The reduction of forest floor ground cover and litter layers by prescribed fires may alter the morphology (field and micro) and physical properties of surface horizons. This study determined long‐term (35 yr) changes in surface horizon bulk density, organic matter concentration and content, and morphology in response to periodic (5 yr) and annual (1 yr) prescribed fires. Soils were fine‐silty, siliceous, thermic Glossic Fragiuldults, supporting mixed oak vegetation in middle Tennessee. Upper mineral soils (0‐ to 2‐cm and 0‐ to 7.6‐cm depths) were sampled and detailed field descriptions made. Periodic and control plots had a thin layer of Oi, Oe, and Oa horizons 5 yr after the 1993 burn, whereas on annual burn plots a 1‐ to 2‐cm charred layer was present. Significant reductions in organic matter concentration and mean thickness of the A horizon were found from burning (A horizons thicknesses were 6.4, 4.6, and 2.9 cm in control, periodic, and annual plots, respectively). Periodic burns did not significantly alter the organic matter and bulk density of the upper 7.6 cm of mineral soil; however, annual burns did result in significantly higher bulk densities (1.01, 1.07, and 1.29 Mg m−3 in control, periodic, and annual plots, respectively) and lower organic matter concentrations and contents. Microscopic investigations confirmed that compaction was increased from annual burning. Thin sections also revealed that the granular structure of the A horizons in control and periodic plots resulted from bioterbation of macro and mesofauna, fungi, and roots. Long‐term annual burning greatly affected surface soil properties, whereas periodic burning on a 5‐yr cycle had only limited effects.
Color aerial photography was used to assess crown color classes in loblolly pine (Pinus taeda L.) plantations. Three distinct Munsell color classes were delineated on the resulting photographs. Foliar N levels and, to a lesser degree, foliar K levels were directly related to color. Significant relationships between color and site index and color and basal area were shown. Application of color aerial photography, combined with Munsell color coding, could expedite land classification and also make possible more efficient use of fertilizers. South J. Appl. For. 12(4):270-273.
Performance of 1-0 bareroot green ash (Fraxinus pennsylvanica Marsh.), sycamore (Platanus occidentalis L), and baldcypress (Taxodium distichum L., Rich.) planted on drained beaver (Castor canadensis) impoundments in southwest Tennessee was promising at the end of three growing season.First-year survival was significantly increased in plots where swamp cut grass (Leersia oryzoides) was controlled; however, effective grass control opened the site to aggressive invasion by broadleaf herbaceous vegetation. No treatment effect was noted for survival or growth of seedlings by the end of the third year. Containerized seedlings of swamp white oak (Quercus michauxii Nutt.) and willow oak (Quercus phellos L) failed due to poorly developed planting stock. Natural regeneration 3 years after drainage was poor, averaging 333 boxelder (Acer negundo L.), 42 black willow(Salix nigra Marsh), and 21 cherrybark oak (Quercus falcata var. pagodaefolia Ell.) stems/ac. Continued beaver control was necessary to prevent recolonization of plantation sites. South. J. Appl. For. 16(3):151-155.
Relationships between forest communities and landtypes (the most detailed level of a hierarchical land classification system) were determined for the Prentice Cooper State Forest (PCSF), located on the southern tip of Walden Ridge, west of Chattanooga, Tennessee.Four extensive landtypes within the Mullins Cove area of PCSF were sampled: 1) broad sandstone ridges-south aspect (LT-3), 2) north sandstone slopes (LT-5), 3) south sandstone slopes (LT-6), and 4) plateau escarpment and upper sandstone slopes and benches-south aspect (LT-17). Rectangular, 0.04-hectare plots specified sub-plots for sampling overstory, midstory, sapling/shrub, seedling/herb forest strata, and physical site characteristics. Plots (139) were allocated by landtype using a random start with subsequent systematic location.Multivariate statistical techniques were used to 1) examine the distinctness of forest communities occurring among landtypes (discriminant analysis), 2) describe the forest communities occurring within landtypes (cluster analysis), and 3) determine factors controlling the spatial distribution of forest communities on the landscape (factor analysis).Different relative importance values of species among communities along with different community combinations among landtypes resulted in distinct forest vegetation among landtypes.Chestnut oak (Quercus prinus L.), white oak (Quercus alba L.), and shortleaf pine (Pinus echinata Miller) communities occurred on all four landtypes. Scarlet oak (Quercus coccinia Muenchh.) communities occurred on LT-5, LT-6, and LT-17. Black oak (Quercus velutina Lam.) communities occurred on LT-3 and LT-5. Yellow-poplar (Liriodendron tulipifera L.), northern red oak (Quercus rubra L.), and eastern hemlock (Tsuga canadensis (L.) Carr.), communities occurred only on LT-17.Landscape scale factors that varied along an elevation gradient were dominant in controlling spatial distribution of forest communities. Microsite factors were secondary controllers. Specific ecological factors could not be determined by factor analysis.Relatively distinct vegetation occurs among sampled landtypes on the PCSF. This study provides additional evidence that the land classification system divides the Mid-Cumberland Plateau landscape into distinct ecological units.
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