Over one million hectares of pocosins and wet flats in the southeastern coastal plain are intensively managed for the production of loblolly pine (Pinus taeda) plantations. These management activities may have adverse effects on soil physical properties, site hydrology, and overall site productivity. Substantial quantities of wood residues are often left on these sites by timber harvesting operations, and it was hypothesized that the incorporation of this slash into the soil could improve the soil physical properties and site hydrology. One organic pocosin site and one mineral wet flat site were chosen post-harvest for treatment. The wet flat study was organized as an incomplete block design having four blocks and six treatments: (i) conventional bedding, (ii) strip surface mulching with bedding, (iii) strip surface mulching with tillage and bedding, (iv) broadcast mulch without bedding, (v) broadcast mulch with bedding, and (vi) flat planted control. The pocosin study was organized as a randomized complete block design with four blocks and four treatments. The treatments are identical to those of the wet flat site without the broadcast mulch treatments (iv and v). Soil physical property data was analyzed pre- and post-treatment, while post-treatment site hydrology and soil water chemistry data was analyzed periodically for one year. Seedling survival and height data were analyzed after one growing season. The treatments had little effect on soil physical properties, site hydrology, soil water nutrients, or seedling survival on the wet flat study site. Bedding in general significantly increased tree height growth, but mulching had no significant effects. The treatments had little effect on soil physical properties on the pocosin study site except for soil macroporosity, which was significantly increased by bedding. Site hydrology and soil water nutrients were not significantly affected by the treatments, but seedling survival and height growth were significantly increased by bedding. Mulching had no significant effects on any of the parameters studied. / Master of Science

Site preparation is fundamental for establishing loblolly pine (Pinus taeda L.) plantations, but long-term sustainability of plantations established using mechanical treatments is in question because of concerns regarding soil tillage and the removal of harvest residue and soil organic matter. A study was installed in 1981 on 12 locations in northeastern Georgia and west-central South Carolina to evaluate pine plantation response to mechanical site preparation. Site preparation treatments induced gradients of organic matter manipulation and soil tillage. The treatments included: Control, Chop/Burn, Shear/Disc, Shear/V-Blade, Shear/Rake, and Shear/Rake/Pile. Research was conducted to address the following objectives: (i) compare rotation-age forest response to several intensive site preparation treatments used to establish pine plantations in the Piedmont of the southeastern United States; (ii) correlate growth response with the gradients of soil organic matter removal, soil tillage, and hardwood control; (iii) determine the influence of intensive management on the amount of carbon contained in pine plantations. All site preparation treatments increased year-18 volume accumulation compared to the control treatment. Chop/Burn and Shear/Disc treatments, with pine volumes of 214 m3 ha-1 and 232 m3 ha-1, respectively, conserved harvest residue and out-performed the Shear/Rake treatment (191 m3 ha-1), which completely removed harvest residue. Treatments that included tillage provided growth benefits that lasted throughout the rotation even when tillage was accompanied by complete organic matter removal. Hardwood competition had the greatest influence on pine volume accumulation, explaining over 54% of the variation in pine growth at age 18. Treatments that included tillage most effectively controlled hardwood competition. At year 18, site preparation treatments significantly affected soil organic matter (SOM) content; however, soil nitrogen, foliar nitrogen, bulk density, and macroporosity were not affected by site preparation. All treatments were equally deficient in foliar nitrogen. The Shear/Disc and Shear/Rake/Disc treatments had a significantly positive relationship between foliar nitrogen and pine volume. These treatments had lower hardwood basal areas (below 15%), indicating that once hardwoods were controlled, nitrogen became limiting to pine growth. Using pre-harvest characterization data, carbon accumulation during old-field succession increased fourfold compared to agricultural sites on the nearby Calhoun Experimental Forest. Carbon accumulation on these old-field loblolly pine sites reached quasi-equilibrium after 40 years as shown by uncut reference stands. Site preparation significantly affected the amount of soil C in the upper 20 cm of the soil. Those site preparation treatments that removed harvest residue and accelerated SOM decomposition through tillage had the lowest soil carbon levels. The Shear/Rake/Disc treatment had 10% lower soil carbon content than the Control and Shear/V-Blade treatments. / Master of Science

