Proc. American Breeders Association (1906)
THE CORN PLANT AS AFFECTED BY RATE OF PLANTING

E. G. Montgomery
Univ. Nebr., Lincoln, Nebr.

Barren stalks.—The number and percentage of barren stalks is directly affected by rate of planting. In 1904 the percentage of barren stalks varied from 6 per cent in the thinner planting to 27 per cent in the thickest planting.


Bul. Agr. Exp. Sta. Nebraska, 22(2): 28-31 (Dec. 15, 1909)
THICK AND THIN PLANTING FOR GROWING SEED CORN
E. G. Montgomery

It is a general custom among seedsmen to plant their corn intended for seed rather thin, in order to develop large ears. This, however, does away to some extent with natural selection. For example, we find when planting corn at the rate of 1 plant per hill, 3 feet 8 inches apart, that about 25 good ears weighing 12 ounces or more are produced to every 100 plants. When 3 plants per hill are planted, only about 10 good ears are produced on 100 plants, and when we have 5 plants per hill, only about five 12-ounce ears are produced to 100 plants. It seems that a plant which, when planted as thickly as 5 plants per hill, is capable of producing a good ear must be unusually vigorous. When planted thin, however, it is not possible to tell which of the good ears produced would have been good if the stalks had been planted thick. Again, in thin planting we have only a small number of barren plants, usually less than 2 per cent, but the thick planting averages about 11 per cent barren plants. In other words, in thick planting, natural selection determines which plants have the natural vigor to produce when conditions are somewhat adverse. To secure data regarding this, an experiment was started in 1905. Corn was grown at three rates, namely 1, 3, and 5 plants per hill. Good ears were selected from all three plats. In 1905 seed from each plat was planted at all three rates. We have selected seed continuously from each rate since 1905. The following table summarizes results to date.

Fig. 8. Average sample of corn grown 1 plant per hill.
Fig. 9. Average sample of corn grown 3 plants per hill.
Fig. 10. Average sample of corn grown 5 plants per hill.
The ears are classed in five groups according to weight. The cards show the weight in ounces. A large share of the ears weigh 12 ounces or over when only one plant is grown per bill, while very few attain this weight when five plants per hill are grown. In the latter case most of the ears weigh 6 to 8 ounces.

TABLE XII.—Summary of yields from different rates of planting
for three years (1906-07-08) according to origin of seed.

Conditions under which
seed was grown
1906
yield
Bushels
1907
yield
Bushels
1908
yield
Bushels
Average
yield
Bushels
One plant per hill 64.5 65.3 55.6 61.8
Three plants per hill 66.0 66.1 54.6 62.2
Five plants per hill 70.3 67.1 55.8 64.4

The average yield for the three years shows a decided advantage in favor of selecting seed from the thicker planting, altho the difference has grown less each year. The experiment must be continued some years, before final conclusions can be drawn.


Bul. Agr. Exp. Sta. Nebraska, 127. p. 21 (1912)
COMPETITION IN CEREALS
E. G. Montgomery

Corn has always been grown rather thin, so the plants are free from competition to a large extent. Natural selection through competion has not been effective. In order to secure data on the effects of competion in corn a series of plats were started in 1905, using Hogue's Yellow Dent corn and planting at 1, 3, and 5 grains per hill. Each lot has been planted continuously at the same rate since, the results for three years being given in Negraska Bulletin 112. In 1910, after five years continuous selection, the following results were secured:

Rate at which continuously
planted in past
Rate planted
in 1910
Yield per acre
Grains per hill Grains per hill Bushels
1 3 59.7
3 3 61.3
5 3 65.7

This shows a gain of 6 bushels per acre, or 10 per cent, as a result of growing the seed under competitive conditions.


Productive Farm Crops pp. 60-62 (1916)
SELECTION AND CARE OF SEED CORN
Edward Gerrard Montgomery

2Nebraska Agricultural Experiment Station Bulletin 127, p. 21, 1912.

The careful selection of seed corn seems important for two reasons: (1) In practically all the region north of the Ohio River it is necessary to see that corn matures well, while at the same time maintaining the size of the ear. (2) Since corn plants are spaced wide apart (as compared with small grain which is sown thickly), the plants are largely relieved from the effects of "natural selection," and so "artificial selection" must be practised to maintain the crop. Natural selection can be secured by very thick planting, and results at the Nebraska Station indicate that a more vigorous type of corn can be developed under thick planting than under thin planting. For several years corn was grown continuously, in one case, with only 1 stalk per hill; in another case 3 stalks per hill were grown continuously; and in a third case 5 stalks per hill were grown. In the thick planting only the strongest stalks could produce good ears. The yields produced in 1911, after six years of natural selection, when seed from each case was planted at the normal rate (3 stalks per hill), were as follows2:

Results from Seed Selected from Thick and Thin Plantings


Origin of seed
Yield when planted
3 grains per hill.
Bushels per acre
One plant per hill 39.8
Three plants per hill 43.7
Five plants per hill 48.1

Combined data from the above reports

Conditions under which
seed was grown
1906
yield
Bushels
1907
yield
Bushels
1908
yield
Bushels
1909
yield
Bushels
1910
yield
Bushels
1911
yield
Bushels
One plant per hill 64.5 65.3 55.6 59.7 39.8
Three plants per hill 66.0 66.1 54.6 61.3 43.7
Five plants per hill 70.3 67.1 55.8 65.7 48.1
Ave. yield in Nebraska*   25.77 28.17 26.18 27.13 21.45

*Data for average yield calculated from Nebraska Blue Book, 1920. p. 440

1911 was a particularly bad year for corn in Nebraska due to heat, drought and frost; 1910 was the best since 1906 for the U.S. in general.