Effects of Grazing Management on Establishment and Productivity of Aeschynomene Overseeded in Limpograss Pastures¹

Abstract

Low protein concentration in limpograss [Hemarthria altissima (Poir.) Stapf et C.E. Hubb.] herbage is thought to limit the performance of grazing animals. In 1983 and 1984 an experiment was conducted on a sandy, siliceous, hyperthermic Ultic Haplaquod soil to evaluate effects of grazing management on establishment and productivity of the legume aeschynomene (Aeschynomene americana L.) seeded in limpograss. Existing limpograss pastures were grazed in the spring to 75‐ or 150‐mm stubble heights. After broadcast seeding aeschynomene, stubble heights were maintained by grazing until (i) legume cotyledons were exserted, (ii) two true leaves were present, or (iii) 2 weeks after the two‐leaf stage. Summer grazing was initiated when aeschynomene plants were 0.20, 0.40, or 0.80 m tall in 1983 and 0.20, 0.40, or 0.60 m tall in 1984. After initiation of grazing, pastures were grazed every 5 weeks. Limpograss stubble height during legume establishment did not affect legume productivity, but there was a trend favoring the 75‐mm level. Extending the period of early season grazing of limpograss until aeschynomene seedlings reached at least the two‐leaf stage controlled grass competition and maximized legume performance. Legume dry matter (DM) accumulation was greatest if initiation of summer grazing was delayed until aeschynomene was 0.80 (1983) or 0.60 (1984) m tall. Initiation of grazing when aeschynomene was 0.20 to 0.40 m tall resulted in more uniform distribution of total and legume DM, higher efficiency of grazing, more vigorous legume regrowth, and a trend toward greater total herbage consumption. These data indicate that aeschynomene can be established into limpograss sods under grazing, and that this association has potential on the large expanses of poorly drained soils in Florida.

Plant Responses to Stocking Rate in a Subtropical Grass‐Legume Pasture

“…Stocking rate did not affect (P > 0.10) bahiagrass percentage, although means of 87.6, 82.0, and 84.4% bahiagrass at the high, intermedliate, and low stocking rates, respectively, were inversely related to carpon desmodium percentage. Percentage of aeschynomene plus phasey bean was not affi~cted (P > 0.1 0) by stocking rate, even though the results of Mislevy et al ( 1981) and Sollenberger et al (1987a) indicate that aeschynomene production can be affi~cted by defoliation management.…”

Sustainable, low‐input, warm‐season, grass–legume grassland mixtures: mission (nearly) impossible?

“…If a perfect match is not possible, then grazing strategies that force animals to graze all species somewhat similarly before moving on can sometimes equalize the effects of grazing defoliation. This can be achieved through such approaches as rotational grazing, successive waves of selective versus bulk grazers or hay harvest following short‐duration grazing (Sollenberger et al. , 1987a,b).…”

“…In the area between the temperate and tropical climatic regions, however, persistent combinations of pasture grasses and legumes are rare and monocultures are common. Exceptions include some subtropical locations where sustained research efforts have provided useful species combinations such as those developed for south‐east Queensland, Australia (Schulke, 2000; Jones and Bunch, 2003) and peninsular Florida (Sollenberger et al. , 1987b; Aiken et al.…”

Limpograss Sod Management and Aeschynomene Seed Reserve Effects on Legume Reestablishment

“…Although greater animal performance has resulted from planting aeschynomene with limpograss (Rusland et al, 1988), long-term stand survival of aeschynomene will require careful management of initial establishment (Kalmbacher et al, 1988;Sollenberger et al, 1987), of grazing during the autumn flowering and seed-setting period (Chaparro et al, 1991), and of reestablishment in spring and early summer (current study). Reestablishment is made more difficult because occurrence of adequate rainfall during spring and early summer in the Gulf-coast region is not reliable.…”

“…Initial establishment of aeschynomene into bahiagrass (Paspalum notatum Flugge) sod using scarified seed has been enhanced by controlling grass competition with herbicides, burning, or grazing (Kalmbacher and Martin, 1983). In limpograss sods, maintaining an 8-cm grass stubble by grazing until aeschynomene seedlings were 5 em tall resulted in successful initial legume establishment (Sollenberger et al, 1987). Use of tillage operations such as disking to control grass competition has had mixed results.…”