62 A TEXT-BOOK OF GRASSES 
soft and the dark green color is agreeable to the eye. It 
can be grown successfully without irrigation in the north- 
eastern states as far south as Virginia and Tennessee, and 
farther in the mountains, and west to Minnesota and 
eastern Kansas, also in the humid region of Oregon and 
Washington, and in the western mountains. Throughout 
most of the northern half of the United States beyond the 
limits mentioned it can be grown with the aid of irrigation. 
Even in the humid region it may be necessary to supply 
water during the dry periods in the summer. 
In the southern half of the United States, except in 
the mountains, blue-grass does not thrive even when 
irrigated, although, except in the lower coastal plain, it 
may with special care make a fair growth. In the humid 
region it may fail because of the character of the soil. 
Thriving best on limestone soils, it fails to giye good 
results on acid soils. Hence, blue-grass is not adapted to 
much of the coastal region from New England to Virginia. 
Often it is practicable to correct the soil acidity by the 
addition of lime. 
79. Rhode Island bent is especially adapted to that 
portion of the humid region in which blue-grass fails 
because of soil acidity, as it thrives under moist, moder- 
ately acid conditions. Rhode Island bent does not pro- 
duce vigorous creeping rootstocks as does blue-grass, but 
nevertheless will form a fairly firm and uniform sod. 
For a description of Rhode Island bent and its relation 
to redtop, see Par. 234. Creeping bent is another form of 
redtop, with creeping or stoloniferous stems, which pro- 
duces a lawn of good color and texture. 
80. Bermuda-grass answers all the requirements of 
an ideal lawn grass except that of color. To many people 
the light gray-green color is not so pleasing to the eye as 
