218 LEGUMINOSAE (PULSE FAMILY) 



marks are often bordered by thickets of Black Cherry sprouts. 

 The leaves of this and kindred plants, under certain conditions, 

 contain a dangerous quantity of hydrocyanic acid, commonly called 

 prussic acid, a most virulent poison. When eaten by cattle and 

 sheep, the complex chemical changes that take place within the 

 animals' stomachs liberate the poison, frequently with fatal effect. 

 The common Choke Cherry (Primus virginiana) also con- 

 tains prussic acid, but in a less amount than the Black Cherry. 

 Leaves from large trees or old but stunted shrubs are not nearly so 

 dangerous as leaves from young, rapidly growing sprouts. Both 

 fresh and wilted leaves are poisonous, but chemists have demon- 

 strated by experiment that "Leaves wilted in bright sunlight to 

 about 75 per cent of their original weight, or until they begin to 

 appear slightly limp and to lose their gloss, yield the maximum 

 amount of prussic acid." It is stated that a half-pound of Black 

 Cherry leaves is a fatal quantity for a cow to eat, and a much less 

 quantity will kill a sheep. 



Means of control 



Yearling Cherry sprouts may be easily and quickly pulled when 

 the ground is soft, leaving no stubs to put forth more leaves. Older, 

 shrubby growths should be closely cut, or, better, grubbed out, 

 before coming into leaf, if they are situated where cattle or sheep 

 are likely to browse them. Often grazing animals will eat litter 

 that is lying on the ground, even though they have not contracted 

 the habit of browsing from standing growth ; therefore all the 

 brush cut should be put out of harm's way by piling and burning. 



WILD SENNA 

 Cdssia marildndica, L. 



Other English names: American Senna, Yellow Locust Plant. 



Native. Perennial. Propagates by seeds. 



Time of bloom: July to August. 



Seed-time: September to October. 



Range: New England to Florida, westward to Michigan and 



Indiana. 

 Habitat : Moist, open ground ; pastures and meadows. 



The roots of Wild Senna are spreading, contorted, woody, and 

 black, mostly horizontal, but yet gathering nourishment from the 



