluegrass, redtop, 

 etc., one should pick out the actual seed with a needle 

 or other small sharp instrument, so that he may know 

 just what he is looking for. A good seed is hard to the 

 touch like a grain of wheat (on a small scale) or a timothy 



I . Magnifying glass suitable for 

 testing the purity of seeds. 



