Part 1

Transcriber Note

Text emphasis is denoted as _Italics_. Whole and fractional parts of numbers as 123-4/5.

SWEET CLOVER

HARVESTING AND THRASHING THE SEED CROP

H. S. COE

Assistant Agrononmist, Office of Forage-Crop Investigations

FARMERS' BULLETIN 836 UNITED STATES DEPARTMENT OF AGRICULTURE

Contribution from the Bureau of Plant Industry

WM. A. TAYLOR, Chief

Washington, D. C. July, 1917

Show this bulletin to a neighbor. Additional copies may be obtained free from the Division of Publications, United States Department of Agriculture

WASHINGTON : GOVERNMENT PRINTING OFFICE : 1917

SWEET CLOVER should be cut for seed when three-fourths of the seed pods have turned dark brown to black. At this time some flowers and many immature pods will be found on the plants, but the field will have a brownish cast.

Sweet-clover seed pods shatter badly when mature. For this reason every precaution should be taken to cut the plants at the proper stage and to save as much of the shattered seed as possible.

Shattering may be reduced to a minimum by cutting the plants when they are damp from rain or dew.

No machine thus far placed on the market has given entire satisfaction in cutting sweet clover for seed.

The ordinary mower should not be used for harvesting the seed crop. The seed crop is usually cut with a self-rake reaper, grain binder, grain header, or corn harvester. The self-rake reaper and the grain binder have been most satisfactory.

The seed crop should be stacked unless it can be thrashed within two weeks after cutting.

Much shattered seed will be saved if a wagon with a tight floor is used for hauling the plants. If the wagon bed is not tight it should be covered with a tarpaulin or canvas.

The seed may be flailed from the plants, as is customary in the South, or it may be thrashed with a grain separator or clover huller, as is the practice in the North.

The ordinary grain separator may be adjusted so that it will hull 90 per cent of the seed.

Sweet-clover straw has considerable feeding value.

SWEET CLOVER: HARVESTING AND THRASHING THE SEED CROP.[1]

[1] This bulletin discusses only the harvesting and thrashing of the sweet-clover seed crop. The growing of sweet clover and its utilization are discussed in Farmers' Bulletin 797, entitled "Sweet Clover; Growing the Crop," and Farmer's Bulletin 820, entitled "Sweet Clover: Utilization," respectively.

CONTENTS.

Page.

The crop to harvest for seed 3

Time to cut the seed crop 4

Loss of seed from shattering 4

Machinery used for harvesting the seed crop 5

Stacking the sweet-clover seed crop 17

Thrashing the sweet-clover seed crop 18

Yields of sweet-clover seed 21

Sweet-clover straw 23

THE CROP TO HARVEST FOR SEED.

White sweet clover and biennial yellow sweet clover are harvested for seed the year following seeding. In localities where those species will produce two cuttings the second year, either the first or the second crop may be harvested for seed. As the plants die when mature, only one cutting will be obtained if the first crop is permitted to ripen. It is becoming a general practice in many sections of the country to utilize the first crop of the second season for pasture, ensilage, or hay, and the second crop for seed. As a rule, this is the most profitable and economical way to handle sweet clover, as the first crop will produce an abundance of nutritious pasturage or from 6 to 10 tons of ensilage or 1 to 3 tons of hay to the acre. The second crop seldom grows more than 4 feet high when the first crop is pastured or cut. The shorter growth of the second crop is a very desirable feature, as it may be cut with a grain binder without difficulty. When the first crop of white sweet clover is permitted to mature, the plants often make so large a growth that it is very difficult to handle them with ordinary farm machinery. This trouble is experienced more often in humid regions than in semiarid sections.

As biennial yellow sweet clover seldom grows as tall as the white species, little difficulty is experienced in cutting the first crop of the second year for seed with a grain binder. Annual yellow sweet clover, or sour clover, is seldom grown for seed, as a sufficient quantity to supply the market is obtained from the screenings of wheat grown in the Southwest.

Sweet-clover seed ripens irregularly and shatters badly when mature. On this account much seed is lost before and during harvest, and ordinary harvesting machinery has not been entirely satisfactory for handling the crop.

TIME TO CUT THE SEED CROP.

