GRASSES. 9 
internodes, when the overground stems appear scattered and the 
whole plant forms a more or less spreading mat, as in Red Fescue. 
In other cases the internodes are very short. The overground stems 
are then close together and the plant develops into one of the 
bunch grass type, such as Sheep’s Fescue. Although characteristic 
of a certain species, the type may be modified by the soil. Thus, 
stiff, compact soil is apt to prevent the development of creeping 
rootstocks, and the plant may assume a more or less bunchy appear- 
ance. On the other hand, bunchy plants often develop looser tufts 
in open, loose soil than in stiff clay. 
Stems: The stems of the grasses, generally called culms, are 
hollow, except in corn, in which they are solid, but are closed at 
intervals by variously coloured swollen parts called nodes or joints. 
The parts of the stems between the nodes are called internodes. 
Immediately above the nodes a small portion of the stem remains 
soft and continues to grow during almost the whole life of the plant, 
but the upper part of the internode soon becomes firm and stops 
growth. This enables the stems, if they are not too old, to regain 
their upright position when lodged by wind or rain. 
Leaves: The leaves consist of two distinct parts. The lower 
encloses the stem like a tight case, usually open along one side. It 
is called the sheath. The upper part, the blade, is 
generally long and narrow. Where the plants have 
sufficient moisture the blades are flat; during drought 
they are often rolled together and bristle-like, turning 
their upper surface outward. A plant which during 
excessive drought has bristle-like leaves may display 
flat ones if moisture becomes abundant in either air or 
soil. As the moisture secured by the root evaporates 
chiefly through the lower surface of the leaf, the 
rolling together of the blade during drought prevents 
loss of moisture and thus saves the plant from perishing 
Fig. 2-Sheath and of thirst. Where the blade is attached to the sheath 
lower part of leaf 
of Timothy. there is generally a thin membranous appendage, of 
pee varying size and shape, called the ligule. (Fig. 2, L.). 
Inflorescence: The flowers are in inflorescences which, however 
different they may look, are always constructed on the same prin- 
ciple. That of Kentucky Blue Grass is typical (Plate 10). It 
consists of branches arranged in whoils at the upper joints of the main 
stem. When the branches are elongated, as in the Blue Grasses, 
