IMPORTANT POISONOUS PLANTS 



139 



and we may well in the absence of evidence suspicion this one." The aster is 

 confined to Gumbo clay soil intermixed with gravel and soil that contains more 

 or less alkali and other salts. 



Dr. O. L. Prien is investigating the disease. 



Fig. 19m. Fetid Marigold (Dysodia chrysanthiemoides). Pungent odor said to be injuri- 

 ous. (Charlotte M. King). Fig. 19n. Dog Fennel (Anthemis cotula). Contains a pungent 

 principle. 



Rudbeckia lacinata L. Cone-flower. 



In moist grounds throughout the north. Dr. Schaffner says it is supposed 

 to be poisonous to sheep. 



Bidens frondosa L. Black Beggar-ticks. 



Common in the north. The downwardly barbed awns are irritating. 



Coreopsis discoidea T. & G. Small Beggar-ticks. 



Very common in the east. It is a local irritant. 



Helenium autumnale L. Sneezeweed. 



It is common in low grounds throughout Iowa and is used by the Indians 

 to produce sneezing. The whole plant and flowers are poisonous to cattle and 

 sheep. 



Helenium tenuifolium Nutt. Sneezeweed. 



