Harvesting practices in the southern Appalachians have moved away from clearcutting in favor of variable retention harvesting systems. A study was initiated in 1995-8 to investigate the effects of retaining varying numbers of residual trees on regeneration in seven silvicultural treatments. A second study specifically focused on stump sprouting in only three of those treatments. The treatments for first study included: a clearcut, commercial harvest, leave-tree, shelterwood, group selection, midstory treatment, and an uncut control. The second only focused on the clearcut, leave-tree, and shelterwood. These treatments were implemented in seven stands in Virginia and West Virginia over two physiographic provinces, the Appalachian plateau and Ridge and Valley. The stands were even-aged oak dominated Appalachian hardwood stands on fair quality sites with average ages ranging from 63 to 100 yrs. Permanent plots were randomly located in each stand and all overstory trees (>5m tall) were inventoried and tagged prior to harvest. Regeneration was also quantified. Harvest occurred between 1995-8. For the current studies the plots were re-inventoried 9-11 years post-harvest and all regeneration in all treatments as well as stump sprouts in the selected treatments were quantified. The first study utilized a mixed model ANOVA to analyze five species groups: oak, maple, black cherry-yellow-poplar, miscellaneous, and midstory. Response variables included importance value, average height, and density compared within species group and among treatments. Differences between sprout and seedling origin regeneration were also investigated within species group among treatment. Results indicated that oak densities were similar in all of the treatments, and stump sprouts were larger and more frequent than seedlings. Maple exhibited an increase from pre-harvest overstory importance and exhibited competitive sprouting. The black cherry-yellow-poplar group had few but highly competitive sprouts and a considerable increase in seedling origin regeneration in all treatments. The miscellaneous species densities increased as well with more competitive sprouting in some treatments. The midstory species were excluded from the analysis as it was assumed these species would not occupy canopy positions in a mature stand. The second study investigated differences in the percent of stumps that sprouted and the number of sprouts per stump. The percent data were analyzed using a non-parametric one-way ANOVA and regression analysis, while the sprouts per stump data were compared in a mixed model ANOVA and regression. Species were combined into six groups: the red oak group, chestnut oak, red maple, white oak/hickory group, mixed mesic group, and midstory group. The plateau tended to have reduced sprouting compared to the Ridge and Valley for most species groups and treatments. The red oak group, chestnut oak, and red maple exhibited reduced sprouting with increased residual basal area. The mixed mesic group did not show any effect in sprouting related to residual basal area. Only chestnut oak showed fewer sprouts per stump as residual basal area increased. / Master of Science

The effects of seven silvicultural prescriptions were examined one full growing season post-treatment on five sites in the Ridge and Valley, Cumberland Plateau, and Allegheny Plateau of Virginia and West Virginia. Prescriptions were (1) control, (2) understory control with herbicide, (3) group selection, (4) high-leave shelterwood, (5) low-leave shelterwood, (6) leave tree, and (7) clearcut. The effects of each treatment on the vascular plant community were characterized by changes in species diversity, species composition, exotic species richness, Raunkiaer's life-forms, and growth-forms. Pre-treatment, baseline data, and a randomized block design ensured the precision of post-treatment comparisons. High-disturbance treatments (i.e., low-leave shelterwood, leave tree, clearcut) exhibited lower tree-stratum species richness than unharvested treatments. Prescriptions had no effect on shrub-stratum richness. Compared to the control, woody, herb-stratum richness was higher in harvested treatments. Non-woody herb-stratum richness was unaffected. No differences in herb-stratum species diversity were detected using Shannon's (exp H') or Simpson's (1/D) indices. Non-woody species richness per 2-ha treatment plot was significantly higher than the control for high-disturbance treatments. Pre- vs. post-treatment species composition was least similar for high-disturbance treatments, as measured by qualitative and quantitative community similarity indices. Exotic woody species richness was unaffected by treatment; however, non-woody exotic species were more prevalent in high-disturbance treatments. Hemicrytophytes replaced phanerophytes as the most important life-form for harvested treatments. Therophytes were more important in harvested treatments, while the proportion of cryptophtes and chamaephytes did not change in response to treatments. Tree and shrub growth-forms were less dominant in harvested treatments, while graminoids and annual/biennial forbs were more important for high-disturbance treatments. These data represent only the initial results of a long-term study designed to examine plant-community response to silviculture for one harvest rotation length. Long-term results will aid in devising management strategies that address concerns for biodiversity without devaluing traditional resource demands. / Master of Science

