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producing an unfavorable seed-bed condition. Thus during the interval between crops, it is often advisable to use the Acme harrow or the disk, or spring-tooth harrow, in order to keep the surface of the soil open and mellow.

A new method for preparing the seed-bed is now coming into general practice in Western Kansas. In preparing land for wheat, the plan is to list the ground with the ordinary corn lister as soon after harvest as possible. The lister furrows are run about three to three and a half feet apart, very much the same as when the lister is used for planting corn. Later, when the weeds have started, the soil is worked back into the lister furrows by means of a harrow or disk culti

vator.

Several cultivations are usually required by the harrow, and disk harrow, in order to level the field and bring it into good seed-bed condition. Once over with the disk cultivator is usually considered sufficient, the further work necessary to prepare the seed-bed being given with the common harrow or other cultivating implement.

In a dry climate this method of preparing the seed-bed has several advantages, as follows:

The cultivation of the land soon after harvest tends to conserve the moisture already stored in the soil. The furrowed land is in good condition to catch and store the rain and the later cultivation clears the land of weeds and volunteer wheat and leaves a mellow soil mulch to conserve the moisture which has been stored in the subsoil. The early and continued cultivation of the soil favors the action of the bacteria and the development of available plant food.

By practicing this method the farmer may cultivate a larger area early in the season when the soil is in good condition, when if it had been necessary to plow the whole area, some of the land might become too dry to plow well. Likewise the later plowing leaves the soil too loose and not in good seedbed condition. In preparing land for corn, the listing may be done late in the fall or during the winter, or early spring. The usual plan being to split the ridges with the lister later in the spring when the corn is planted. It is advisable to harrow the listed field once or twice before planting to destroy weeds, or prevent soil drifting and to preserve a mellow soil mulch to conserve the water which has been stored in the subsoil. In preparing land for corn, the early listing has proved equal to early plowing and superior to early disking, as shown by the experiments at the Kansas Station.

In the drier portions of the great plains area and throughout the mountain states, where dry farming is practiced, the annual rainfall is not sufficient to produce a crop every year, and it becomes necessary to practice a system of summer fallowing every third or fourth season, or in alternate years in localities of least rainfall, in order to store moisture and develop plant food and thus insure the production of a profitable crop each year.

Deep plowing either in the fall or spring, and frequent surface cultivation as described above is the method of summer fallowing which has given the best results at the Montana, Western Nebraska, and Western Kansas Experiment Stations.

The weeder is better adapted for harrowing wheat and other small grains than the common harrow, but the harrow may be used when the ground is firm. I question whether it is necessary or advisable as a rule to harrow wheat if due precautions have been taken in preparing the seed-bed.

Under certain conditions, where heavy rains firm and puddle the soil, it may be advisable to harrow, but very young grain may be injured by harrowing, and after the wheat covers the ground, harrowing is unnecessary. The harrowing of wheat at regular intervals at the Kansas, Nebraska and Montana Experiment Stations has not resulted favorably. Without question, the proper preparation of seed-bed is a much more important factor in the growing of small grains, than the cultivation after seeding.

While it is a disputed point among authorities whether it pays to harrow wheat and other sowed crops, there is no difference of opinion regarding the necessity or value of frequent cultivation of corn and of all other crops usually planted in rows. Regarding the depth and frequency of cultivation desirable, I favor rather deep cultivation in our drier, hotter climate, and after every hard rain, if possible, or at least sufficient to keep the weeds in check.

It is not necessary or practicable to attempt to cultivate after every rain and there is no virtue in the admonition "Keep the Cultivator going in a dry time." If the soil has been well stirred and the mulch is of sufficient depth, to cultivate again would be loss of time and might do actual harm by drying out the deeper portions of the soil mulch and also causing a too fine and dusty condition of the surface soil, unfavorable to the absorption of moisture when the rain

comes.

