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is coming, but after it is well up. When planted in drills it is best to harrow crosswise of the drills instead of with drills. When harrowing with the drills a harrow tooth will sometimes get started down a row and drag out the plants for some distance. In place of the smoothing harrow, the weeder or Gould harrow (A) may be used.
300. Depth of Planting.
—Maize may be planted
• r 11 Tools for stirring soil before or soon after maize is up. A. homemade
rainfall was . . .. ... .. . r
harrow, consisting of three pieces of 2x4, each seven feet four about tWO-thirds inches long, and eighty sixty-penny wire spikes. Traces of one horse j . to be hitched directly to flexible attachments indicated In order to
norma , W give harrow vibratory motion; B, weeder; C, adjustable smooth
inches gave the ing harrow,
best results. At the Illinois Station the average yield during 1 Ohio Rpt . 1890, p. bj.
five years "was as follows: One inch deep, 78 bushels; two inches deep, 72 bushels; three inches deep, 65 bushels; four inches deep, 69 bushels; five inches deep, 61 bushels; six inches deep, 60 bushels.1 This experiment was on soil much more favorable to deep planting than the average. In three years the best results were obtained at one inch, one year at four inches, and one year at six inches, this last being due to an exceptional period of drouth subsequent to planting. At the Ontario Agricultural College during four years, better yields were obtained at two and three inches deep than at shallower or deeper planting.* At the New York Station planting between two and eight inches deep caused a loss of seed germination as compared with shallower planting, but the yield per stalk was about the same at all depths.8
When planted by machinery, it is usually necessary to plant some of the seed somewhat deeper than one inch in order that all may be covered an inch deep. Hence the desirability of a uniform seed bed. Where it is the practice to harrow the land after planting it is probably better to plant deeper than one inch so as not to move or drag out the hills. The depth of planting has merely to do with the plant getting properly started. If the seed germinates equally well, no difference in yield need be expected on account of depth of planting. Nothing is gained by deep planting, unless necessitated by dryness of soil or practical considerations just mentioned. It only requires of the plant greater time and effort to reach the surface. The depth of roots is not materially affected by depth of planting. (52)
301. Listing.—There is a method of planting known as listing practiced in those States where the soils are friable and the rainfall scanty. Shelton wrote in 1888: *
1 m, Bui. 31, p. 353.
i Ont . Agr. and Expt. Farms Rpt. 1902, p. 133.
"At the present time nearly or quite three-fourths of Kansas corn is raised by the method known as listing; which, I may say in explanation, consists of drilling ihe seed in the bottoms of deep furrows struck at the usual intervals in ground not otherwise plowed.
'' V is claimed that listed corn endures dry weather much better than the surface planted; that it gives increased yield and this especially that the labor of growing a crop of corn is reduced one-fourth to one-third by the new method."
Kansas Station has reported six, Oklahoma Station two tests of listed maize as compared to that surface planted, as follows:
Five out of the eight trials of listed maize gave the best results and on the average of the eight trials the yield was six
per cent greater than when surface planted.
At the Illinois Station1 maize listed on fall plowed land gave a
Combined sulky lister and planter; makes furrow in unplowed ground, drops and covers seed at the same time. In some cases disks are used in place of shovels to cover the seed.
1 III BuL 37, p. 24.
'yield of fifty-one bushels as compared with fifty-six bushels on an average of ten adjacent plats when surface planted.
302. Time of Planting.—The soil should be at least 6o° F. at the depth of the seed before maize is planted. But it is not enough to consult the thermometer; the almanac should also be consulted. A change in the weather may follow even after the temperature of the soil is 60° F. The old Indian sign, which is to plant maize when the leaves of oak trees are as big as a squirrel's ear, is not much at fault. The best date of planting will of course vary largely with the season. The following table gives the best dates as determined at the stations indicated, as well as indicating the period over which the test was made.
There is fairly good evidence that in the main maize belt there is a period of three to four weeks within which the time of planting does not materially affect the yield. At the Illinois Station, for example, while the best results during an average of eight years were obtained from May 1 ith to May 18th, there was but little difference in yield from May 4th to June 1st. Very early planting, however, has been shown to require more cultivation to keep the land free of weeds. On the other hand, it is not wise to delay planting when the conditions are favorable for fear that subsequently climatic conditions may be such as to prevent the planting at the theoretically best time. Where maize is planted on old sod land, it is frequently advisable to delay planting in order to avoid cut worms and other allied insects. (329)
303. Rate of Planting.—In securing maximum yields of grain and stover very much depends upon the rate of seeding and the uniformity of distribution. The thickness of planting depends upon the soil, the climate, the variety and the purpose for which it is grown. In some of the Southern States maize is planted in hills five feet apart and one stalk produced per hill. In the New England States it is planted 3.5 feet apart and three to four stalks are raised per hill. In one experiment at the Georgia Station1 a larger yield of maize was obtained where 2,184 stalks were raised per acre than by thicker planting. In another experiment at the Connecticut Station2 a greater yield of grain and of water-free fodder was obtained with 21,780 stalks per acre than by thicker or thinner seeding. In other words, the best results with dent maize were obtained in Connecticut with ten times as thick planting as in Georgia. These results are doubtless unusual, but they indicate possible extremes.
The Illinois Station tested for three years six rates of seeding ranging from 5,940 grains to 47,520 grains per acre; and for five years rates ranging from 9,504 grains to 47,520 grains per acre. Five plats of each rate were planted each year under different methods of distribution. The size of the whole plant and of the ear increased uniformly as the planting became thinner. The proportion of ears to stalks also increased. The total weight of fodder increased uniformly as the planting increased in thickness. The total weight of grain was greatest two years when 23,760 grains were planted; two years when 11,880 grains were planted, and one year when 9,504 grains were planted. In this last instance the total yield was small, the season being exceptionally unfavorable for maize. The
1 Ga. Bui. 10, p. 148. 2 Conn. Rpt. 1889, p. 16.