19 



The docks are largely employed for purifying- the blood and as a 

 remedy in skin diseases. 



Imports and prices. — Runiex or dock roots are imported into this 

 country to the extent of about 125,000 pounds annually. The price 

 ranges from 2 to S cents per pound. 



COUCH GRASS. 

 Agropyron repens (L. ) Beauv. (Triticum repens L,.) 



Other common names. — Dog-grass, quick-grass, quack-grass, quitch- 

 grass, scutch-grass, twitch-grass, witch-grass, wheat-grass, Chand- 

 ler's grass, creeping wheat-grass, 

 devil's-grass, durfa-grass. Dur- 

 fee-grass, Dutch-grass, Fin"s 

 grass, quake-grass. (Fig. 9.) 



Range and habitat. — Couch 

 grass, like so many other perni- 

 cious weeds, was introduced into 

 this country from Europe, and is 

 now a most troublesome pest in 

 cultivated ground, causing the 

 farmer a loss of thousands of 

 dollars annually by taking pos- 

 - —ion of fields and clouding out 

 valuable crops. It is most abun- 

 dant from Maine to Maryland. 

 and westward to Minnesota and 

 Missouri, but is rather sparingly 

 distributed in the South. It is 

 gaining ground on farms on the 

 Pacini • -lope. 



Description. — This rather coarse 

 grass produce- several stems, 1 to 

 3 feet high, from a long, creep- 

 ing, jointed rootstock, and bears 

 densely flowered spike-like heads 

 resembling those of rye or beard- 

 It— wheat. The stems are round 

 smooth, thickened at the joints, 

 and hollow, bearing front five to seven leaves. These have a long 

 cleft -heath, and are rough on the upper surface. The heads or spikes 

 are terminal, solitary, compressed, with two rows of spikelets on a 

 wavy and flattened axis. 



Couch grass is one of the most difficult weeds to eradicate, on 



188 



i Fig. 9. — Couch grass ( Agropyron repens (L.) Beauv. 



