BLUE-GRASSES 161 



the seeds were in the milk stage, and 2907 pounds when 

 the seeds were ripe. 



In Europe yields ranging from 3500 to 6250 pounds 

 an acre are reported, but most of these are based on very 

 small plots. 



Irrigated blue-grass at the Iowa Experiment Station 

 yielded 15,160 pounds green matter, and non-irrigated 

 10,360, the water contents of the grass being, respectively, 

 67 and 60 per cent. 



150. Seed-production. Commercial seed of Kentucky 

 blue-grass is gathered mainly in the blue-grass region of 

 Kentucky, especially the counties of Bourbon, Fayette 

 and Clark. In recent years increasing quantities are 

 harvested in northern Missouri and southern Iowa. 



The seed is harvested from about the 10th to the 15th 

 of June, as soon as the panicle has become yellow and 

 the grain firm. Where a large acreage is to be cut, how- 

 ever, the harvesting is begun sooner. Some of the seed 

 is gathered by means of hand strippers, but most of it 

 by stripping machines, of which various forms have been 

 devised. The most efficient machines are rotary strippers 

 in which a revolving cylinder studded with rows of nails 

 brushes the heads against a platform and into a receptacle 

 behind. 



The stripped heads must be carefully cured in order 

 to secure the best seed. This is commonly done in the 

 open, preferably where the ground has a hard smooth 

 surface. The seed is piled in long, narrow ricks, pref- 

 erably not over 18 inches high, which must be frequently 

 turned to accelerate curing and to prevent heating. 

 During the first few days each rick should be turned at 

 least three times a day. The viability of the seed is 

 greatly affected by the care used in curing, and lack of 



