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.
Fig. 2.—Hogs pasturing on sweet clover.
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.
| Forage tested, plat area, and ration. | Number of hogs. | Initial weight per hog. | Total gain, all hogs. | Average daily gain per hog. | Supplementary feed required for 100 pounds of gain. | Total cost of 100 pounds of gain.[2] | Net profit per acre.[3] | |
| Shelled corn. | Meat meal. | |||||||
| 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.