ANNUAL REPORT, 1936 11 



The Absorption by Food Plants of Chemical Elements Important in 

 Human Nutrition. (Walter S. Eisenmenger and Edward B. Holland.) 

 Salts of iron, copper, manganese, and iodine were applied to plots growing 

 spinach, lettuce, onions, beets, and carrots. Ferric oxide applied did not 

 increase the amount of iron in the plants. The hydrogen-ion concentration 

 of the soil is probably more of a factor in iron assimilation than is the amount 

 of insoluble iron compound present. Applied copper increased the amount 

 of copper in most plants over that found in the checks. Manganese gave incon- 

 sistent results as to amounts in plants in the manganese plots and in other plots. 

 Iodine in the plants was not determined. 



There was ample evidence that applications of manganese tend to increase 

 the amount of phosphorus in the plants. 



Time of Cutting Alfalfa. (Walter S. Eisenmenger and Karol J. Kucinski.) 

 An alfalfa field of rather even stand was cut at different times to determine the 

 best returns in yields. Eight plots were cut three times and four plots were 

 cut twice. The higher yields were associated with those cut three times. The 

 highest yield was obtained when the first cuttings were made on June 13, the 

 next on August 1, and the last on September 1. 



Proportion of Mixtures used in Seeding for Hay. (Walter S. Eisen- 

 menger, Ralph W. Donaldson, and Karol J. Kucinski.) Alfalfa, red clover, 

 timothy, orchard grass, and red top were seeded in different proportions. The 

 three totals in pounds per acre of seed applied were 21, 17, and 13, and thirteen 

 different combinations at each of these rates were seeded. Thus there were 

 thirty-nine (39) variations. This year the seeding at the rate of 17 pounds 

 per acre yielded 17,130 pounds of hay. This was the maximum for two cuttings. 

 The hay contained 61 percent of red top and 39 percent of alfalfa. One of the 

 lowest in yield was the plot where 13 pounds of seed were used and the hay 

 contained 100 percent alfalfa. The yield for two cuttings was 10,539 pounds. 



Alfalfa Variety Tests. (Walter S. Eisenmenger and Karol J. Kucinski.) 

 In cooperation with the United States Department of Agriculture, tests are 

 being conducted with fifteen varieties of alfalfa. Two varieties for this year, 

 Ladak and Hardigan, seem to have promise for yields, while such varieties 

 as Utah and Oklahoma Common do not as yet yield adequately. 



Potato Variety Tests. (Ralph W. Donaldson, Walter S. Eisenmenger, 

 Arthur I. Bourne, and Karol J. Kucinski.) The variety test for comparison of 

 yields was continued this year on the experiment station farm. Each plot 

 received eleven applications of Bordeaux mixture, 5-5-5. The yields com- 

 pared on the basis of bushels per acre are as follows: 



1936 1935 



Green Mountain 449.4 444 



Russet Rural 429.5 384 



Golden 397.9 280 



Chippewa 384.0 542 



Katahdin 329.1 423 



Irish Cobbler 319.8 



The Comparative Nutritive Effects of Copper, Zinc, Chromium, and 

 Molybdenum. (H. Robert DeRose, Walter S. Eisenmenger, and Walter S. 

 Ritchie.) In carefully purified white sand washed with aqua regia and later 

 washed with water and then heated at 100° C, tomatoes, buckwheat, and barley 

 were planted in crocks with capacity to drain at the bottom. Knop's solution 