Tyrimų rezultate buvo nustatyti trako ir gyvosios dirvožemio dangos pokyčiai pušynuose po atvejinių kirtimų I atvejo Na, Nb, Nc, Lb augavietėse bei įvertinti pomiškio gausumo pokyčiai. Įvertinta gyvosios dirvožemio dangos įtaka paprastosios pušies savaiminukų gausumui po I kirtimų atvejo tirtose augavietėse. Įvertintos kirtaviečių ekologinės sąlygos pagal Elenbergo fitoindikacinės skalės indikatorines vertes skirtingose augavietėse. Nustatyta smiltyninio ir miškinio lendrūnų fitometrinių parametrų ir elementinės sudėties pokyčiai po atvejinių kirtimų I atvejo. Atliktais tyrimais nustatyti dirvožemio cheminių savybių pokyčiai. Palyginta plynųjų ir atvejinių kirtimų įtaka dirvožemio temperatūros ir drėgnio, mineralinio azoto, ir kvėpavimo intensyvumo pokyčiams. / Results of the research allowed determining the changes of undergrowth and ground vegetation in pine forest after the first step of shelterwood cuttings in Na, Nb, Nc and Lb sites and to evaluate the alterations of saplings abundance. The influence of ground vegetation on the abundance of Scotch Pine sapling after the first step of shelterwood cuttings in investigated sites was assessed. Ecological conditions of cutting sites in different soil sites were estimated according to Ellenberg’s indicator values for phytoindication. The alterations of morphometric indices and chemical composition of wood small-reed and rough small-reed after the first step of shelterwood cuttings were assessed. The changes of soil chemical characteristics were determined after investigation. The influence of clear cuttings and shelterwood cuttings on the alterations of soil moisture, temperature, mineral nitrogen and respiration intensity was compared.

The aim of this study is to investigate the possibilities of pine natural regeneration in different nature regions in the clear-cuts with main site types. The tasks of this work are: 1. to estimate a potential possibilities of pinewood natural regeneration; 2. to find out the ecological factors, that have a great influence on pine sprouts on the Na (dry not fertile), Nb (dry less than average fertile) and Lb (with excess water and less than average fertile) site types and to set their critical borders; 3. to find out the main economical factors, that promotes pine regeneration (site preparation, seed trees, shelter wood); 4. to prepare the recommendations to promote the pinewood natural regeneration. Recency and originality. This is the first investigations were made in complexly including the most common sites in Lithuania for pinewood (Na, Nb and Lb site types) in the three native regions covering largest part of Lithuania. This enables to make prognoses of pinewood regeneration in those regions on the mentioned site index. For the first time there were defined the sufficiency of the shelter-seed trees for regeneration and their distribution in a clear and step wise cutted areas to ensure the natural regeneration of pine. There were found that 2-3 point yield of pine seeds (under Capper) and on the time and in right way implemented encouragements, ensure natural pine regeneration after clear or step wise cuttings. Following the results, it was suggested to advance the... [to full text]

Magistro darbe nustatyta pušynų atvejinių kirtimų įtaka pomiškio formavimuisi Švenčionėlių miškų urėdijoje. Darbo objektas: Pomiškis atsikuriantis po atvejinių kirtimų Švenčionėlių miškų urėdijos pušynuose. Darbo tikslas: Nustatyti pušynų atvejinių kirtimų įtaką pomiškio formavimuisi. Darbo metodai: Nustatant pomiškio kiekį, išsilaikymą, kirtaviečių žolinės dangos poveikį pomiškiui, tyrimai atlikti septyniolikoje skirtingų metų supaprastintų atvejinių kirtimų (B. Labanausko) kirtavietėse, kur visos augavietės buvo Nbl (normalaus drėgnumo nederlingi dirvožemiai). Tyrimai vykdyti 2010 metais Švenčionėlių miškų urėdijos, Januliškio, Labanoro, Lakajų, Pasiaurės, Prūdiškės girininkijų miškuose. Patvirtinta metodika atlikti lauko tyrimai. Kiekviename sklype buvo parinktos 2 x 20 m juostos (40 m2), tolygiai išdėstytos sklype (vienodais atstumais sklypo įstrižainių kryptimis). Apskaitos juostoje aprašytas ir įvertintas pomiškis bei žolinė danga. Pomiškio medelių rūšys buvo registruojamos nurodant jų skaičių vienetais, o žolinės dangos rūšys – nurodant projekcinį padengimą procentais. Gauti duomenys užrašyti į iš anksto paruoštus duomenų rinkimo lapus. Darbo rezultatai: Tirtuose sklypuose, pušies savaiminukai gerai atžėlė 53 % visų sklypų. Patenkinamai atžėlė 35 % tirtų sklypų. 12 % tirtų sklypų neatitinka nuostatų, nes pušies savaiminukų skaičius hektare yra nepakankamas reikiamam pušies atžėlimui. Atvejinėse kirtavietėse nepageidaujamos medžių rūšys turi įtakos projektuojamų medžių... [toliau žr. visą tekstą] / In this master thesis was determined pine forest shelter wood cutting influence to understory formation in Švenčionėlių State forest Enterprice. The object of work: Understory, regenerating after shelter wood cutting in Švenčionėlių State forest Enterprice. The aim of work: To determine shelter wood cutting influence to understroy formation in pine forest. Methodology: By evaluating quantity of understory, survival, herbal plants influence to forest understory in cutting areas, the reasearch was performed in seventeen simplified shelter wood cutting areas with different cutting age, (B. Labanausko) where all sites were Nbl (regular moisture not fertile soils). The research was performed in 2010 year, in Švenčionėlių State forest enterprise, Januliškio, Labanoro, Lakajų, Pasiaurės, Prūdiškės forest districts. According to methodology, outdoor investigations were made. In each sample plot were chosen 2 x 20 m stripes (40 m2), gradualy located in a plot (by equal distances to plot diagonal directions). In sample plots understory and herbal cover were evaluated and described. Understory tree species were registered apiece, and herbal cover species were registered by indentifying projective cover of land in percentage. Data were recorded to prepared blanks. Results: Pine seedlings regenerated well in 53 % sample plots. Sufficiant regeneration (35 %) was found in 3 plots. 12 % of investigated plots had inadequate conditions, because amount of pine seedlings in one hektare... [to full text]