Chemical site preparation is used to enhance the productivity of loblolly pine plantations; however, it is most often combined with other methods and/or chemical release, and has been studied little on its own. Our study, conducted in the Virginia piedmont, compares the effects of various site preparation applications of imazapyr and their timings (July 23rd, September 3rd, and October 1st 2005) against a year-two chemical release (September 12th 2007), and an untreated check, all following a site preparation burn (June 15, 2005). Testing for additive effects, site preparation treatments were conducted with and without, sulfometuron methyl (SMAX) which targets herbaceous vegetation. Half of all treatments, including the check and release, received a year-one weed control treatment (H) of imazapyr and SMAX. Pines were measured every few years, including the latest measurement in year 14 (2019). Competing hardwood vegetation basal area was measured in year 14. All site preparation treatments reduced competition levels compared to the check, and an inverse relationship exists between competition level and pine volume. Adding SMAX resulted in less effective competition control, but had little effect on pine volumes. Adding H decreased average competition levels, and increased pine volumes. H treatments had the most effect at improving early season (July) applications. September and October treatments generally had more effect than July and the year-two release at controlling competing vegetation, and also showed higher individual pine tree volumes than all other treatments. Chemical site preparation treatments, even performed alone, appear to be valid means of improving pine stands. / Master of Science / Competing vegetation has a negative effect on planted pine production. Areas are often prepared with herbicides or mechanical removal of vegetation before crop-trees are planted (site preparation), or receive herbicide treatments after planting (release), to reduce levels of competition. Our study focuses on pre-planting herbicide (imazapyr with and without sulfometuron methyl) use at different timings (July 23rd, September 3rd, and October 1st). A chemical that targets herbaceous vegetation (sulfometuron methyl) was included in half of the pre-planting treatments, and half of all treatments, including the otherwise untreated check and year-two release, received an added weed control treatment in year-one. This was done to test for potential additive effects of chemical vegetation control options on pine productivity. September and October treatments have a greater effect at controlling competition 14 years since treatment and increasing pine volumes than the July, year-two release, and check. The added herbaceous control increased competition levels on average, without having an effect on the planted pine volumes. The year-one weed control decreased competition levels, and increased pine productivity, particularly within the July treatments. Overall, preparing sites with herbicide is beneficial to the pine stand, even when performed alone. Adding the herbaceous vegetation control is likely not necessary, and the extra year-one weed control may provide a boost to herbicide treatments applied earlier in the season.

Survival and growth of planted trees are common indices used to evaluate success of wetland restoration efforts used to compensate for wetland losses. Restoration efforts on marginal agricultural lands typically result in less than satisfactory survival and growth of desired tree species. This study evaluated seed source ecotype, greenhouse preconditioning and combinations of five mechanical site preparation techniques (mound, bed, rip, disk, pit), four levels of planting stock (gallon, tubeling, bare root, and direct seed), and three planting aids (mat, tube, none) on the survival and growth of American sycamore (Platanus occidentalis L.) and willow oak (Quercus phellos L.) planted on an old field riparian area in the Virginia Piedmont. American sycamore seedlings subjected to greenhouse flood preconditioning had 25% greater height and willow oak seedlings grown under normal greenhouse conditions had 18% greater diameter, but these greenhouse adaptations did not confer greater survivability or growth after field planting. American sycamore seeds sourced from dry ecotypes were 14% taller than wet ecotype seeds, and willow oak acorns sourced from wet ecotypes were 11% taller than dry ecotype acorns, indicating that parental ecotype may influence survivability and growth. The combination of mounding site preparation and gallon planting stock increased mean survival to 100% and aboveground dry biomass (5.44 Mg/ha/yr) in American sycamore. Willow oak had 45% greater woody stem volume with mounding site preparation 80% greater woody stem volume with gallon and bare root planting stock. Tubeling planting stock provided significant benefit relative to the low planting stock cost for American sycamore, while bare root seedlings were shown to be an effective planting stock for willow oak. The use of appropriate ecotype seed sources, use of mounding mechanical site preparation techniques and planting of species appropriate planting stock increased survival and growth of common early and mid-successional Piedmont tree species on marginal agricultural lands. Treatments that appear to be economically viable for restoration and mitigation efforts could potentially offer other economic incentives such as short rotation woody crops and timber value, which might induce additional private landowners to attempt restoration efforts in marginal old field riparian areas. / Doctor of Philosophy / In order to offset the loss of wetlands due to development, strategies are needed to create wetlands in areas along streams that are unfarmed. Survival and growth of planted trees are commonly used to evaluate the success of these new wetland areas. The goal of this research is to provide alternative methods to increase survival and growth of two common trees planted in the Piedmont of Virginia. The results show that creating mounds of soil before planting trees and planting larger trees will increase tree survival and growth in these wetland areas. Landowners and land managers can use these methods to increase the value of unfarmed land along streams while also increasing water quality and providing habitat animals that use the streams and wetlands.

