62 GRAMINEAE (GRASS FAMILY) 



eat greedily, and its matted " couch" of interlacing rootstocks make 

 it an unsurpassed soil-binder in steep gullies or on road embank- 

 ments where the ground must be guarded against "washouts." 

 But it is its very tenacity of life that makes it 

 such a pest when it gets into cultivated 

 ground. If it could be kept in its place, or 

 were not so hard to kill when it gets out of 

 bounds, it would be a welcome friend. 



The mischievous part of the plant is its 

 jointed, branching, underground stem, or root- 

 stock, which is capable of budding a new plant 

 at every joint and taking such entire posses- 

 sion of the soil that other plants growing with 

 it are so crowded and starved as to yield very 

 poor crops or none at all. The same joints 

 from which the buds shoot above ground also 

 send down clusters of fine, fibrous roots which 

 absorb most of the plant-food and moisture. 

 Culms one to three feet tall, with flat, ashy 

 green leaves, smooth beneath but rough above, 

 three inches to a foot long and about a third 

 of an" inch wide ; sheaths smooth, shorter than 

 the internodes. Fruiting spike erect, three to 

 eight inches long, with spikelets sessile and 

 alternately placed in each notch of the rachis 

 with the broad side turned toward it ; each 

 contains three to seven seeds, which are about 

 as long as a grain of wheat but not nearly so 

 plump. Indeed the whole spike looks some- 

 what like a slender head of wheat, and the 

 grass is a near relative of that noble grain. 

 FIQ. 31. Quack- The glumes of some seeds have a short awn, 

 or beard, and others have none; they do not 

 shell readily, and often the entire spikelet 

 breaks from the stalk. Too often the seed is an impurity of 

 wheat, rye, barley, clover, and other grasses, particularly brome- 

 grass and timothy. Also the plant is often infected with the 

 fungous disease known as "stem rust" of wheat. (Fig. 31.) 



