Part 1

Transcriber Note

Text emphasis is denoted as _Italic_.

SWEET CLOVER: UTILIZATION

H. S. COE

Assistant Agronomist, Forage-Crop Investigations

FARMERS' BULLETIN 820 UNITED STATES DEPARTMENT OF AGRICULTURE

Contribution from the Bureau of Plant Industry

WM. A. TAYLOR, Chief

Washington, D. C. May 1917

WASHINGTON : GOVERNMENT PRINTING OFFICE : 1917

SWEET CLOVER may be utilized for feeding purposes, as pasturage, hay, or ensilage. With the possible exception of alfalfa on fertile soil, sweet clover, when properly handled, will furnish as much nutritious pasturage from early spring until late fall as any other legume. It seldom causes bloat.

Stock may refuse to eat sweet clover at first, but this distaste can be overcome by keeping them on a field of young plants for a few days.

As cattle crave dry roughage when pasturing on sweet clover, they should have access to it. Straw answers this purpose very well.

An acre of sweet clover ordinarily will support 20 to 30 sholes.

On account of the succulent growth, it is often difficult, in humid climates, to cure the first crop of the second season into a good quality of hay.

When seeded without a nurse crop, one cutting of hay may be obtained the first year in the North and two or three cullings in the South. Two cuttings are often obtained in the South after grain harvest. The second year a cutting of hay and a seed crop usually are harvested.

Sweet clover should never be permitted to show flower buds before it is cut for hay. It is very important that the first crop of the second season be cut so high that a new growth will develop. When the plants have made a growth of 36 to 40 inches it may be necessary to leave the stubble 10 to 12 inches high.

In cutting the first crop of the second season it is a good plan to have extension shoe soles made for the mower, so that a high stubble may be left. In some sections of the country sweet clover as a silage plant is gaining in favor rapidly.

This crop has given excellent results as a feed for cattle and sheep. Experiments show that it compares favorably with alfalfa.

Sweet clover has proved to be a profitable soil-improving crop. The large, deep roots add much humus to the soil and improve the aeration and drainage. As a rule, the yield of crops following sweet clover is increased materially.

Being a biennial, this crop lends itself readily to short rotations.

Sweet clover is a valuable honey plant, in that in all sections of the country it secretes an abundance of nectar.

This bulletin discusses only, the utilization of sweet clover. A discussion of the growing of the crop may be found in Farmers' Bulletin 797.

SWEET CLOVER: UTILIZATION.[1]

[1] The growing of this crop has been discussed in a previous publication, Farmers' Bulletin 797, entitled "Sweet Clover; Growing the Crop."

CONTENTS.

Page.

General statement of the uses of sweet clover 3

Sweet clover as a pasture crop 4

Sweet clover hay 10

Sweet clover as a silage crop 20

Sweet clover as a soiling crop 22

Sweet clover as a feed 23

Sweet clover as a soil-improving crop 28

Sweet clover in rotations 31

Sweet clover as a honey plant 32

GENERAL STATEMENT OF THE USES OF SWEET CLOVER.

The utilization of sweet clover as a feed for all classes of live stock has increased rapidly in many parts of the country, owing primarily to the excellent results obtained by many farmers who have used this plant for pasturage or hay, and also to the fact that feeding and digestion experiments conducted by agricultural experiment stations show that it is practically equal to alfalfa and red clover as a feed.

As a pasture plant, sweet clover is superior to red clover, and possibly alfalfa, as it seldom causes bloat, will grow on poor soils, and is drought resistant. The favorable results obtained from the utilization of this crop for pasturage have done much to promote its culture in many parts of the United States. On account of the succulent, somewhat stemmy growth of the first crop the second year, difficulty is often experienced in curing the hay in humid sections, as it is necessary to cut it at a time when weather conditions are likely to be unfavorable. When properly cured the hay is relished by stock.

At the present time sweet clover is used to only a limited extent for silage, but its use for this purpose should increase rapidly, as the results thus far obtained have been very satisfactory.

In addition to the value of sweet clover as a feed, it is one of the best soil-improving crops adapted to short rotations which can be grown. When cut for hay, the stubble and roots remain in the soil, and when pastured, the uneaten parts of the plants, as well as the manure made while animals are on pasture, are added to the soil and benefit the succeeding crops. In addition to humus, sweet clover, in common with all legumes, adds nitrogen to the soil. This crop is grown in many sections of the country primarily to improve soils, and the benefits derived from it when handled in this manner have justified its use, as the yields of succeeding crops usually are increased materially.

The different species of sweet clover are excellent honey plants, as they produce nectar over a long period in all sections of the United States.

