B. P. I.— 194. 



IV.-THE POISONOUS ACTION OF JOHNSON GRASS." 



By A. C. Crawford, Phminacologisf, Poisonous- PI ant Investigations. 



Johnson grass, which was introduced from Turkey into this countr^y 

 about 1830,^ has spread so that in many places it is considered as a 

 weed and pest/ Some farmers, however, have utilized the dried 

 grass as ha}' with advantage, either alone or combined with other 

 food material,'^ and chemical analyses have proved its value as feed. 

 Recently reports have come to this office from California of the death 

 of cattle under such circumstances as to point to Johnson grass as the 

 causative agent — the cattle dving in thirty minutes after eating the 

 grass. Johnson grass belongs to the same genus of the Gramineae as 

 sorghum. This group has been partially investigated chemically, and 

 it has been found that the fresh green plants of various members yield 



"This office has from time to time received communications from stockmen, 

 especially in the lower part of California, Arizona, and adjacent territory, expressing 

 a suspicion that the eating of Johnson grass had caused the death of stock with 

 rather sudden and violent symptoms. There has seemed to be little ground in 

 poisonous-plant literature to support such an explanation. Last summer, however, 

 convincing observations were reported from California by a stockman who had lost 

 heavily, and a supply of the grass in question was obtained. The result of the study 

 of this material was so positive, and the possibility of damage due to this unsuspected 

 forage plant so clear, that this preliminary notice is put out in the hope of getting 

 observations and material for study from many sources, in order, if possible, to 

 determine the conditions under which the poisonous properties are developed and 

 over how wide an area they are likely to appear. 



Rodney H. True, Physiologist. 



Office of PoisoNors-PL.\NT Investigations, 



]V(is}tliu/tnn, D. C ., Decemfter II, WO.'i. 



^Ball, C. R. Johnson Grass. Bui; No. 1], Bureau of Plant Industry, United 

 States Department of Agriculture, 1902. 



<^Spillman, W. J. Extermination of Johnson Grass. Bui. No. 72, Part 111, 

 Bureau of Plant Industry, United States Department of Agriculture, 1905. 



f'North Carolina Agricultural Experiment Station, Bui. 97, p. 92; Vasey, G., 

 Grasses of the South, Bui. No. 3, Division of Botany, United States Department of 

 Agriculture, 1887; Report of the Commissioner of Agriculture for 1881, pp. 281, 232, 

 239, 241; Report of the Secretary of Agriculture, 1890, p. 381. 



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