Opinions of extensive growers of sweet clover differ as to the proper stage at which to cut the seed crop. Some believe that it should be cut when the pods on the lower branches have turned dark brown to black, while others maintain that it is best to wait until the seed on the upper portions of the plants is mature. The time of cutting the seed crop should be governed largely by the machinery which is to be used. If the plants are to be harvested with a self-rake reaper or a grain binder, they should be cut when approximately three-fourths of the seed pods have turned dark brown to black. At this time some flowers and many immature pods will be found on the plants, but the field will have a brownish cast. If the crop is not cut until the seed pods on the uppermost branches have matured, most of the pods on the lower branches will have shattered.

It is the practice in regions where a grain header is employed to permit the plants to become somewhat more mature before cutting the seed crop than in sections where other machines are used. More seed is shattered when the plants are cut at the latter stage, but this is not necessarily a loss, as the grain header is employed for the most part in semiarid regions, where the shattered seed is depended upon to reseed the land.

LOSS OF SEED FROM SHATTERING.

From one-fifth to three-fourths of the total seed yield of sweet clover is lost from shattering. The percentage of the loss which occurs before harvesting will depend largely on the time the crop is cut. Much seed may be lost if harvesting is delayed for only a few days, and many fields have been observed in which at least 90 per cent of the seed had shattered in less then two weeks after the time the plants should have been cut.

The percentage of seed which is lost in harvesting will depend largely upon the manner of handling the crop. The binder or header may be equipped at a small cost, so that much of the seed which ordinarily is lost while cutting may be saved. Much shattered seed will be saved by using wagons with tight platforms or platforms covered with canvas. All unnecessary handling should be avoided.

Shattering may be reduced to a minimum by cutting the plants when they are damp from rain or dew. It is the practice in some regions to cut in the early morning or late evening, but this procedure will apply only to small acreages, since it is necessary to cut the crop as soon as possible when it reaches the proper stage for harvesting. It is a good practice to cut sweet clover at night, as the plants usually are damp at that time.

MACHINERY USED FOR HARVESTING THE SEED CROP.

No machine thus far manufactured has given entire satisfaction for cutting the sweet-clover seed crop. On account of the ease with which the pods shatter, it is a question whether any machine can be devised which will handle this crop without the loss of some seed. It is possible and practicable, however, for farmers at a small cost to equip their binders with pans and guards, so as to save most of the seed which otherwise would be lost.

THE ORDINARY MOWER.

The ordinary mowing machine is one of the most unsatisfactory devices used for harvesting this crop, as the subsequent handling necessary to place the plants in windrows or cocks causes much of the seed to shatter. The use of this machine for this purpose should be avoided whenever possible.

THE SELF-RAKE REAPER.

The self-rake reaper is one of the most efficient machines employed to cut sweet clover for seed. (Fig. 1.) This machine deposits the newly cut plants with the tops all turned one way in gavels or bunches at the side, so that the horses do not trample them on the next round. A high stubble also may be left, thereby reducing the weight and bulk of the plants which must be hauled to the thrashing machine.

It is the custom in some localities to leave the gavels to cure as dropped by the reaper on the ground, while in other sections they are placed in cocks that weigh about 300 pounds each when cured. If the gavels are to be placed in cocks, this should be done immediately after cutting, as the plants will be somewhat green and tough at this time and fewer pods will shatter than when the plants are permitted to dry before handling. When the crop is to be hauled to the thrashing machine on wagons it is best to permit the gavels to cure as dropped by the reaper, as it will then be possible to pitch them on the wagon with a large 4-tined fork. If the crop is to be hauled to the thrashing machine on large sleds, which is the practice in western Kansas, less seed will be lost from shattering if the gavels at the time of cutting are placed in cocks of such a size that they may be put on the sleds entire by two men lifting from opposite sides of the cock with 4-tined forks. The sleds used for this purpose usually are 12 by 20 foot in size, made of matched flooring and with 6 to 12 inch sides. (Fig. 2.) Matched or tight floors are necessary, so that all seed which shatters may be saved. These would not be so essential, however, if the sleds were covered with a tarpaulin or canvas. From the standpoint of saving shattered seed, this method of hauling the crop from the field to the thrashing machine is possibly the most economical thus far used. It is estimated that at times as much as one-third of the seed yield is collected from the floors of the sleds. It would be a good plan to replace the runners of the sleds with very low trucks, as this would lighten the draft considerably.

