100 GRASSES AND HOW TO GROW THEM. 



tained for pasturing for prolonged periods crowds out 

 nearly all kinds of weeds. Among the exceptions are 

 ironweed (Venionia noveboracensis), blueweed {Ec'hi- 

 um vulgare), the oxeye daisy (Chrysanthemum leucan- 

 themum) and in some instances the Canada thistle 

 (Cirsium arveiise). When these are present in any 

 considerable mimbers it may be advantageous to clip 

 them annually with the scythe or with the field mower 

 to prevent them from maturing seed, as live stock are not 

 likely to graze them off. 



Harvesting for Hay. — Blue grass being rather a pas- 

 ture than a hay j^lant, is not usually made into hay, 

 unless in the absence of better hay products. It is not 

 sufficiently bulky, hence the yield per acre is not large, 

 and Tinless c\it with much promptness as soon as it 

 reaches the proper stage, it becomes woody. To secure 

 a large amount of blue grass hay would necessitate 

 mowing over a relati\(3ly large area in proportion to 

 the bulk. But this does not mean that blue grass does 

 not produce a large amount relatively of pasture per 

 acre, since, in growing pasture, it virtually produces 

 two growths in the year, that is, in the spring and in 

 the autumn. i^Tor do the above remarks apply equally 

 to the variety Poa coDipressa, which, in suitable soils, 

 will yield at least a ton per acre of good hay. The crop 

 is not bulky, but it weighs very heavily in proportion to 

 its biilk and the hay is much relished, especially by 

 horses. Moreover it has the peculiar property of gum- 

 ming the knives of the mower while it is being cut. 



Blue gi'ass is ready for being cut when in early bloom. 

 It is not difficult to cure, hence, in good weather it may 



