PALATABILITY OF SWEET CLOVER.

The woody growth of sweet clover as it reaches maturity and the bitter taste due to coumarin have been the principal causes for live stock refusing to eat it at first. On this account many farmers have assumed it to be worthless as a feed. It is a fact that stock seldom eat the hard, woody stems of mature plants, but it is true also that stock eat sparingly of the coarse, fibrous growth of such legumes as red or mammoth clover when they have been permitted to mature and have lost much of their palatability. All kinds of stock will eat green sweet clover before it becomes woody, or hay which has been cut at the proper time and well cured, after they have become accustomed to it. Many cases are on record in which cattle have refused alfalfa or red clover when sweet clover was accessible. Milch cows have been known to refuse a ration of alfalfa hay when given to them for the first time. Western range cattle which have never been fed corn very often refuse to eat corn fodder, or even corn, for a short time, and instances have come under observation in which they ate the dried husks and left the corn uneaten. When these cattle were turned on green grass the following spring they browsed on the dead grass of the preceding season's growth, which, presumably more closely resembled the grass to which they were accustomed. Such preliminary observations should never be taken as final, even when they represent the results of careful investigators. When cowpeas were first introduced into certain sections of this country much trouble was experienced in getting stock to eat the vines, either when cured into hay or made into ensilage. This difficulty, however, was soon overcome.

It is very true that stock which have never been pastured on sweet clover or fed on the hay must become accustomed to it before they will eat it, but the fact that sweet clover is now being fed to stock in nearly every State indicates that the distaste for it can be overcome easily and successfully. As sweet clover usually starts growth earlier in the spring than other forage plants and as the early growth presumably contains less coumarin than older plants, stock seldom refuse to eat it at this time. Properly cured hay is seldom refused by stock, especially if it is sprinkled with salt water when the animals are salt hungry.

COMPOSITION OF SWEET CLOVER.

Sweet clover, like most legumes, contains a relatively high percentage of protein, thus making it a source of that valuable constituent of feeds needed for growing stock and for the production of milk. Table IV shows the relative composition and digestibility of sweet clover as compared to some other feeds.

Table IV.—Composition and digestibility of sweet clover compared with that of other forage crops.

AVERAGE PERCENTAGE COMPOSITION OF SWEET CLOVER AND OTHER FORAGE CROPS.

DIGESTIBLE NUTRIENTS OF SWEET CLOVER AND OTHER FORAGE CROPS WHEN FED TO SHEEP.[12]

Table IV shows that the percentage composition of both green and cured sweet clover compares favorably with that of alfalfa and red clover.

Perhaps the most interesting point shown in this table is that the fiber content of white sweet clover, whether green or cured into hay, is no greater than that of alfalfa. It is understood, however, that the plants collected for these analyses were taken when they were at the proper stage for curing into hay. Table IV also shows that the digestible nutrients of sweet clover when fed to sheep compare favorably with alfalfa. It was stated that the sweet-clover hay used for this experiment was stemmy and that it had not been cut until it had become woody. The pea hay had passed the best stage for cutting when it was harvested, while the alfalfa hay was in excellent condition.

In a feeding experiment with sheep conducted by two students at the Iowa State College it was found that the protein digested in sweet-clover feed alone was 69 per cent and that the addition of corn to the hay ration increased the digestibility of sweet clover to 82 per cent. Alfalfa and red clover showed similar increases of the digestibility of the protein content when corn was added to the ration. The percentage of digestibility figured for the protein in the corn was the average of a number of digestion experiments. The probability is that the digestibility of the corn was also increased by the presence of the hay in the ration, so that not all the increase in the digestibility should be credited to the hay constituents of the different rations.

FEEDING EXPERIMENTS WITH SWEET CLOVER.

Few agricultural experiment stations have carried on definite feeding experiments to determine the value of sweet clover compared with other feeds.

The South Dakota Agricultural Experiment Station reported an experiment in which lambs were fed on sweet-clover hay in comparison with alfalfa, pea-vine, and prairie hay. In this experiment the lambs made a better gain at a less cost when fed sweet-clover hay than when fed pea-vine hay, but not as large a gain as when fed alfalfa hay. The results of this experiment are shown in Table V.

Table V.—Feeding experiment with lambs in South Dakota, showing the comparative value of different kinds of hay as roughage.

[Grain ration consists of oats and corn in all cases; roughage varies.]

The Wyoming Agricultural Experiment Station also performed an, interesting experiment with lambs. A number of pens of 10 to 40 lambs each were fed different mixtures of feeds for 14 weeks. Those receiving sweet-clover hay, corn, and a small amount of oil meal made an average gain of 30.7 pounds per head, as compared with 20.3 pounds for those receiving native-grass hay, oats, and oil meal. Those receiving alfalfa hay and corn made a gain of more than 34 pounds per head. The results obtained with four pens of lambs in this experiment are given in Table VI.

