blue grass

CIDE DICTIONARY

blue grass,  

 A species of grass (Poa compressa) with bluish green stems, valuable in thin gravelly soils; wire grass.  [1913 Webster]

Kentucky blue grass, a species of grass (Poa pratensis) which has running rootstocks and spreads rapidly. It is valuable as a pasture grass, as it endures both winter and drought better than other kinds, and is very nutritious.