440 COMPOSITAE (COMPOSITE FAMILY) 



sion to go where mosquitoes are troublesome ; it is also used in 

 medicine, and the dried plants are quoted at five to six cents a 

 pound in the drug market ; its juices are resinous and bitter, 

 and grazing animals will not touch the weed. The hands should 

 be protected when pulling or collecting the plants, for the oily 

 and acrid juices are sometimes very irritating to the skin, pro- 

 ducing an eruption which resembles that caused by the touch of 

 Poison Ivy. 



In good soil the stem may attain to a height of ten feet, and, 

 again, it will adapt itself to hard conditions and bloom when less 

 than six inches tall ; it is erect, finely 

 grooved, bristly with short hairs, simple or 

 branching from the base ; when cut it stools 

 freely, hastening to develop new fruiting 

 branches. Lower leaves spatulate or some- 

 times cut-lobed, tapering to petioles ; upper 

 ones usually entire, lance-shaped to linear, 

 finely hairy, much crowded on the stalks. 

 Heads in panicled clusters, very small and 

 very numerous, each about a sixth of an 

 inch broad, with smooth, cylindric invo- 

 lucre, nearly concealing the very small, 

 white rays. Seeds many and small, with 

 yellowish brown pappus. (Fig. 305.) 



Means of control 



Where not too abundant to make the task 

 impracticable, hand-pull the weeds and re- 

 move them from the ground, for the woody 

 stalks contain enough nutriment to mature 

 the first-opened flowers. Burn over stubbles 



FIG. 305. Canada on inf es ted grain fields for the purpose of 

 Fleabane (Engeron . , ^,, , 



canadensis). x }. destroying the seeds on the ground. Mead- 



ows badly "run to Horseweed" should be 

 put to a well-tilled hoed crop before reseeding. Plants of- roadside 

 and waste places should be pulled or cut in early bloom or before, 

 for the protection of adjacent property. 