SWEET CLOVER AS A PASTURE CROP.

With the possible exception of alfalfa on fertile soils, no other leguminous crop will furnish as much nutritious pasturage from early spring until late fall as sweet clover when it is properly handled. Live stock which have never been fed sweet clover may refuse to eat it at first, but this distaste is easily overcome by turning them on the pasture in the spring, as soon as the plants start growth (fig. 1). Many cases are on record where stock have preferred sweet clover to other forage plants. The fact that it may be pastured earlier in the spring than many forage plants and that it thrives throughout the hot summer months makes it a valuable addition to the pastures on many farms. Sweet clover is an especially valuable forage plant for poor soils where other crops make but little growth, and it is upon such soils that thousands of acres of this crop are furnishing annually abundant pasturage for all kinds of live stock. In many portions of the Middle West, where the conditions are similar to those of southeastern Kansas, it bids fair to solve the serious pasturage problems. Native pastures which will no longer provide more than a scant living for a mature steer on 4 or 5 acres, when properly seeded to sweet clover will produce sufficient forage to carry at least one animal to the acre throughout the season. In addition to this, a crop of hay or a seed crop may be harvested from a portion of the land when it is so fenced that the stock may be confined to certain parts of the field at specific times. Land which is too rough or too depleted for cultivation, or permanent pastures which have become thin and weedy, may be improved greatly by drilling in, after disking, a few pounds of sweet-clover seed per acre. Not only will the sweet clover add considerably to the quality and quantity of the pasturage but the growth of the grasses will be improved by the addition of large quantities of humus and nitrogen to the soil.

Sweet clover has proved to be an excellent pasture crop on many of the best farms in the North-Central States. In this part of the country it may be seeded alone and pastured from the middle or latter part of June until frost, or it may be sown with grain and pastured after harvest.

When sweet clover has been seeded two years in succession on separate fields, the field sown the first year may be pastured until the middle of June, when the stock should be turned on the spring seeding. When handled in this manner excellent pasturage is provided throughout the summer, and a hay or seed crop may be harvested from the field seeded the previous season.

Some of the best pastures in Iowa consist of a mixture of Kentucky bluegrass, timothy, and sweet clover. On a farm observed near Delmar, Iowa, stock is pastured on meadows containing this mixture from the first part of April to the middle of June. From this time until the first part of September the stock is kept on one-half to two-thirds the total pasture acreage. The remainder of the pasture land is permitted to mature a seed crop. After the seed crop is harvested the stock again is turned on this acreage, where they feed on the grasses and first-year sweet-clover plants until cold weather. The seed which shatters when the crop is cut is usually sufficient to reseed the pastures. By handling his pasture land in this manner, the owner of the farm has always had an abundance of pasture and at the same time has obtained each year a crop of 2 to 4 bushels of recleaned seed to the acre from one-third to one-half of his pasture land. This system has been in operation on one field for 20 years and not until the last two year's has bluegrass showed a tendency to crowd out the sweet clover. It is essential that sufficient stock be kept on the pastures to keep the plants eaten rather closely, so that at all times there will be an abundance of fresh shoots.

Whenever the first crop of the second year is not needed for hay or silage it can be used for no better purpose than pasturage. In fact, it is better to pasture the fields until the middle of June, as this affords one of the most economical and profitable ways of handling the first crop. In addition to its value for pasture, grazing induces the plants to send out many young shoots close to the ground, so that when the plants are permitted to mature seed a much larger number of stalks are formed than would be the case if the first crop were cut for hay. The hay crop is likely to be cut so close to the ground that the plants will be killed, whereas but little danger of killing the plants arises from close pasturing early in the season. Excellent stands of sweet clover will produce an abundance of pasturage for two to three mature steers per acre from early spring to the middle of June.

Cattle which are pasturing on sweet clover alone crave dry feed. Straw has been found to satisfy this desire and straw or hay should be present in the meadow at all times, After stock are removed from the field it is an excellent plan to go over it with a mower, setting the cutter bar so as to leave the stubble 6 to 8 inches high. This will even up the stand, so that the plants will ripen seed at approximately the same date.

Experiments by many farmers in the Middle West show that sweet clover is an excellent pasture for dairy cattle. When cows are turned on sweet clover from grass pastures the flow of milk is increased and its quality improved. Other conditions being normal, this increase in milk production will continue throughout the summer, as the plants produce an abundance of green forage during the hot, dry months when grass pastures are unproductive. If pastures are handled properly they will carry at least one milk cow to the acre during the summer months.

