562 Thirty-second Annual Report 



a good grain ration are much less susceptible to sorghum or 

 Johnson grass poisoning. Hay that is cured quickly is more 

 apt to retain dangerous amounts of prussic acid than hay that 

 is cured slowly. It is generally believed that the sorghums are 

 likely to be poisonous when the growth is stunted by drought. 

 Crawford in Bulletin 90, cited above, quotes a California cor- 

 respondent: "This plant is poisonous when grown on irrigated 

 as well as on non-irrigated lands, but especially so when grown 

 on irrigated lands, and the growth has become rank. It has 

 been shown that sorghums grown in Florida under humid con- 

 ditions also contain hydrocyanic or prussic acid. Great care 

 should be exercised in feeding Johnson grass or other sorghums, 

 especially after the sudden or mysterious death of any animal 

 that has had access to these forages." 



MISCELLANEOUS 



A large number of samples of irrigating water and of soil 

 for alkali have been analyzed during the year. The Chemist 

 made one visit to the Casa Grande Valley and in company with 

 County Agent Turville examined several alkaline districts. One 

 case in particular was of interest. The soil, which was wet and 

 sticky, even after a long dry period, was found to be heavily 

 impregnated with calcium and magnesium chlorides. The native 

 vegetation over this area was mostly saltbush. 



Twenty-four samples of water from the Agua Fria River, 

 representing the daily flow from January 5 to February 13, 

 1920, with a few omissions, were analyzed. The samples were 

 all of excellent quality, although they carried a small amount 

 of black alkali. 



A number of samples of feeds, guanos, manures, rocks, 

 insecticides, linseed oils, medicinal herbs, and other materials 

 were examined and reported on, although in only a few cases 

 were quantitative determinations made with this class of mate- 

 rials. One sample of so-called boiled oil which killed two valu- 

 able horses proved to be commercial rosin oil. 