When sweet clover is cut with a self-rake reaper the crop is thrashed directly from the field. From 7 to 10 days of good haying weather in sufficient to cure the plants in the gavel or cock. Thrashing should be done as soon as possible, much seed is shattered by rains and winds. While a self-rake reaper is used to some extent in different sections of the country, it is used most extensively in the western North-Central States, and especially in western Kansas.

THE GRAIN BINDER.

A grain binder is employed extensively for cutting the sweet-clover seed crop. (Fig. 3.) The general use of this machine in many sections of the country is due to the fact that it is found on most farms and therefore causes no outlay of money, rather than because of its efficient work. It is not so efficient as the self-rake reaper unless it is equipped with pans and guards to save the seed which shatters.

It is possible to equip the grain binder with pans and extensions to the rear elevator plate and binder deck, so that at least 95 per cent of the seed which shatters when the crop is cut may be saved. Those pans and extensions may be made out of ordinary galvanized metal and strap iron. The galvanized metal may be purchased at any tin shop or hardware store, and if sufficient strips of iron can not be found around the farm for this purpose strap iron may be purchased at any blacksmith shop. The material for those pans and extensions should not cost more than $4.50 or $5, and it should be possible to have them made complete for $8 or $10, including material. Unless there are a forge and drill on the farm it will be necessary to have the braces and supports for the pans made at a blacksmith shop. The strap iron used in connection with the pans may vary in size, but for the most part it need not be heavier than one-eighth inch in thickness, and seven-eighths inch in width. The supports for the pan under the binder deck preferably should be one-quarter inch thick, as this pan will have much more strain on it than the pans under the elevators. Where bolts are to be used, ordinary stove bolts will suffice.

The plans for making the pan which should be placed under the opening between the platform and the lower elevator are illustrated in figure 4. The material to be used for this pan should be cut to conform to the size and shape shown in figure 4, _A_; the sides should then be bent upright along the dotted lines, so that the pan will be 18 inches wide at the top. One end, which should be solid, may be made so by bending the center portion upright and then bending the sides against it. The side and center pieces should be riveted together. (Fig. 4, _C_.) Any suitable door which will prevent seed from falling out of the pan will suffice for the other end. A door is highly desirable, so that the seed may be removed more easily when the pan is full. A convenient type is shown in figure 4, _E_. A top view of the pan when completed is given in figure 4, _B_. It will be necessary to brace the pan, and this may be done by riveting strips of strap iron, preferably one-eighth inch thick and one-half inch wide, on the outer edges of the sides.

This pan is held in position by two supports made of strap iron, preferably seven-eighths inch wide and one-eighth inch thick, which have been bent to conform to the outside of a cross section of the pan. (Figs. 4, _C_, and 5, _B_.) The ends of these supports which fasten under the platform should be bent to a sharp angle and the tip of each slightly flattened, so that they may be pushed between the angle bar at the end of the platform and the bottom of the platform. The other end of each support should have a hole drilled in it, so that it may be bolted to the stirrups, which should be made to hook over the inside sill. (Figs. 4, _C_, and 5.) These supports should be placed about 6 inches from the ends of the pan and riveted or bolted to it. This will serve to brace the pan and to hold it in place. The pan may be attached to the machine by hooking the supports over the angle iron on the bottom of the platform and by bolting them to the stirrups on the sill. By supporting the pan in this manner it may be easily and quickly attached or removed.

