48 MISC. PUBLICATION 3 6 9, U. S. DEPT. OF AGRICULTURE 



Reimer and Tartar (480), in 1919, obtained an increase in both the 

 sulfate-sulfur and organic-sulfur content of alfalfa grown in three 

 Oregon soils when they fertilized with 300 pounds of sulfur per acre. 

 Very large increases in the sulfur content of alfalfa were obtained by 

 Neller, using two Washington soils, the Ritzville and the Palouse silt 

 loams. The calcium content of the alfalfa was lowered and the phos- 

 phorus content was increased, but no significant change was observed 

 in the potassium or nitrogen contents. Ligon (353) , on the other hand, 

 reported in 1935 that 1,000 pounds of sulfur applied per acre of muck 

 soil in Michigan resulted in a decrease in the phosphorus as well as the 

 calcium in the plant, with little or no change in potassium or nitrogen. 

 Increases in the sulfur content of alfalfa following fertilization with 

 sulfur, gypsum, or ammonium sulfate were found by Evans and 

 Greaves (169). m 



No increase in the sulfur content of the plant was found by Barbier 

 (46), who investigated the influence of sulfur and chlorine on the 

 mineral nutrition of the plant. In the case of beets, an increment in 

 the chloride content brought about by fertilization with chlorides was 

 accompanied by an increment in the basic ions. 



The addition of aluminum to culture solutions containing phos- 

 phates did not result in an appreciable increase in the aluminum con- 

 tent of lettuce, but the aluminum content of the roots was more than 

 doubled, according to some investigations of Pierre and Stuart (465), 

 reported in 1933. They state: 



The results obtained definitely show that the problems of aluminum toxicity and 

 phosphate availability are very closely interrelated. The so-called toxic action 

 of soluble aluminum in very acid soils can be ascribed to two general causes. 

 First, aluminum in high concentration directly injures the root hairs and thus 

 causes stunted and poor development of the roots. Secondly, the aluminum 

 absorbed by the plant precipitates part of the phosphate present, which interferes 

 with phosphate translocation and assimilation. The addition of large amounts 

 of phosphorus to the soil precipitates some of the aluminum out of the soil solution 

 and enables the root to obtain a sufficient amount of phosphorus for nutritional 

 purposes. 



Hester (266) found that aluminum appeared in the soil solution at 

 pH 3.9 to 4.4 in Portsmouth loamy fine sand, 4.2 in Bladen sandy 

 loam, and 5.2 and below in Norfolk fine sand. He claimed that this 

 was directly responsible for the low yields at these pH values, a 

 problem that was overcome by applying lime to the soils. Other 

 studies of aluminum in plants include those of Mvers and Voegtlin 

 (424) in 1914, Burgess and Pember (97) in 1923, Winter and Bird 

 (597) in 1929, and Meunier (407) in 1935. 



Densch and Hunnius (149) reported, in 1924, that fertilization with 

 copper sulfate, although increasing yields of barley grain, caused no 

 change in the mineral content of the plant except to depress the amount 

 of iron assimilated. 



Elvehjem and Hart (166) reported in 1929 increases of from 10 to 

 148 percent in the copper content of different vegetables when 50 

 pounds of copper sulfate per acre was used. Miller and Mitchell (411 ) 

 in 1931 were able to increase the copper content of lettuce fourfold by 

 adding 20 pounds of copper sulfate per acre in four equal doses. Much 

 smaller increases were obtained in spinach. Copper had a slight 

 depressive action on manganese and a stimulative action on the 

 assimilation of iron, under the conditions of their experiments. Arnd 

 and Hoffman (15) and Coleman and Kuprecht (119) reported that 