It is not necessary to have extra machinery in order to successfully practice the system of culture outlined above. The only implements required or recommended which are not in general use on every well equipped farm, are the subsurface packer and the weeder.

The principles stated above have been known and practiced more or less for a long time and are mostly included in the "Campbell" system of culture. H. W. Campbell was among the early apostles of dry farming in the West, and has perhaps done more to call the attention of western farmers to the necessity and advantages of thorough cultivation of the soil than any other investigator. Scientific farming pays, everywhere. I believe in the practicability of thorough tillage and good cultivation on every farm, and the increase in crops by such farming will more than pay for the extra labor. But the great problem in Western agriculture today is not how to get larger crops out of the soil for a few years, but rather how to produce paying crops every year and at the same time maintain the fertility and productiveness of the land.

Simple tillage will not maintain soil fertility. It becames necessary finally to replace the plant food, exhausted by the continuous growing of crops, with the application of manure, or chemical fertilizers, and by green manuring and the rotation of crops, in which the legume crops, such as alfalfa and clover are introduced in order to restore again the nitrogen and organic matter, the supply of which has only become more rapidly reduced because of intensive cultivation. There is little question regarding the value and even the necessity of the summer fallow in the drier areas of the West. The tests at a number of Western stations and the general experience of farmers prove this; yet there are serious objections to the continued practice of bare summer fallowing.

First, there is the tendency for the soil to waste by drifting in strong winds and by washing away in heavy rains.

Second, summer fallowing with frequent cultivation hastens nitrification and decay, thus more rapidly exhausting the organic matter in the soil.

It is possible for the soil to become more rapidly exhausted in fertility by alternate bare summer fallowing and cropping than by continuous cropping. At least the bare summer fallow does not add any fertility to the soil. In order to maintain the productivity of our Western lands, it will become necessary to add fertility to the soil preferably during the year of fallowing.

I am beginning the practice of a method of green manuring and partial summer fallowing, which I believe to be superior to bare summer fallowing and which will largely overcome the objections to summer fallowing.

The plan is to plant some fall crop or early spring crop and plow it under late in May or early in June, practicing a summer fallow with surface cultivation for the rest of the season, until seeding time.

Certain crops adapted to the West are being tested for this purpose with some degree of success. The more promising are sweet clover and sand vetch for fall seeding and field peas for early spring seeding. These crops are hardy, rapid growers, and somewhat drouth resistant and may be used also in part for pasture, thus giving some return other than their fertilizing value. Some experiments have already been made at the Hays Station in Western Kansas and the yields of wheat secured from the green-manuring summer fallow compare favorably with the yields from the bare summer fallow. And in my judgment, this method of fallowing will soon be generally adopted and will solve the problem for a long time at least, of increasing the organic matter and maintaining the productiveness of our western lands.

This method of green manuring and rotation of crops will largely prevent soil drifting, the control of which is a very serious problem in western agriculture. Our experience at the Station at Hays has demonstrated also that large areas in wheat may be protected and largely prevented from being injured by the drifting of soil within the field itself. The spreading of straw or coarse manure and packing the straw into the soil with the subsurface packer was the most effective means employed for protecting the fields from injury by winds last spring (1911). The subsurface packing alone helped to prevent the starting of the drifting soil within the field, but was not very effective in preventing the soil from adjacent fields from sweeping over the wheat field, but the straw covered area actually stopped the drifting soil, causing it to lodge, and thus protected the field beyond the straw barrier.

It is quite as necessary, however, to prevent the drifting of adjacent fields, as to protect the wheat field itself. This may be done by early listing or disking of the fall plowed fields and corn or kaffir stubble fields which are almost sure to drift in a violent wind, when the soil is very dry at the surface. Disking or other surface cultivation will prevent drifting of soil for a time, until the looser portion dries out, then the soil can only be held by deeper cultivation as by listing

or plowing. For putting the surface in the best condition to resist wind force a long time, I prefer to break the ground with a lister, forming deeper furrows and higher ridges than may be prepared with the disk or cultivator.