In many parts of the country sweet clover has proved to be an excellent pasturage crop for hogs. When it is utilized for this purpose it usually is seeded alone and pastured for two seasons. The hogs may be turned on the field the first year as soon as the plants have made a 6-inch growth. From this time until late fall an abundance of forage is produced, as pasturing induces the plants to send out many tender, succulent branches. Pasturing the second season may begin as soon as growth starts in the spring. If the field is not closely grazed the second season it is advisable to clip it occasionally, leaving an 8-inch stubble, so as to produce a more succulent growth.

An acre of sweet-clover pasture ordinarily will support 20 to 30 shotes in addition to furnishing a tight cutting of hay (fig. 2). For the best growth of the hogs, they should be fed each day 2 pounds of grain per hundredweight of the stock. Hogs are very fond of sweet clover roots and should be ringed before being turned on the pasture. The tendency to root may generally be overcome by adding some protein to the grain ration. Meat meal serves this purpose very well.

The Iowa Agricultural Experiment Station conducted an interesting pasturing experiment with spring pigs in 1910, In this experiment, pigs weighing approximately 38 pounds each were pastured for a period of 141 days on two plats of red clover, a plat of Dwarf Essex rape, and a plat of yellow biennial sweet clover. The pigs pasturing on each plat received a ration of ear corn. The ration given to the pigs on one plat of red clover and on that of rape was supplemented with meat meal to the extent of one-tenth of the ear corn ration. The feed given to the pigs pasturing on sweet clover was supplemented with meat meal at the same rate during only the last 57 days of the test. The red clover was seeded in 1908 and reseeded in 1909, so that the plat contained a very good stand of plants at least one year old. The sweet clover was seeded in the spring of 1910, while the rape was sown on April 4, 1910, in 24-inch rows. The pigs were turned on the forage plats on June 22.

The results of this experiment, as presented in Table I, show that sweet clover carried more pigs to the acre and produced cheaper gains and a greater net profit per acre than either red clover or rape. To judge from the date of seeding of the plants tested, it was to be expected that the pigs pasturing on the sweet clover would not gain as rapidly at first as those pasturing on the other forage plants, as the growth of the sweet clover at this time was undoubtedly much less than that of the other crops. This assumption is borne out by the results given for the first 84 days of the test. During this period the pigs on the rape made a net gain of $11.55 per acre and those on the red clover $6.86 per acre more than those on the sweet clover. In these computations corn was valued at 50 cents per bushel and hogs at $6 per hundredweight. During the latter part of the experiment there was but a scant growth of red clover on the plats, while the sweet clover produced an abundance of forage, and during this period of the experiment the pigs pasturing on sweet clover made a net gain of $10.14 per acre more than those pasturing on red clover and $17.41 per acre more than those pasturing on rape. (Table I.) The difference in net profits probably would have been greater had white sweet clover been used instead of yellow sweet clover, as it makes a larger growth and contains approximately the same ratio of food elements.

Table I.--Relative merits of Dwarf Essex rape, red clover, and yellow sweet clover when pastured by spring pigs for 141 days, June 22 to November 10, 1910.

+------+-------+-------+--------+---------------+--------+------- | | | | |Supplementary | | | | | | |feed required | Total | Net | | | | | for 100 | cost |profit | |Initial| Total |Average |pounds of gain.| of 100 | per |Number| weight| gain, | daily +-------+-------+ pounds |acre.[3] Forage tested, plat area, | of | per | all | gain |Shelled| Meat | of | and ration. | hogs.| hog. | hogs. |per hog.| corn. | Meal. |gain.[2]| ---------------------------+------+-------+-------+--------+-------+-------+--------+-------- | |Pounds.|Pounds.| Pounds.|Pounds.|Pounds.| | Rape (Dwarf Essex, 0.9 | | | | | | | | acre), and ear corn[4] | | | | | | | | plus one-tenth meat meal.| 18 | 37.8 |2,801.7| 1.10 | 292.5 | 33.99 | $3.79 | ...... Reduced to acre basis. | 20 | .... |3,113.0| .... | ..... | ..... | ..... | $88.64 | | | | | | | | Clover (medium red, 0.8 | | | | | | | | acre) and ear corn | | | | | | | | alone[4]. | 15 | 39.0 |1,790.0| .84 | 370.6 | None. | 3.71 | ...... Reduced to acre basis. | 18.75| .... |2,237.5| .... | ..... | ..... | ..... | 51.20 | | | | | | | | Clover (medium red, 0.8 | | | | | | | | acre) and ear corn[4] | | | | | | | | plus one-tenth meat meal.| 15 | 39.0 |2,394.0| 1.13 | 299.3 | 34.77 | 3.84 | ...... Reduced to acre basis. | 18.75| .... |2,992.5| .... | ..... | ..... | ..... | 64.55 | | | | | | | | Sweet clover[5] (yellow | | | | | | | | biennial, 0.8 acre) and | | | | | | | | ear corn[4] plus | | | | | | | | one-tenth meat meal. | 18 | 37.8 |2,594.0| 1.02 | 313.6 | 24.70 | 3.70 | ...... Reduced to acre basis. | 22.60| .... |3,242.5| .... | ..... | ..... | ..... | 74.50 ---------------------------+------+-------+-------+--------+-------+-------+--------+---------

[2] Corn valued at 50 cents per bushel, meat meal at $2.50 per hundredweight.

