ANNUAL REPORT, 1944-45 9 



limited degree of chlorosis when magnesium is not sufficient for normal growth. 

 The development from apocarpy to syncarpy marks an apparent diminution in 

 need for the magnesium ion. 



Long-Time Field Fertility Tests. (Walter S. Eisenmenger and Karol J. Ku- 

 cinski.) Fifty-five to sixty years ago a series of soil test plots was established to 

 study the effects on the soil and crops of a long-time fertilizer program. Various 

 types of crops have been grown on these plots with the original plan of fertiliza- 

 tion being followed each year. For the last three years the crop has been hay. 

 Plots which receive a complete fertilizer and lime are outstandingly superior to 

 all other plots. Check plots which have not received any kind of fertilizer since 

 the inauguration of the tests show complete crop failure^ with "haircap" moss 

 coming in during the second season after seeding. In preliminary tests, rabbits 

 fed grass grown on the limed plots showed growth curves superior to those of 

 rabbits fed grass grown on the unlimed plots. 



&< 



Young Sunflower Plants 

 The large leaves shade the ground preventing the growth of weeds. 



Sunflowers and their Possibilities. (Karol J. Kucinski and Walter S. Eisen- 

 menger.) Results of tests for several years show that sunflowers will grow- 

 abundantly in this region, producing good yields on any land which will grow 

 corn. Sunflowers are hardy to light frost, and can be planted when it is safe to 

 plant field corn. The plants are much more resistant to frost when they first 

 come up than at the four or six leaf stage. Field trials have shown that the 

 best spacing is one seed every 18 inches in 36-inch rows for the tall varieties like 

 the Mammoth Russian. For shorter varieties like the Mennonite or Sunrise, 

 12 inches between plants and 36 inches between rows is recommended. Last 

 year's trials indicate that the shorter-growing Canadian varieties (Sunrise and 

 Mennonite), although yielding about 500 pounds less seed per acre, were superior 

 to tall-growing varieties like Mammoth Russian in ability to withstand wind 

 storms. The labor involved in taking care of sunflowers during the growing 

 season is very little, since the plant starts to grow rapidl}' and soon shades the 

 ground completely, killing any weeds that may survive the one or two early 