The pan to be placed under the deck of the machine will serve to collect the seed which is shattered on the deck and the extension to the deck. The plans for making this pan are shown in detail in figure 6. The material should be cut along the solid lines and of the size designated in figure 6, _A_. The sides of the pan should be bent upward on the dotted lines, so that the pan will be 24 inches wide at the top. The ends should then be made in the manner described for the pan which is placed under the opening of the platform and lower elevator. A door may be put in the rear end of this pan if desired; but this is not necessary, as no trouble will be experienced in removing the seed. Figure 6, _B_, gives a top view of the pan when completed and also a portion, of the guard which serves to direct into this pan the seed which shatters on the deck. This guard is shown in detail in figure 7. As this pan is larger and heavier than that placed under the lower elevator, not only should it have strips of iron riveted to the outer edges of the sides, but two cross braces also should be employed. Those may be fastened to the strips of iron supporting the sides of the pan and should be about 12 inches from the ends of it. This pan is supported by two strips of strap iron bent to conform to the outside of a cross section of it and hook over the binder pipe under the deck and bolt to stirrups placed on the outer sill of the frame. Each support may be made from one strip of strap iron. It may be necessary to bend the ends of the supports which hook over the binder pipe in opposite directions. Both ends of the supports which hook over the binder pipe may hook outward, as shown in figure 7, _C_, or the rear support may hook inward, as illustrated in figure 5. It is not absolutely necessary that those supports of the pan hook in opposite directions on the binder pipe, yet when this is done it will make the pan more rigid. The pan may be attached by first hooking the supports over the binder pipe underneath the deck and then bolting the other end of the supports to the stirrups on the outer sill. The pan should be fastened to the supports. A cross section of this pan, the supports for it, and the stirrups which hook over the sill are shown in figure 7, _C_.

If this pan extends beyond the deck so that the seed which is shattered on the deck will drop directly into it, the bundles when released from the packers will strike the pan. For this reason it is necessary to place a guard at the end of the deck, so that the seed which falls on the deck will be directed into the pan. This guard, as shown in figures 5 and 7, consists of a piece of galvanized metal, to the upper side of which has been riveted a strip of iron. The upper side of this guard should be bent slightly inward at the lower edge of the strip of iron and placed in such a position that it will be approximately 1-1/2 inches beyond the lower end of the binder deck and extend from 1 to 1-1/2 inches above the deck. If it is placed at right angles to the deck and no higher than 1-1/2 inches above it, it will not interfere with the bundles as they are released from the packers. This guard should be supported by two angles of strap iron, as shown in figure 7, _D_. Those braces are bolted to the supports of the pan, and the guard is bolted to the braces. As this guard should extend a little below the supports of the pan, so as to prevent the wind from blowing the seed over it, it is necessary to cut slots in the guard so it will fit over the supports. The ends of this guard should be rolled slightly inward, so that the seed falling close to them will be directed into the pan. When the extension to the binder deck is placed in the proper position, the seed collected by it will be directed against the guard and then into the pan below.

The extension to the elevator should be bolted to the rear elevator plate. This extension should be so wide that the tops of the plants will not reach beyond it. The details for this extension are shown in figure 8. The outer edge and lower end of this extension should be bent upward and slightly inward, so that the seed which falls upon it will be directed to the opening between the platform and lower elevator, where it will fall into the pan beneath. The curved edge of the lower part of this extension should be flattened as much as possible, so that it will not interfere with the upper portions of the plants as they pass from the platform to the elevators. The opening must be sufficiently large, however, to permit small branches and racemos which fall upon the extension to pass into the pan. The angle of the lower portion of it must be large enough to permit the seed to run directly into the pan below. If this portion is sloped from the seat pipe to the opening between the platform and the lower elevator no trouble will be experienced. This extension may be bolted to the machine by drilling holes in it to coincide with those in the elevator plate.

It is necessary to widen the binder deck, so as to save the seed which is shattered from those portions of the plants which extend beyond it. This may be done by bolting to the rear end of this deck an extension, as shown in detail in figure 9. This extension may be made from one piece of galvanized iron, which should be cut along the solid lines and of the size shown in figure 9, _A_. It should be bent upward and slightly inward at the dotted lines shown in this figure. The extended strips, as shown in figure 9, _B_, should be riveted to the main part of the extension. When this is done a trough will be formed along the side and lower end of it, so that all seed which shatters upon it will be directed into the pan below the deck. The object in riveting the extended strips at the end of the extension to the main part is to prevent the tops of the plants from catching in the trough when the bundles leave the packers. It may be necessary to fasten a brace to the bottom of the deck to support this extension. This can be done, however, by using a strip of strap iron or wood. The upper end of this extension should be bent to fit under the upper end of the one attached to the elevator plate, so that the plants will not be hindered in passing from one to the other. Both extensions may be braced strongly at the top by fastening them to a right angle of iron or wood.

A grain, binder equipped with the pans and extensions herein outlined is shown in figure 10.