FIELD CROPS. 29 



Another point of special interest observed in these experiments was 

 that applications of phosphoric acid were beneficial to clover on soil 

 which was not actually poor ia phosphoric acid and on which cereals do 

 not generally respond to applications of this element of plant food. 



Field experiments with corn, 1893, G. E. Morkow and F. D. 

 Gardner {Illinois Sta. Bui. 31, pp. 333-360). 



Synopsis. — Accouuts are given of experiments in the following lines: (1) Test of 

 varieties, (2) time of planting, (3) depth of planting, (4) thickness of jilanting, 

 (5) planting in hills and drills, (6) frequency and depth of cultivation, (7) root- 

 liruniug, (8) continuous cropping rs. a rotation of crops, (9) time of harvesting, 

 and (10) cross fertilization. The results of these and previous experiments at 

 the station favor (1) medium maturing varieties with ears above the average in 

 size, (2) planting from May 10 to 15, (3) shallow planting, (4) planting from 

 about 12,000 to 24,000 kernels per acre, (5) either hills or drills, (6) only enough 

 cultivation to keep the soil free from weeds and surface well stirred, (7) the 

 avoidance of root-pruning, (8) rotation of crops, (9) late harvesting, and (10) 

 cross breeding to increase yield. 



The experiments in 1893 were in continuation of those reported in 

 Bulletin 25 of the station (E. S. R., 4, p. 409). As in previous years, 

 the experiments were conducted on dark-colored, fertile prairie soil 

 about 18 in. dee]), with a yellow clay subsoil. As a rule, there were 

 4 plants in hills 3| feet apart each way. For the 3 months beginning 

 June 11 the rainfall was only 0,94 in. The temijerature during all the 

 growing season was somewhat below the average. 



Varieties (pp. 337-351). — The test of varieties occupied 119 plats." 

 The results are given as heretofore in detail in tables, summaries, and 

 general notes. Mixtures of 2 and 4 varieties in 4 out of 5 cases gave 

 larger yields than the single varieties, a result directly opposed to that 

 secured in 1892. " No variety has been shown to be greatly superior 

 to the others, nor has it been shown that the yield depends upon either 

 the color of the kernel or on the exact shape of either the ear or 

 kernel." 



Time of planting (pp. 351-353). — Burr White was planted at intervals 

 of a week from May to June 17. The largest yield was from plant- 

 ing May 13, closely followed by the planting of May 6. " Taking the 

 average of 6 years, the largest yield was from planting May 11 to 16, 

 with but little decrease in yield from planting anytime from April 27 

 to May 23." 



Depth of planting (p. 353). — The results of planting corn at depths of 

 from 1 to 7 in. during 5 years are tabulated. The yields decreased as 

 the depth of planting increased. 



Thickness of planting {i^p. 353-355). — Tabulated data are given for 

 experiments, iu which from 1 to 4 kernels were planted in hills from 3 to 

 coin, apart. "The result of all trials at the station clearly indicates 

 that in average seasons, in central Illinois at least, a lessened yield 

 may be expected if the number of stalks is less than 3 in a hill." 