In west-central Alberta increased landscape fragmentation has lead to increased human use, having negative effects on wildlife such as the grizzly bear (<i>Ursus arctos</i> L.). Recently, grizzly bears in the Foothills Model Forest were found to select clear cuts of different age ranges as habitat and selected or avoided certain clear cuts depending on the site preparation process employed. Satellite remote sensing offers a practical and cost-effective method by which cut areas, their age, and site preparation activities can be quantified. This thesis examines the utility of spectral reflectance of SPOT-5 pansharpened imagery (2.5m spatial resolution) to identify and map 44 regenerating stands sampled in August 2005. Using object based classification with the Normalized Difference Moisture Index (NDMI), green, and short wave infrared (SWIR) bands, 90% accuracy can be achieved in the detection of forest disturbance. Forest structural parameters were used to calculate the structural complexity index (SCI), the first loading of a principal components analysis. The NDMI, first-order standard deviation and second-order correlation texture measures were better able to explain differences in SCI among the 44 forest stands (R2=0.74). The best window size for the texture measures was 5x5, indicating that this is a measure only detectable at a very high spatial resolution. Age classes of these cut blocks were analysed using linear discriminant analysis and best separated (82.5%) with the SWIR and green spectral bands, second order correlation under a 25x25 window, and the predicted SCI. Site preparation was best classified (90.9%) using the NDMI and homogeneity texture under a 5x5 window. Future applications from this research include the selection of high probability grizzly habitat for high spatial resolution imagery acquisition for detailed mapping initiatives.

In west-central Alberta increased landscape fragmentation has lead to increased human use, having negative effects on wildlife such as the grizzly bear (<i>Ursus arctos</i> L.). Recently, grizzly bears in the Foothills Model Forest were found to select clear cuts of different age ranges as habitat and selected or avoided certain clear cuts depending on the site preparation process employed. Satellite remote sensing offers a practical and cost-effective method by which cut areas, their age, and site preparation activities can be quantified. This thesis examines the utility of spectral reflectance of SPOT-5 pansharpened imagery (2.5m spatial resolution) to identify and map 44 regenerating stands sampled in August 2005. Using object based classification with the Normalized Difference Moisture Index (NDMI), green, and short wave infrared (SWIR) bands, 90% accuracy can be achieved in the detection of forest disturbance. Forest structural parameters were used to calculate the structural complexity index (SCI), the first loading of a principal components analysis. The NDMI, first-order standard deviation and second-order correlation texture measures were better able to explain differences in SCI among the 44 forest stands (R2=0.74). The best window size for the texture measures was 5x5, indicating that this is a measure only detectable at a very high spatial resolution. Age classes of these cut blocks were analysed using linear discriminant analysis and best separated (82.5%) with the SWIR and green spectral bands, second order correlation under a 25x25 window, and the predicted SCI. Site preparation was best classified (90.9%) using the NDMI and homogeneity texture under a 5x5 window. Future applications from this research include the selection of high probability grizzly habitat for high spatial resolution imagery acquisition for detailed mapping initiatives.

Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniv. / Härtill 4 uppsatser.

Thesis (M.S.)--University of Tennessee, Knoxville, 2008. / Title from title page screen (viewed on Sept. 23, 2009). Thesis advisor: Wayne K. Clatterbuck. Vita. Includes bibliographical references.

