8 Nebraska Agricultural Exp. Station, Research Bui. 13 
15. Regarding three plants per hill as a perfect stand, 
the reduction in yield of corn was not proportional to a reduc- 
tion in stand. With single-row plats, stands averaging 92.8, 
87.2, 82.7, 77.8, 73.1, 66.6, and 43.0 per cent yielded respec- 
tively 85.5, 88.1, 83.5, 82.2, 77.9, 74.8, and 56.7 bushels per 
acre. 
16. Satisfactory yield correction for corn based upon 
per cent of stand cannot be made, because the effect upon 
yield depends upon the distribution of the missing plants 
and because the effect upon yield is not proportional to the 
per cent stand. Comparable yield tests of similar varieties 
or strains of corn may be secured by basing the yield upon 
a counted number of hills containing a uniform number of 
plants and surrounded by a full stand. 
17. Corn varieties or types differing markedly in growtli 
characteristics should be tested at several rates of planting, 
because the optimum rate for one is not necessarily that for 
another. Thus, as an average for two years. Pride of the 
North and Calico produced their maximum yield when grown 
at the rate of five plants per hill, while Mammonth White 
Pearl yielded best at the three-rate. In 1914, Pride of the 
North yielded most at the five-rate, University No. 3 did 
equally well at the two and three-rate, while Hogue's Yellow 
Dent produced best at the two-rate. 
18. The removal of suckers affects the yield of varieties 
differently, and for this reason suckers should for no reason 
be removed in comparative variety tests. 
19. In comparative jaeld tests where it is not conven- 
ient to harvest and thresh the entire plats, fairly reliable 
results may be obtained by harvesting and averaging a large 
number of systematically distributed small fractional areas 
or quadrates from each plat. The necessary number of 
quadrates to be representative will vary with the size of the 
plats. 
Twenty 32-inch quadrates harvested from thirtieth-acre 
wheat plats gave fairly reliable results. Less than 20 proved 
likely to be unrepresentative of the plats. Very satisfactory 
results were obtained by having 40 quadrates represent one- 
fifteenth acre of wheat. 
20. Two hundred and seven thirtieth-acre plats were 
grown to a uniform crop of Kherson oats for the purpose 
of studying various phases of experimental error. Calcula- 
tions have been made from them to show: (1) The use and 
