increaser. A plant that increases at least temporarily as the result 
of overgrazing. 
inflorescence. The seedhead or flowering part of a plant. 
internode. That part of the grass stem between two nodes or 
joints. 
inundate. To cover with water as with a flood; overflow. 
invader. A plant that invades; enters and spreads to an area to 
which it is not native. 
involute. With the margins rolled inward. 
keel. The sharp fold at the back of a compressed sheath, blade, 
glume, or lemma. 
lance shaped. Several times longer than broad, broadest below the 
middle, and tapered toward the end. 
lemma. The bract of a spikelet above the pair of glumes. 
ligule. In grasses, a thin, membranous, hairy, or ridgelike appen- 
dage on the inside of the leaf where blade and sheath join. 
membrane. A thin, soft, pliable sheet or layer, serving as a cover- 
ing or lining. 
midrib. The central vein of a leaf. 
nerve. The vascular veins of lemmas, glumes, and blades. 
node. The joint of a grass stem. 
palatability. Indicated by the preference that an animal shows 
for a particular species, plant, or plant part. 
palea. The inner bract of a grass floret. 
panicle. A seedhead with a main axis and subdivided branches. It 
may be open or compact and spikelike. 
pedicel. The stalk of a spikelet. Opposed to sessile. 
perennial. A plant that produces aboveground parts from the 
same root system for at least three growing seasons. 
petiole. The stalk of a leaf blade. 
pistillate. Applied to flowers bearing pistils only and to a plant 
with pistillate (female) flowers. 
raceme. A seedhead in which the spikelets are pediceled on a 
rachis, as in the paspalums. 
rachilla. A small rachis ; applied especially to the axis of a spike- 
let. 
rachis. The axis of a spike or raceme. 
range condition. The present state of vegetation of a range site in 
relation to the climax or potential plant community for that 
site. 
rhizome. An underground stem with nodes, buds, and scalelike 
leaves. 
rib. Any of the main veins in a leaf. 
robust. Strong; healthy; hardy. 
rosette. A cluster of radiating basal leaves. 
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