Abstrakt: |
The establishment and production of short‐lived perennial legumes like ‘American’ jointvetch (Aeschynomene americanaL.) has been more satisfactory than that of perennials in Florida. Since jointvetch can develop into a poorly digestible forage which is rejected by animals, a harvest frequency and cutting height study was conducted on a sandy, siliceous, Typic Haplaquod (Ona fine sand). Jointvetch was cut when plants reached initial heights of 30, 60, and 90 cm, and the plants were cut to leave 8 and 18‐cm stubble heights. Regrowth was cut when plants reached 30, 60, or 90 cm. The plant height at initial harvest was most important in determining the total seasonal yield. Plants cut at 30 cm initially had 60 cm regrowth with 200% more tillers than the initial, but plants cut initially at 60 or 90 cm resulted in regrowth with fewer tillers than the initial harvest. Cutting the initial harvest when plants were 30 cm tall followed by cutting regrowth at 90 cm or cutting the initial and continually recutting at 30 cm resulted in highest dry matter yield and quality. Both crude protein and in vitro organic matter digestion (IVOMD) decreased with increasing regrowth height and more importantly, increasing initial harvest height. Protein and IVOMD of plants cut at an 8‐cm stubble averaged 15.5 and 59.2%, respectively. However, protein (17.4%) and IVOMD (63.1%) were much higher when plants were cut at an 18‐cm stubble. These data indicated that the largest yield and highest quality may be obtained by cutting or grazing jointvetch at the shortest practical initial height (60‐cm initial; 8‐cm stubble). This will allow for multiple harvests of quality forage. |