Abstract
To promote desired forest conditions that enhance wildlife habitat in bottomland forests, managers prescribed and implemented variable-retention harvest, a.k.a. wildlife forestry, in four stands on Tensas River National Wildlife Refuge, LA. These treatments created canopy openings (gaps) within which managers sought to regenerate shade-intolerant trees. Six years after prescribed harvests, we assessed regeneration in 41 canopy gaps and 4 large (>0.5-ha) patch cut openings that resulted from treatments and in 21 natural canopy gaps on 2 unharvested control stands. Mean gap area of anthropogenic gaps (582 m²) was greater than that of natural gaps (262 m²). Sweetgum (
Liquidambar styraciflua) and red oaks (
Quercus nigra, Q. nuttallii, and
Q. phellos) were common in anthropogenic gaps, whereas elms (
Ulmus spp.) and sugarberry (
Celtis laevigata) were numerous in natural gaps. We recommend harvest prescriptions include gaps with diameter >25 m, because the proportion of shade-intolerant regeneration increased with gap area up to 500 m². The proportion of shade-intolerant definitive gap fillers (individuals likely to occupy the canopy) increased with gap area: 35 percent in natural gaps, 54 percent in anthropogenic gaps, and 84 percent in patch cuts. Sweetgum, green ash (
Fraxinus pennsylvanica), and red oaks were common definitive gap fillers.
Parent Publication
Citation
Twedt, Daniel J.; Somershoe, Scott G. 2013. Regeneration in bottomland forest canopy gaps 6 years after variable retention harvests to enhance wildlife habitat. In: Guldin, James M., ed. 2013. Proceedings of the 15th biennial southern silvicultural research conference. e-Gen. Tech. Rep. SRS-GTR-175. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. 261-269.