During the season of 1911, which has been extremely dry and hot, the wheat on summer fallow at the Station at Hays made a larger growth and a much better showing in the early part of the season than other wheat, but before the crop matured the conditions of drouth and heat became so severe that the wheat was greatly injured, and the summer fallow produced a little larger yield but a poorer quality of grain than was secured from other land not summer fallowed.

The yields compare approximately as follows: Summer fallowed, five bushels per acre. Not summer fallowed, two bushels per acre. In other localities in Western Kansas where the rain was greater and the condition less severe, the summer fallow made a better showing.

It was also true last season, at the Western Kansas Station, that the extra cultivation in preparing the seed-bed was without beneficial effect, in producing a larger yield of wheat. However, in ordinary seasons the reverse has usually been true; summer fallow has given much larger yields than continuous cropping, and early plowing and extra cultivation have usually given a marked increase in yield in the comparative tests which have been carried on at the Experiment Stations, both at Manhattan in Eastern Kansas and also at Hays in the western third of the state. At the Manhattan Station the careful preparation of the seed-bed was very effective in increasing the yield of wheat in 1911, even doubling and trebling the crop. The results of much of this work are summarized in the succeeding pages.

Three general methods of tillage for preparing the land for winter wheat are practiced in this state, namely: plowing, listing and disking. There may be variations of these three methods; as early plowing, shallow plowing, deep plowing, single listing, double listing, disking without plowing, disking before plowing, little cultivation after plowing, frequent cultivation after plowing, etc., and local conditions may determine which method is the best. That certain methods are superior to others may be readily shown by comparative trials which have been carried on at the Kansas Station during the past two years. These experiments include the several general methods of tillage named above with variations as described in Table I, which gives the yield of wheat per acre and other data determined by those experiments. This work was done at the State Experiment Station at Manhattan, located in the middle eastern part of the state.

TABLE I. METHODS OF PREPARING SEED-BED FOR WHEAT.†

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1See Kansas Experiment Station Circular No. 2 and Bulletin No. 176. Disked only once just previous to sowing wheat.

Much of it was done by myself or under my direction during eight years of service as agronomist at that station.

Observe that the largest yields have been secured, as an average for the three years from July and August plowing seven inches deep. The July listing has ranked next to early plowing, but yielding on the average nearly five bushels less wheat per acre than early plowing, or a decrease in yield of 14 per cent. The decrease in yield from listing was less in the dry year of 1910-11.

All of the higher yielding plots were cultivated at intervals after plowing or listing with the harrow, disk or Acme. Thus the weeds were destroyed, the soil was well pulverized and well settled and put into excellent seed-bed condition by the first of October, when the wheat was planted.

One or two cultivations after August plowing, at an extra cost of thirty-five cents to fifty cents per acre, has given an average increase in the yield of wheat of three and a half bushels per acre. Land disked before plowing, July 15, and plowed August 15, 1910, gave an increase in yield of five bushels per acre in 1911.

Deep plowing in July, 1910, gave nearly five bushels more wheat per acre in 1911 than shallow plowing. As an average for the several seasons, the September shallow plowing has given a little larger yield than the deeper plowing.

The beneficial effect of early plowing and of frequent cultivation after plowing in preparing the seed-bed for fall wheat was most marked in the dry season of 1910-11, when plowing a month later each time decreased the yield at the rate of ten and one-half to twelve bushels per acre.

The preparation with the lister has proved to be a little less effective than early plowing, but has given better results than early disking followed by plowing a month later. Filling the furrows by harrowing, versus splitting the lister ridges and leveling with the harrow have given about equal results. The second listing is not necessary and makes the preparation somewhat more expensive. Preparing the seed-bed by listing and harrowing is cheaper than early plowing and frequent cultivation. The largest yield and largest net income, however, has been secured from early plowing followed by sufficient cultivation to kill weeds and maintain a mellow soil mulch.

