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Shortleaf pine (Pinus echinata Mill.) has been planted in the western part of the Southeastern United States. The United States Department of Agriculture (USDA) Forest Service Forest Vegetation Simulator (FVS) is the only currently widely available comprehensive yield prediction system for these plantations. As an initial attempt to determine optimal thinning regimes, predictions were obtained for planting densities of 988, 1,483, and 1,977 seedlings per hectare (400, 600, and 800 seedlings per acre) for site indexes of 13.72, 18.29, and 22.86 m (base age 25) (45, 60, and 75 ft, respectively). Total discounted reforestation costs were calculated using a 5% interest rate. Projections were obtained for 80 years and a thinning 'trigger' of 27.55 square meters per hectare [120 square feet of basal area (at a height of 4.5 feet aboveground) per acre] was used along with a residual stand density of 16.07 square meters per hectare (70 square feet per acre). Financial assessments were conducted by combining the discounted reforestation costs and FVS projections with one of three sets of stumpage revenues; Current, Reasonable, and Optimum. For lower site qualities (e.g. SI 13.72), when using this particular thinning regime, positive financial returns were not observed regardless of the stumpage prices. On higher quality sites (e.g. SI 22.86), given FVS projections and the selected thinning regime, positive financial returns will likely be observed. For medium quality sites (e.g. SI 18.29), if stumpage markets improve (e.g. Reasonable and Optimum sets of stumpage revenues), growth rates on these sites may be enough to produce positive financial returns. For this thinning regime (27.55 trigger and 16.07 residual), an optimal planting density is likely around 1,236 to 1,359 seedlings per hectare (500 to 550 seedlings per acre). However, a much more complete assessment of thinning regimes needs to be conducted and calibrated FVS projections should be used. Keywords: Shortleaf pine, Optimal Planting Density, Stumpage Revenue, Forest Vegetative Simulator, INTRODUCTION The historical range of shortleaf pine (Pinus echinata Mill.) includes much of the western half of the southeastern United States as well as the southeastern part of Missouri and [...]

Novel ecosystems occur when new combinations of species appear within a particular biome. They typically result from direct human activity, environmental change, or the impacts of introduced species. In this paper, we argue that considering commercial tree plantations as novel ecosystems has the potential to help policy makers, resource managers, and conservation biologists better deal with the challenges and opportunities associated with managing plantations for multiple purposes at both the stand and landscape scales. We outline five inter-related issues associated with managing tree plantations, which are arguably the largest form of terrestrial novel ecosystem worldwide. This is to ensure that these areas contribute significantly to critical ecosystem services, including biodiversity conservation, in addition to their wood production role. We suggest that viewing tree plantations as novel socioecological systems may free managers from a narrow stand-based perspective and having to compare them with natural forest stands. This can help promote the development of management principles that better integrate plantations into the larger landscape so that their benefits are maximized and their potential negative ecological effects are minimized. Key words: novel ecosystems, tree plantations, novel management, landscape conservation, biodiversity conservation, forest management. Des ecosystemes nouveaux apparaissent lorsque de nouvelles combinaisons d'especes se forment dans un biome particulier. Ils resultent en general directement de l'activite humaine, de changements environnementaux ou des impacts d'especes introduites. Dans cet article, nous soutenons que le fait de considerer les plantations forestieres commerciales comme des ecosystemes nouveaux a le potentiel d'aider les decideurs politiques, les gestionnaires des ressources et les biologistes de la conservation a mieux faire face aux defis et opportunites associes a la gestion des plantations a des fins multiples tant a l'echelle du peuplement que du paysage. Nous presentons cinq enjeux interdependants associes a la gestion des plantations forestieres qui constituent sans doute la plus vaste forme d'ecosysteme terrestre nouveau dans le monde. Le but est de s'assurer que ces zones contribuent de facon significative aux services essentiels de l'ecosysteme, incluant la conservation de la biodiversite en plus de leur role dans la production de matiere ligneuse. Nous croyons que le fait de considerer les plantations forestieres comme des ecosystemes socio-ecologiques nouveaux peut liberer les gestionnaires d'une perspective etroite fondee sur le peuplement et les exempter d'avoir a prendre comme point de comparaison des peuplements de foret naturelle. Cela peut contribuer a promouvoir le developpement de principes d'amenagement qui integrent mieux les plantations dans le paysage plus large de telle sorte que leurs benefices soient maximises et que leurs impacts ecologiques potentiellement nefastes soient minimises. [Traduit par la Redaction] Mots-cles: ecosystemes nouveaux, plantations forestieres, amenagement nouveau, conservation du paysage, conservation de la biodiversite., Introduction There are many definitions of and reasons for establishing commercial tree plantations. For the purposes of this paper, we define commercial plantations as 'Stands of trees of native or [...]

