It is often stated that the first crop of sweet clover will produce more seed to the acre than the second crop. This depends very largely upon the thickness of the stand and on weather conditions. In regions where two crops may be grown in a season, the first usually will produce more seed to the acre than the second if the field has a thin stand. When the stand is thick the second crop ordinarily yields more seed. In regions where a crop of hay or pasturage may be obtained in addition to the seed crop, it is seldom an economical procedure to permit the first crop to mature. Not only will sweet clover produce an abundance of nutritious pasturage or a cutting of 1 to 3 tons of hay in addition to the seed, but the difficulty of handling the large, stemmy growth of the first crop for seed is avoided.
Yields of sweet-clover seed have been reduced during the last two seasons by several fungous diseases. Experimental work has not been completed to show the percentage of damage done by these organisms, but in some sections of the country seed yields were reduced considerably. The clover stem borer,[2] which is prevalent in red clover in certain sections of the country, also infests sweet clover. It is probable that this insect did some damage to the seed crop in certain sections of the country in 1916.
[2] Languria mozardi.
The yield of sweet-clover seed varies from 2 to 10 bushels of re-cleaned seed per acre.
[SWEET-CLOVER STRAW.]
Sweet-clover straw may be utilized for soil improvement or as a roughage for stock. When it is not needed for feeding it should be turned under, as it will add much humus and nitrogen to the soil. When the seed is flailed from the plants the straw may be easily and quickly spread over the land at the time of flailing, but when the crop is thrashed with a grain separator or a clover huller it will be necessary to haul the straw and scatter it over the field. When the crop is thrashed in this manner the straw will be broken and crushed so that stock will eat it freely. The straw may be run directly from the thrashing machine into the silo, where, by adding sufficient water, it can be made into good silage. [Table I] gives the analyses of nine samples of sweet-clover straw which were collected in Illinois in the fall of 1916.
Table I.—Analyses of sweet-clover straw.[3]
| Sample. | Moisture. | Ash. | Fiber extract. | Protein. | Crude fiber. | Nitrogen-free extract. |
| No. 1 | 4.2 | 3.18 | 1.20 | 8.31 | 49.37 | 33.74 |
| No. 2 | 4.7 | 3.40 | 1.03 | 5.88 | 53.65 | 31.34 |
| No. 3 | 5.34 | 3.02 | .89 | 6.14 | 51.11 | 32.9 |
| No. 4 | 5.55 | 4.14 | 1.54 | 8.44 | 43.00 | 37.33 |
| No. 5 | 4.75 | 2.64 | 1.28 | 6.81 | 51.42 | 32.8 |
| No. 6 | 4.23 | 2.58 | 1.13 | 5.44 | 55.41 | 31.21 |
| No. 7 | 5.53 | 3.66 | 1.52 | 7.19 | 46.34 | 35.70 |
| No. 8 | 4.65 | 2.98 | 1.38 | 7.09 | 51.56 | 32.34 |
| No. 9 | 4.92 | 4.22 | 1.70 | 8.44 | 46.11 | 34.61 |