Preparing the seed-bed by disking has given the lowest yields and least income. The disked land has produced on the average each year eighteen bushels less wheat per acre than early plowing. That is, the well prepared seed-bed has given 114 per cent the greater vield. or more than double the yield of the poorly prepared seed-bed, and at very little greater cost of preparation.

The next lowest ield was produced by late plowing, a week or two before the wheat was planted. The average decrease in yield from September plowing compared with July plowing was over twelve bushels per acre per annum, or early plowing increased the yield fifty-four per cent. In the drier seasons of 1910-11 the difference was greater, the early plowing producing more than double the yield received from the late plowing.

"Disking in" wheat in the dry season resulted in an almost complete crop failure, giving a small yield of only four bushels per acre; compared with thirtyeight bushels per acre produced by deep early plowing. This is certainly a marked example of the value of "proper" cultivation in preparing the seed-bed for wheat.

The seed-bed for corn should be deeper and more mellow than the seed-bed for wheat, and the early cultivation of the corn land previous to planting may cause a marked increase in yield, as shown by experiments which have been recently completed at the Kansas Station. These experiments relate to different methods of tillage which may be practiced during the winter or early spring in preparing the seed-bed for corn, and include deep and shallow plowing, double disking, and listing, namely, plowing land into ridges with a double mold-board plow or lister.

In these experiments corn has usually been planted in listed furrows, except that the surface and lister methods of planting have been compared each year on the plowed plots. Table II gives the yield of shelled corn per acre secured by the continued practice of the methods described, for a period of six years. The average yield for three years (1906-08) and for six years (1903-08) is also given.

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While the relative yields vary somewhat from year to year, it is very clear that the early plowing and early listing have given increased yields of corn, ranging from six to twelve bushels per acre for the three years, and four to five bushels per acre as an average for six years.

As an average for three years the double disking and harrowing early in the spring has given an increased yield of five and one-half bushels of corn per acre. It will be observed that in the above comparison all of the corn was planted in listed furrows.

Comparing the two methods of planting it appears that the highest yield for three years was produced by listing in the early shallow plowed land: The average yield for six years, however, was 3.3 bushels per acre in favor of the surface method of planting.

The results may be explained by the fact that the seasons of 1904 and 1905 were very wet, hence there was less necessity of conserving soil moisture, and the early cultivation gave little benefit, while the lister method of planting was placed at a disadvantage. The method of planting corn in listed furrows is adapted to dry climate and warm soil. Corn planted in the bottom of a furrow four to six inches deep develops a deeper root system than surface planted corn; hence listed corn is not readily injured by drouth. The effect on the root system is shown by the study of corn roots made at the Station.*

* See Bulletins 127 and 147.

It is quite evident that the best method of preparing the seed-bed for corn and the best method of planting corn will vary for different climatic and soil conditions. Yet it is very important that the farmer test these methods and determine which is the better for his particular conditions, since the method of seed-bed preparation and the method of planting may be very important factors in securing large yields.

In the cultivation experiments carried on at the Station during the past six years the practice has been to "lay the corn by" with a final cultivation about the first of July. In these experiments the plan has been to cultivate duplicate plots by four different methods, as follows: shallow; deep; deep early and shallow late; shallow early and deep late. The shallow cultivation has been performed with the knife or gopher type of cultivator, while for the deep cultivation, the six-shovel cultivator has been used.

The plan has been not to cultivate excessively deep but only medium deep. three to four inches. The depth of the surface cultivation has averaged one and one-half to two inches. The corn has usually been cultivated four times each season, and the practice has been to cultivate by the same method twice in succession those plots in which the method of cultivation was changed during the season, that is, certain plots were cultivated shallow at the first two cultivations and deep at the last two cultivations, and vice versa. The yield of shelled corn each year and the average yield for seven years, by the different methods of cultivation, are given in Table III.

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