114 MANUAL OF POISONOUS PLANTS 



mentioned. Dr. Rusby refers to its irritating properties when taken in excess 

 especially because of its action upon the urinary organs. One case referred 

 to by Dr. Johnson was extreme and serious. 



Sisymbrium officinale Scop. Hedge Mustard. 



This plant is widely distributed in this state, as a weed, and produces more 

 trouble than mustard. 



Sisymbrium altissimum L. Tumbling Mustard. 



This weed is common in grain fields in the north and may thus find its way 

 into wheat screenings which should be fed with caution. It probably produces 

 sinapism, as do the other plants of the order. It is also found in Iowa. 



Brassica arvensis (L.) Ktze. Charlock. 



This weed produces sinapism. After the application of the powdered ma- 

 terial, there is a sense of burning. The volatile oil of mustard is a powerful 

 irritant, and caustic, and should be used with caution. 



Thlaspi arvense (Tourn.) L. Penny Cress. 



This weed is said to be injurious to animals in Canada and is more or 

 less avoided by them in pasture. It is widely distributed in Northern United 

 States, but is more abundant in Canada. 



Capparidaceae. Caper Family. 



Cleome serrulata Pursh. Stinking Clover. 



This plant is more or less pungent and acrid; it is widely distributed from 

 Missouri River westward across the continent, especially along railways, etc. 

 The flowers are showy and purple. 



Cleome lutea Hook. Western Cleome. 



This plant is a western species with yellow flowers and has similar prop- 

 erties to the one named above. 



Polanisia graveolens Raf. 



Fetid annual, with glandular hairs and common in sandy soils in the eastern 

 States. The P. trachysperma T. & G. is similar to the preceding. This 

 plant is found from Iowa to Kansas. 



Sarracemaceae. 



Sarracenia purpurea L. Side-Saddle Flower. 



Probably not native to Iowa, although it is found distributed with Drosera 

 in sphagnum bogs. It contains the substance sarracenin. The root produces 

 diuresis, gastric excitation, and an increased, irregular action of the heart. 

 It produces papular eruptions changing to vesicular with depression as in 

 smallpox. The plant was formerly used medicinally by the Indians. 

 Droseraceae. Sundew Family. 



Drosera rotundifolia L. Sundew. 



Sundew is said to be poisonous to cattle. In bogs in the northern states. 



Greshoff reported hydrocyanic acid in this species and in D. intermedia. 

 Several other species in Europe were reported as harmful and toxic to cattle. 

 Crassulaceae. Orpine Family. 



Sedum acre L. Stone Crop. 



Produces inflammation when applied to the skin of many persons. The 

 juice is acrid and biting. 



Other species of this genus are known to be acrid. Several species with 

 yellow flowers are common in rocky soils in the Rocky Mountains. 



