Arizona Agricultural Experiment Station 561 



The average monthly composition for the four years ended 

 January 1, 1921, was as follows : 



1917 1918 1919 1920 



Total solids 308 266 262 256 



Chlorides 209 182 173 158 



During the year 1920, the sample for April is missing. It 

 would appear that a marked and steady improvement in the 

 drainage from this very alkaline area is taking place. Further 

 discussion of this project will be found in the Twenty-Seventh, 

 Twenty-Eighth, Twenty-Ninth, Thirtieth, and Thirty-First 

 Annual Reports of this Station. 



PRUSSIC ACID POISONING BY JOHNSON GRASS 

 In June, 1921, Mr. WiUiam H. Griffin of Cornville, Arizona, 

 reported to His Excellency, Thomas E. Campbell, Governor of 

 Arizona, the sudden death of three head of cattle and sent sam- 

 ples of the Johnson grass they had been eating. The letter and 

 samples were referred to this department. We had been called 

 upon previously to examine Johnson grass that was believed to 

 have caused the death of hogs; but the analyses were always 

 negative, although there was little doubt but that the hogs died 

 of prussic acid poisoning, and it had been shown in Bulletin No. 

 90, Part IV, 1905, of the Bureau of Plant Industry, that Johnson 

 grass did sometimes cause such poisoning. The samples in this 

 case contained surprisingly large amounts of prussic acid, but 

 no quantitative determination was made. The following descrip- 

 tion of the death of the animals is taken from Mr. Griffin's 

 letter : 



"I have lost three head of cattle the last two months by eating this 

 grass. The first was a two-year-old steer that broke through the fence, 

 stayed in the pasture about one hour, then came back to the fence and 

 died in a few minutes. The next was a milk cow that came fresh in 

 the morning and stayed about the corral all day. We gave her a good handful 

 of the Johnson grass and she died in less than an hour. The last was a 

 milk cow that broke into the horse barn and got a small amount which 

 was left by the horses. I milked this cow at eight o'clock and she was 

 in good health. At a quarter to nine we heard her calling and before 

 nine she was dead, in less than an hour after eating the grass." 



Since other cases of this kind are likely to occur, it is well 

 to call attention to the best known treatment of sorghum poison- 

 ing in cases where the animals are not beyond help. Glucose, 

 best known in the form of Karo corn syrup, greatly lessens 

 the toxic effect of prussic acid. It should be administered 

 freely. Milk sugar is also an antidote, and whole or skimmed 

 milk should be given freely. Animals that have just received 