The regeneration in oak-dominated stands following five silvicultural treatments was examined on four sites in the mountains of Virginia and West Virginia. Treatments included: silvicultural clearcut, leave-tree, commercial clearcut, shelterwood, and group selection. The effects of harvesting were compared among sites and among treatments. Oak regeneration dominance, measured by the relative density of dominant and codominant oak regeneration, was the most important variable calculated from the data. Oak regeneration dominance varied by site, but did not vary by silvicultural treatment; all treatments resulted in relatively low numbers. Therefore, the silvicultural treatments used here were not enough to overcome the site specific limitations to successful oak regeneration. Oak species also seemed to be less important in the regenerating stands than in their parent stands. The biggest losses in oak importance occurred on the intermediate and high quality sites; competitive oak regeneration was relatively scarce on two of the three sites with an oak site index (base age 50) of over 70 ft. Multiple linear regression analysis was used to identify the factors controlling oak regeneration at a smaller scale. The most important variables were those that described the oak stump sprouting potential, the understory and overstory oak component in the pre-harvest stand, post-harvest light and soil nitrogen levels. / Master of Science

<p>  </p> <p>Alterations to the historic fire regime have contributed to widespread regeneration failure in <em>Quercus</em> L. (oak) forests of the eastern United States. Composition has shifted from <em>Quercus</em> and other fire-adapted species to dominance by mesophytic species. While land managers often focus efforts on restoring <em>Quercus</em> regeneration, the herbaceous layer experiences reduced cover and diversity of herb and graminoid species resulting from the increased woody stem density in fire-suppressed forests. Declining abundance of <em>Quercus</em> species and diversity in the herbaceous layer reduce the overall habitat quality and ecosystem functions provided by the forest. A combination of overstory harvests and prescribed burning are often conducted to restore the plant community in <em>Quercus</em> forests affected by mesophication. Initiated in 2010, our study on the Hoosier National Forest in Indiana conducted shelterwood and midstory (mechanical, chemical, or none) harvests followed by prescribed burning on a less productive site, while leaving a more productive site unburned. Our objective was to evaluate the survival and competitive response of <em>Quercus</em> spp. within the regeneration layer and whether diversity and cover increased in the herbaceous layer following treatments. Using nested circular plots, we measured seedling survival and resprout response, in addition to regeneration density before and after treatments. We measured the percent cover of herbaceous-layer species within quadrats and calculated species richness, evenness, and diversity. Using multiple mixed-effects models, ANOVA, and NMDS ordination, we evaluated woody species regeneration and herbaceous-layer composition before and after treatments. Post-treatment, monitored <em>Quercus</em> spp. seedlings at the burned site displayed greater survival (> 94%) and resprouting (> 92% of monitored stems), which exceeded most competing species, including<em> Acer</em> spp. (~ 59% survival and resprouting) and <em>Fraxinus americana </em>(72% survival and resprouting). <em>Q. alba</em> seedling (< 3.8 cm DBH) densities doubled after burning; it was one of the most abundant species (9,864 stems ha-1) at the burned site. NMDS ordination indicated a clear shift in regeneration species composition with the burn driving a shift away from mesophytic species towards greater importance of <em>Quercus</em> species. Additionally, our burned site had significantly increased herbaceous-layer richness, Shannon diversity index, and total cover compared to pre-treatment. Percent cover increased across all plant functional groups within the herbaceous layer, with trees/shrubs exhibiting the greatest increase. Herbaceous-layer composition at the burned site significantly shifted toward greater importance of graminoids and herbs post-treatment. Post-treatment, the unburned site contained fewer, and less competitive, <em>Quercus</em> seedlings compared to non-<em>Quercus</em> competitors and displayed no significant compositional shifts in seedling species composition post-harvest. Our unburned site exhibited significant, but minor, increases in herbaceous-layer richness, evenness, diversity, and total cover. Herbaceous-layer composition at the unburned site was significantly different post-treatment, shifting towards greater importance of vines, trees/shrubs, and herbs. The more-productive unburned site would likely require multiple burns to produce adequate competitive <em>Quercus</em> seedlings to perpetuate dominance in the developing stand. Burning would also likely result in greater increases in herbaceous-layer diversity compared to harvesting alone. Conversely, the shelterwood, followed by a single burn, on the less productive site had a more substantial effect on the herbaceous layer, and likely produced an adequate density of <em>Quercus</em> reproduction to ensure future dominance by the genus.</p>

