No abstract

We studied dietary overlap between captive white-tailed deer (n = 3) (Odocotleus tir@nlanus) and cattle (n = 4) for 3 years on 2 rotationally burned, 54-ha longleaf pine (Pinus paZustris)-bluestem (Andropogon spp.) pastures in central Louisiana. A third of each pasture was burned each year in late February. One pasture was grazed heavily (61-77% herbage use) yearlong; the other was grazed heavily (SO-67% use) from mid-April to 1 November. Deer diets were dominated yearlong by a mixture of browse (49.3~83.2%) and forbs (11.2-47.1%). Cattle consumed mostly grasses during spring and summer and 60 and 40% browse and herbage, during fall and winter, respectively. Cattle consumed more herbage on first-year burns. Dietary overlap under heavy yearlong grazing averaged 25.8, 11.8, 26.0, and 30.7% during spring, summer, fall, and winter, respectively. Overlap under heavy seasonal grazing averaged 18.5, 7.4, and 22.6% during spring, summer, and fall, respectively. Diets of both animals were diverse and overlap generally resulted from sharing small amounts of many plant taxa. Except on recent burns during summer, dietary overlap under heavy yearlong grazing was comparable to that observed under moderate yearlong grazing at half the cattle stocking rate. Moderate grazing (40-50% herbage removal) of similar range from late spring through early fall should have little negative impact on deer forage availability. Grazing during late fall and winter reduces an already limited supply of deer forage by reducing availability of evergreen browse and herbaceous winter rosettes. J. WILDL. MANAGE. 53(3):540-548 1 1 1 p Within wmdy and nonwoody categories, taxa with highest seasonal totals across both grazing treatments are ranked first. b SP = 31 Mar-6 Jun, SU = 23 Jun-13 Aug. FA = 22 Sep-21 Nov, WI = 5 Jan-4 Mar. No winter data for seasonal grazing treatment. ' c Panicum grasses that produce basal rosettes during winter. 4 Bearded skeletongrass (C. ambfguup) and slim skeletongrass (C. bnwf~ol~us).

This study described the effects of soils, site preparation, and initial pine regeneration spacings on tree growth and the associated understory woody and herbaceous plant succession. Although Sawyer soils appeared more productive than Ruston soils before the harvest and regeneration treatments, woody and herbaceous plant differences were not apparent between the soils after regeneration. During the first 3 years after treatment, the mechanical site preparation method (shear-windrow-burn) reduced woody plant heights more than the underplant-release method; however, these height differences disappeared by the 6th year of post-treatment. Woody plant densities decreased initially, increased by the 6th year after treatment, and decreased to pretreatment levels by the 10th year. Herbage yields increased significantly after site preparation and pine regeneration through the 3rd year, decreased by the 6th year, and declined to levels below pretreatment by the 10th year. Initial pine planting densities did not significantly influence the understory herbage yields during the first 10 years as a result of the confounding effects of the other woody plant growth.

Herbage and browse production after selectively cutting unevenaged stands of loblolly-shortleaf pine to various densities were generally related to residual pine basal area and site quality. Exceptions were at least partially the result of shrub and hardwood crown cover development on the triennially burned range. Uniolas were the principal forage species under stands having high residual pine basal area, bluestems were the major forage component on clearings. Browse made up about one-fourth of the forage under stands having high residual pine basal area but represented considerably lower proportions on clearings. Loblolly pine (Pinus taeda) and shortleaf pine (P. echinata) are the dominant trees in the most extensive forest type in the South. Although timber production is the principal use of these forests, they also provide valuable habitat for white-tailed deer (Odocoileus virginianus) and are grazed extensively by cattle. Management techniques for maintaining or improving the forage resource need refinement, however. This paper reports a study to determine the relation of quantity and composition of understory vegetation to a wide range of overstory densities. The study, begun in 1969, was carried out in uneven-aged stands subjected to a 3-year rotational winter burn. Study Area Three forest blocks at elevations between 42.6 and 48.8 m above sea level in north-central Louisiana were studied. Blocks were 1.6 to 2.2 km apart, and topography within blocks was nearly level. Before cutting treatment, loblolly-shortleaf pine basal area averaged 25.79 m*/ ha. Pines ranged in size up to 71.12 cm dbh. Pine 2.54 cm dbh or larger averaged 278/ha, and pine seedlings were abundant. Loblolly was the dominant pine, having an average site index of 29.88 m at age 50, and a site index range of from 25.50 to 33.54 m. Shortleaf pine site index averaged 26.22 m. The average age of pines was about 50 to 60 years. Differences in tree site quality and corresponding differences in soil series and A-horizon depth were apparent on the study area. Site indices less than 27.50 m included soil series Susquehanna and Keithville, with less than 15.24 cm A-horizon depths; indices more than 29.00 m included series Susquehanna,

Prescribed burning is necessary to restore the herbaceous plant community normally associated with the fire-dependent longleaf pine, Pinus palustris Mill., ecosystem. Usually these burns are done in the winter months. However, burning during the early growing season may allow herbaceous plants to recover better than when burning is conducted during the winter months. It was hoped that the additional herbaceous growth would decrease soil movement, a problem on highly erodible hilltop glades of Kisatchie soil (Typic Hapludalfs). The effects of a May burn on soil movement and vegetation growing on two hilltop glades were monitored through one growing season. A prescribed burn on May 24,1994, reduced vegetation and litter cover on the soil surface and the number of woody plants in the understory. This treatment also adversely affected the richness of woody plants within the herbaceous layer and initially reduced the herbaceous standing crop compared to preburn conditions. Soil movement doubled after the May burn; but in another study, a November burn had a similar effect on soil losses. Because the May burn adversely affected woody plants while maintaining the herbaceous plant community, this treatment may be preferable to winter burning on steep, highly erodible Kisatchie soils.