Forest growth and yield models that incorporate common silvicultural practices are essential for practicing intensive forest management. We present models for growth response to a wide range of silvicultural treatments in loblolly pine (Pinus taeda L.) plantations. Baseline models for basal area, dominant height, and survival were fitted using data from across the southeastern United States. Growth models for treated stands were developed by multiplying baseline models with modifier response functions accounting for effects of thinning, fertilization, and control of competing vegetation. Response to early control of competing vegetation was incorporated into baseline models through multiplier factors that were calculated from growth differences between treated and untreated stands. The thinning response function included duration and rate parameters and was sensitive to stand age at the time of thinning, time since thinning, and intensity of thinning. Fertilization response functions were based on the Weibull distribution; the magnitude of responses varies with time since application of fertilizers, type of fertilizer, and rate of application. A difference function, derived from a differential equation with age, initial stand density, and site index as predictors, served as the baseline survival model. The survival model was adjusted for thinning treatment by including an additional independent variable that represents thinning intensity. The resulting models were able to predict growth response when single, as well as multiple, treatments were applied. Key words: modeling, growth and yield, thinning, vegetation management, fertilization, Pinus taeda. Des modeles de croissance et de production forestiere qui tiennent compte des pratiques sylvicoles courantes sont essentiels pour realiser un amenagement forestier intensif. Nous presentons des modeles d'impact d'une large gamme de traitements sylvicoles sur la croissance dans des plantations de pins a encens (Pinus taeda L.). Nous avons ajuste des modeles de base pour la surface terriere, la hauteur dominante et la survie a l'aide de donnees couvrant le sud-est des Etats- Unis. Les modeles de croissance des peuplements traites ont ete mis au point en multipliant les modeles de base par des fonctions de reponse modificatrices qui tiennent compte des effets de l'eclaircie, de la fertilisation et de la maitrise de la vegetation concurrente. La reaction a la maitrise precoce de la vegetation concurrente a ete introduite dans les modeles de base par des facteurs multiplicatifs calcules a partir de differences de croissance entre les peuplements traites et non traites. La fonction de reaction a l'eclaircie incluait des parametres de duree et de taux, et est sensible a l'age du peuplement au moment de l'eclaircie, au temps ecoule depuis l'eclaircie et a l'intensite de l'eclaircie. Les fonctions de reaction a la fertilisation etaient fondees sur la distribution de Weibull alors que l'amplitude des reactions varie en fonction du temps ecoule depuis l'application des fertilisants, le type de fertilisant et le taux d'application. Nous avons utilise un modele de base pour la survie fonde sur une fonction de difference, derivee d'une equation differentielle et ayant comme predicteurs l'age, la densite initiale du peuplement et l'indice de qualite de station. Le modele de survie a ete ajuste pour le traitement d'eclaircie en introduisant une variable independante supplementaire representant l'intensite de l'eclaircie. Les modeles obtenus pouvaient prevoir la reaction de croissance lorsque des traitements simples ou multiples etaient appliques. [Traduit par la Redaction] Mots-cles : modelisation, croissance et production, eclaircie, maitrise de la vegetation concurrente, fertilisation, Pinus taeda., Introduction Growth and yield models that quantify forest stand dynamics have been widely used in forest operations and management as an effective tool in decision making. Silvicultural practices such as [...]