[3] Hogs valued at $6 per hundredweight.

[4] During the first 84 days of the test, practically two-thirds of the time, a limited ration of corn was given, while during the last 57 days the pigs received a full feed.

[5] The pigs pasturing on sweet clover received meat meal only during the last 57 days of the experiment.

An experiment reported by the New Jersey Agricultural Experiment Station shows that a mixture of rape and sweet clover makes an exceptionally fine pasture for hogs. In this experiment the mixture of rape and sweet clover produced more pasturage than alfalfa and was preferred to alfalfa by the hogs. It was seeded at the rate of 6 pounds of Dwarf Essex rape and 10 pounds of sweet clover to the acre.

Sheep relish sweet clover and make rapid gains when pastured on it. Care must be taken to see that pastures are not overstocked with sheep, as they are likely to eat the plants so close to the ground as to kill them. This is especially true the first year, before the plants have formed crown buds. Yellow biennial sweet clover probably would not suffer from this cause as much as the white species, because the plants make a more prostrate growth and are not likely to be eaten so closely to the ground.

Horses and mules do well on sweet-clover pastures. On account of the high protein content sweet clover provides excellent pasturage for young stock. No cases of slobbering have been noted with horses.

TAINTING MILK AND BUTTER.

Milk may be tainted occasionally when cows are pasturing on sweet clover. However, the large majority of farmers who pasture sweet clover on an extensive scale report very little or no trouble. The flavor imparted to milk at times is not disliked by all people, as some state that it is agreeable and does not harm the market value of dairy products in the least. This trouble is experienced for the most part in the early spring. The tainting of milk may be avoided by taking the cows off the pasture two hours before milking and keeping them off until after milking the following morning.

BLOATING.

Unlike the true clovers and alfalfa, sweet clover seldom causes bloat; in fact, with the exception of the summer of 1915, only a few authentic cases of bloat have thus far been recorded in sections where large acreages are pastured with cattle and sheep. A number of cases of bloat wore reported in Iowa during the abnormally wet season of 1915. No satisfactory explanation for this comparative freedom from bloating has been offered. It is held by some that the coumarin in the plants prevents bloating, but this has not been established experimentally.

TREATMENT FOR BLOAT.

_Cattle._--If the case of bloat is not extreme, it may be sufficient to drive the animals at a walk for a quarter or half an hour. In urgent cases the gas must be allowed to escape without delay, and this is best accomplished by the use of the trocar. In selecting the place for using the trocar, the highest point of the distended flank equally distant from the last rib and the point of the hip must be chosen. Here an incision about three-fourths of an inch long should be made with a knife through the skin, and then the sharp point of the trocar, being directed downward, inward, and slightly forward, is thrust into the paunch. The sheath of the trocar should be left in the paunch as long as any gas continues to issue from it. In the absence of a trocar an incision may be made with a small-bladed knife and a quill used to permit the gas to escape. Care must be taken to see that the quill does not work down out of sight into the incision.

Another remedy consists in tying a large bit, the diameter of a pitchfork handle, in the mouth, so that a piece of rubber tubing may be passed through the mouth to the first stomach to allow the gas to escape.

When the animal is not distressed and the swelling of the flank is not great, or when the most distressing condition has been removed by the use of the trocar, it is best to administer internal medicine. Two ounces of aromatic spirits of ammonia should be given every half hour in a quart of cold water, or half an ounce of chlorid of lime may be dissolved in a pint of tepid water and the dose repeated every half hour until the bloating has subsided.[6]

[6] See "Diseases of Cattle," a special report of the Bureau of Animal Industry.

For acute bloating the Kentucky Agricultural Experiment Station recommends 1 quart of a 1-1/2 per cent solution of formalin, followed by placing a wooden block in the animal's mouth and by gentle exercise if the animal can be gotten up.

_Sheep._--Gas may be removed quickly from bloated sheep by using a small trocar. The seat of the operation is on the most prominent portion of the left flank.

SWEET-CLOVER HAY.