Bare-root Nuttall oak, Shumard oak, and swamp chestnut oak seedlings were planted on former agricultural fields in Mississippi to evaluate growth and survival following treatment by different combinations of mechanical site preparation and pre-emergent Oust XP® applications. Mechanical treatments included: (1) controls, (2) subsoiling treatment, (3) bedding treatment, and (4) combination plowing. Pre-emergent Oust XP® treatments included: (1) one-year Oust XP® applications and (2) two-year Oust XP® applications. Evaluations and measurements were performed over the course of three years. Results within this dissertation should be considered in the context of high quality former agricultural sites with silt loam soils. Seedling height and GLD increased each growing season. Height and GLD of seedlings were greater in bedded and combination plowed areas compared to control and subsoiled areas. Height and GLD were not different by Oust XP® application. However, seedling survival in two-year Oust XP® application areas was reduced compared to one-year Oust XP® application areas. Nuttall oak seedlings planted in bedded and combination plowed areas exhibited greater stem biomass compared to those planted in control or subsoiled areas. Seedlings planted in two-year Oust XP® areas exhibited greater stem and root biomass compared to those planted in areas receiving the one-year treatment. Better growth and biomass production in bedded and combination plowed areas would promote their use for site preparation on similar sites. While survival was lower in two-year Oust XP® treatment areas compared to one-year treatment areas, the difference would not warrant change in management strategy. Additionally, woody biomass was much greater in two-year Oust XP® areas. Thus, if cost is not prohibitive, treatment with two years of Oust XP® is recommended. The objective of the mixed species study was to establish baseline growth and survival data for mixed Nuttall oak and green ash plantations on former agricultural areas. Height and GLD for both species increased each growing season. Third-year survival was excellent at 96.0 percent. In conclusion, the mixture performed satisfactorily. Growth and survival were excellent, which indicates this mixture would be useful in afforesting similar former agriculture sites.

The Southeastern Lower Coastal Plain wet pine flats include thousands of acres of jurisdictional wetlands that are economically, socially, and environmentally important. These highly productive forests have been intensively managed as pine plantations for the past few decades. More recently, harvesting and site preparation practices have become a concern among natural resource managers because intensive forestry practices may alter soil physical properties and site hydrology. These alterations could decrease seedling survival, growth, and future site productivity. However, the effects of soil disturbance on long-term site productivity and the effects of amelioration techniques on site hydrology are uncertain. The overall objectives of this study were (1) to characterize disturbed forest soil morphology and physical properties, (2) to assess their impact on the processes that control site hydrology and site productivity, (3) to determine effects of harvesting and site preparation on site hydrology, specifically on the overall hydrological balance and on spatial and temporal patterns of surface water storage. The study site is located in an intensively managed loblolly pine (Pinus taeda L.) plantation in the lower coastal plain of South Carolina. This study was established in winter 1991, and dry- and wet-weather harvesting treatments were installed in summer 1993 and winter 1994, respectively. Bedding and mole channel/bedding treatments were installed in both dry- and wet-harvested plots in fall 1995. Soil profiles were described for a recently disturbed, deeply-rutted area, and 2-year-old deeply-rutted and churned areas, bedded and undisturbed areas. Intact soil core samples and composite loose soil samples were collected from each morphological section for soil physical characterizations. Automated weather station and wells were used to collect continuous climatic and surface water level data since 1996. Surface water levels were monitored monthly on a 20 x 20 m grid of 1-m wells since 1992. Total groundwater heads were determined from differential piezometer measurements at high and low elevation places in each treatment plot. Soil profile descriptions and soil physical property measurements indicated that significant amounts of organic debris were incorporated into the surface horizons, and subsurface soil horizons showed significant soil structural changes and increased redoximorphic features caused by soil disturbance. The disturbed soil layers in recently created traffic ruts consisted of exposed and severely disturbed subsurface soils, but this layer was naturally ameliorated 2 years after the disturbance. Bedding site preparation had little amelioration effects on the physical properties of surface soil horizons because the surface horizons already had some incorporation of organic debris. Overall, the main consequence of bedding in a disturbed wet site was to increase the aerated soil volume. The bedding appeared to have little effect on disturbed subsurface horizons. Groundwater head in the study site was constantly higher than -25 cm during the study period, which caused groundwater inflow when the surface water level was low. Frequent fluctuation of the surface water level and constant water supply from the groundwater probably explain the high productivity of the study site. Results of the annual water balance showed that surface soil water storage changes were very small, and annual precipitation and potential evapotranspiration were approximately equal. Silvicultural practices and minor topography on the study site had significant effects on the water balance because they influenced surface water level. Surface water hydraulic gradient evaluation and multivariate cluster analysis indicated that micro-site hydrology and water flow patterns were significantly altered by wet-weather harvesting and bedding site preparation, but overall site hydrology was not altered. Evaluation of predicted surface water level indicated that micro-topography and precipitation patterns had significant influences on surface water levels during the site establishment period. These results revealed that the hydrologic components of wetland delineation are complex in the wet pine flatwoods. / Ph. D.