320 FIELD CROPS 



they are adapted, these plants will naturally improve from 

 year to year, as most of the fertility is returned to the soil 

 in the manure, and the clover increases the supply of nitrogen. 



399. Care of Lawns. Thorough preparation of the soil 

 and thick seeding are necessary to get immediate results in 

 lawns and to keep down weeds. No better lawn can be 

 made in our Northern states than one composed of blue grass 

 and white clover. Frequent clipping only serves to improve 

 it. If a good stand is obtained, there will be little trouble 

 from weeds; there will be no room for them. Lawns should 

 not be clipped too closely or too frequently in hot, dry 

 weather, for the roots are likely to "burn out" from exposure 

 to the sun. The land should be kept rich by the addition 

 of manure or commercial fertilizers, as the fertility is rapidly 

 removed in the clippings. 



400. Harvesting Blue Grass Seed. Most of the seed 

 of Kentucky blue grass is produced in a small area near 

 Lexington, Kentucky. The seed is stripped from the heads 

 by horse machines as soon as the panicles begin to turn yel- 

 low, which is about the second week in June. It is then 

 piled in windrows three or four feet deep to cure, and is 

 stirred thoroughly every day to keep it from heating. It is 

 cured in about ten days, when it is cleaned and prepared 

 for market. A good yield of seed as it is ordinarily cleaned 

 is from 125 to 200 pounds to the acre; when the seed is cleaned 

 to weigh 24 pounds or more to the bushel, the yield seldom 

 exceeds 75 or 100 pounds. 



401. Related Plants. Other species of Poa are of some 

 importance as pasture or meadow grasses in limited sections 

 of the country, particularly in New York and New England. 

 Canada blue grass, Poa compressa, is of some value as a 

 pasture grass in some sections of eastern Canada, New York, 

 and New England. It grows on poorer, heavier clay soils 