<p dir="ltr">For several decades, the ecological dominance of white oak (<i>Quercus alba</i>) has been declining throughout the species’ native range in eastern North America with failure to recruit new individuals into the overstory. White oak’s decline is concerning as the species is of great cultural, ecological, and economic value. Planting artificial regeneration is one approach to bolstering flagging natural white oak regeneration insufficient in vigor or quantity to supplant mature canopy white oak. Shelterwood harvests and artificial regeneration alone or in combination are frequently suggested to be an effective means of securing sufficient white oak regeneration in central hardwood understories. Because there is a much more comprehensive body of work examining northern red oak (<i>Quercus rubra</i>) than white oak artificial regeneration, managerial prescriptions for artificial regeneration of white oak are commonly generalized from northern red oak prescriptions. If the two species are silvically different, however, they should be managed differently to achieve maximum effectiveness of regenerative prescriptions.</p><p><br></p><p dir="ltr">I conducted both a silvicultural field trial and a more controlled shade and competition study to examine artificial white oak regeneration responses to light and competition gradients. In the silvicultural field trial, I tested the impacts of varied lengths of competition control, geographical seed source, and canopy cover on growth and survival of artificial white oak regeneration within an expanding shelterwood system. After three growing seasons, my results indicated that seedlings grow and survive at the greatest rates in areas of up to approximately 50% canopy closure, or conditions found in harvest gaps.</p><p dir="ltr">In a shade and competition study, I compared artificial northern red oak and white oak growth, morphology, and physiology responses to three light levels (10% or low, 30% or medium, and full sun or high) under the presence or absence of an invasive competitor (Amur honeysuckle (<i>Lonicera maackii</i>)). After two years, my results indicated that medium light levels resulted in the greatest height and diameter growth as well as the greatest nonstructural carbohydrate amounts in both root and shoot organs of both species. Interestingly, my physiology results indicated that northern red oak seedlings displayed lower light compensation points and greater quantum yields than white oak seedlings. These traits potentially indicate greater shade tolerance of northern red oak than white oak. Further, white oak foliar nitrogen in shaded treatments, quantum yield, and light compensation points were impacted more severely by competition than equivalent northern red oak measures, indicating that white oak seedlings may not be as well equipped to handle invasive competition pressures. These results indicate that these two upland oak species are fundamentally different, and these differences should be considered when writing management prescriptions.</p>

The vegetation responses to seven silvicultural treatments one growing season after harvesting were examined on seven sites in the southern Appalachian mountains of Virginia and West Virginia. Treatments included: 1) control, 2) understory control by herbicide, 3) group selection, 4) high-leave shelterwood, 5) low-leave shelterwood, 6) leave tree, and 7) clearcut. The effects of harvesting were compared between treatments and between pre-harvest and post-harvest samplings. Species richness, percent cover, and local species extinctions were calculated for sample plots ranging in size from 1m2 to 2 ha. Vegetation richness and cover increased with increasing harvest intensity. Local species extinctions were similar in the control and disturbed treatments. Additional analyses were performed using the control, high-leave shelterwood, and clearcut on five of the seven sites to determine the relationships between soil, litter, and other environmental characteristics and vegetation in the herbaceous layer (<1 m in height). Multivariate analysis techniques were used to analyze average differences in species abundance between pre-harvest and post-harvest and to relate post-harvest vegetation to microsite characteristics. Regional-scale differences in site location were more important in explaining the presence of a species than were environmental characteristics. Within a region, species primarily were distributed along a light/litter weight gradient and secondarily along a soil properties and nutrient gradient. / Master of Science

No description available.