Table VI.—Results of feeding tests of lambs in Wyoming covering 14 weeks.

The sweet-clover hay used in this experiment was described as stemmy and more than a year old; yet it was eaten up clean by the lambs.

The South Dakota Agricultural Experiment Station conducted an experiment in which steers were fed corn silage and various kinds of hay, including sweet clover. The steers which were fed corn silage and sweet-clover hay made an average daily gain of 2.45 pounds, at a cost of $4.34 per hundred pounds of gain, whereas the steers which were fed corn silage and red-clover hay made an average daily gain of 2.29 pounds, at a cost of $4.55 per hundred. The steers that were fed corn silage and alfalfa hay made an average daily gain of 2.49 pounds, at a cost of $4.30 per hundred. In computing the cost of the gains, corn silage was valued at $3 per ton, alfalfa, red-clover, and sweet-clover hay at $10 per ton, and prairie hay at $6 per ton. The results of this experiment, as given in Table VII, show that sweet-clover hay is practically equal to red-clover and alfalfa and greatly superior to prairie hay for roughage for steers.

Table VII.—Feeding experiments with steers in South Dakota, showing the value of sweet-clover hay as compared with some other kinds of hay.

[Corn silage fed in all cases; kind of hay varies.]

The results of these various experiments are being duplicated every year by many feeders. Each year in the Middle West and Northwest many cattle that bring high prices are being fed with no other roughage than sweet-clover hay. Steers which have been pastured entirely on sweet clover have brought in the Chicago market $1 per hundredweight more than ordinary grass-pastured stock marketed from the same locality and at the same time.

Excellent results were obtained in Lee County, Ill., from feeding steers sweet-clover silage made from plants which had matured a seed crop. For this experiment 91 head of steers 2 and 3 years old, averaging 1,008 pounds per head, were purchased at the Kansas City stock yards on November 16, 1915, at a cost of $6.30 per hundred. These steers were shipped to a farm at Steward and immediately turned on 120 acres of cornstalks. They were fed nothing in addition to the cornstalks until January 14, 1916, when they were put into the feed lot. While they were not weighed when turned into the feed lot, the owner of the steers stated that in his estimation they had gained but little, if any. During the 60 days these steers were in the feed lot they were fed 25 bushels of snapped corn twice a day and as much sweet-clover silage as they would eat. These animals had access to sweet-clover straw during the first part of the feeding period, but after this was consumed they had only oat straw as roughage. At the end of the feeding period they were sold on the Chicago market at the average price of $8.25 per hundred, netting approximately $30 per head. The average weight of these steers in the Chicago yards was 1,177 pounds, 169 pounds more than when purchased in Kansas City.

A most remarkable feature of this experiment is the fact that the steers were fed almost entirely material which would have been considered of little value by the average farmer. The corn which was fed tested 44 per cent moisture at the Rochelle, Ill., elevator, and 20 cents per bushel was the best price offered for it.

Presumably on account of wet weather during the fall of 1915, the sweet-clover seed crop was a failure in that section; in fact, the crop had been cut for seed and part had been thrashed before it was decided that the seed yield was not sufficient to pay for the thrashing. The remainder of the crop was then run into the silo and fed to the steers. The leaves fall and the stems of this plant become hard and woody as the seed matures. The crop therefore would have been worthless for feed had it not been placed in the silo. As a rule, stock readily eat sweet-clover straw when the stems are broken and crushed by the hulling machines. The sweet-clover straw which was used as roughage during the first part of the feeding period was from that part of the seed crop which had been thrashed.

An interesting feeding experiment was conducted on a farm at Rochelle, Ill. On September 7, 1913, 29 head of 2-year-old steers, averaging 836 pounds, were turned on 40 acres of sweet clover which had been seeded that spring with barley. These animals were pastured on the sweet clover until November 1 without additional feed. During this time they made exceptionally large gains. From November 1 to December 11, 28 head of these steers had access to an 80-acre field of cornstalks. On December 11 they were put into the feed lot. During the time these steers were on the cornstalks they barely held their gain, but during the first 30 days they were in the feed lot they made an average daily gain of almost 3 pounds. In this period they received 215 bushels of corn-and-cob meal and 16³/₄ tons of silage made from the first-year growth of sweet clover. During the next 30 days they received 388 bushels of corn-and-cob meal and much less sweet-clover, silage. During this time they made an average daily gain of 2 pounds. When the corn-and-cob meal ration was increased the steers ate less silage. These cattle dressed 55¹/₈ per cent at a Chicago packing house.