The synchronization of nutrient release and demand in early stand establishment is important to maximizing resource use in forest plantations. We explored the impacts of forest floor manipulations on the dynamics of forest floor and mineral soil nutrient pools in a Pinus taeda L. plantation in North Carolina prior to and during 2 years following harvest and replanting. We present a novel method to estimate forest floor decomposition that avoids the exclusion of large detritivores. Decomposition and nutrient release rates from the forest floor were higher than rates typically observed in older stands (averaging 81% mass loss and 75% N loss across treatments over the 2-year period), highlighting the potential importance of the forest floor nutrient pool in early stand nutrition. Doubling the forest floor increased available C, N, and P pools in the mineral soil 46%, 47%, and 49%, respectively. Incorporating the forest floor into mineral soil through mixing had only transient positive effects on nutrient pools. Across treatments, an expected postharvest flush of soil available N was observed; however, removing the forest floor caused an earlier flush of available N in comparison with the control treatment, and doubling the forest floor caused a year delay in maximum N availability, better synchronizing the site's available N with stand demand. Key words: Assart effect, forest floor manipulations, Pinus taeda, forestry, nutrient dynamic. La synchronisation de la disponibilite et de la demande des nutriments tot lors de l'etablissement du peuplement est importante pour maximiser l'utilisation des ressources dans les plantations forestieres. Nous avons etudie les impacts des manipulations de la couverture morte sur la dynamique des bassins de nutriment de la couverture morte et du sol mineral dans une plantation de Pinus taeda L., en Caroline du Nord, avant et durant les deux annees qui ont suivi la recolte et la replantation. Nous presentons une nouvelle methode pour estimer la decomposition de la couverture morte sans exclure de larges detritivores. Les taux de decomposition et de liberation des nutriments dans la couverture morte etaient plus eleves que les taux typiquement observes dans les peuplements plus vieux (atteignant en moyenne 81% de perte de masse et 75% de perte de N dans l'ensemble des traitements sur une periode deux ans), faisant ressortir l'importance potentielle des bassins de nutriment de la couverture morte pour la nutrition du jeune peuplement. Le doublement de la couverture morte a augmente la disponibilite des bassins de C, N et P dans le sol mineral de respectivement 46, 47 et 49%. L'incorporation de la couverture morte dans le sol mineral en les melangeant n'a eu que des effets temporaires sur les bassins de nutriment. La liberation prevue d'une grande quantite de N disponible dans le sol a ete observee apres la recolte dans l'ensemble des traitements. Cependant, l'elimination de la couverture morte a entraine la mise en disponibilite plus precoce d'une grande quantite de N comparativement au traitement temoin et le doublement de la couverture morte a retarde d'un an la disponibilite maximum de N, entrainant une meilleure synchronisation de la disponibilite de N dans la station avec la demande du peuplement. [Traduit par la Redaction] Mots-cles: effet du a l'essartage, manipulations de la couverture morte, Pinus taeda, foresterie, dynamique des nutriments., Introduction Litterfall inputs in forests accumulate over time to form a forest floor layer (Switzer and Nelson 1972; Berg 1986) that is an important organic matter and nutrient pool potentially [...]

Afforestation and reforestation are considered important tools for mitigating fossil fuel emission; however, establishment of plantations necessarily involves several silvicultural treatments that may influence soil organic C sequestration and, potentially, its relative stability. An experimental design established 20 yr ago, consisting of plantations of white pine (Pinus strobus L.) and white spruce [Piceaglauca (Moench) Voss] was used to determine midterm impacts of blade scarification, fertilization, application of an herbicide, and tree species on soil C stocks and on the fraction of labile C determined by measurement of C mineralization on laboratory incubations. Twenty years after treatment, blade scarification had the greatest effect on soil organic C stock and stability. Carbon content was 54.2% lower in the F/H layer (equivalent to Oi and Oe/Oa layers) of blade-scarified plots compared with plots without blade scarification. Effects on the mineral soil layers were less obvious and partly mitigated by the addition of fertilizer on the surface. Blade scarification affected the general quality of C in the F/H layer because it significantly increased by 21.1% the fraction of labile C to total C; nevertheless, labile C content was 51.9% lower in the blade-scarified treatment. Vegetation control by herbicide as well as tree species had minor effects on C stocks and stability. A 9.0% decrease in mineral soil C content was observed with vegetation control. The F/H layer C concentration was 18.6% higher under white spruce than under white pine but these differences did not lead to a difference in C content. The small effects of treatments on surface mineral soil C could be explained by the limited capacity of this coarse-textured soil to sequester more silt- and clay-associated C. doi: 10.2136/sssaj2009.0273

Problem statement: Large scale plantation of oil palm trees requires on-time detection of diseases as the ganoderma basal stem rot disease was present in more than 50% of the oil palm plantations in Peninsular Malaysia. Approach: To deal with this problem, airborne hyperspectral imagery offers a better solution in order to detect and map the oil palm trees that were affected by the disease on time. Airborne hyperspectral can provide data on user requirement and has the capability of acquiring data in narrow and contiguous spectral bands which makes it possible to discriminate between healthy and diseased plants better compared to multispectral imagery. By using vegetation indices and red edge techniques, the condition of oil palm trees could be determined accurately. Results: Generally, all of these techniques showed better results as they could give accuracy between 73 and 84%. The highest accuracy was achieved by using Lagrangian interpolation technique with 84% of overall accuracy. Conclusion/Recommendations: The red edge based techniques were more effective than vegetation indices in detecting Ganoderma-infected oil palm trees plantation since there were three out of four techniques that could yield high accuracy results. Key words: Airborne sensor, oil palm, plant stress, vegetation indices, red edge, INTRODUCTION Dealing with disease problem in oil palm plantation involves a variety of curative measures in which disease detection and mapping play a central role. Hyperspectral remote sensing data offer [...]

The impacts of plantation forest management on soil C stocks in New Zealand need to be better understood for the purposes of C accounting under the Kyoto Protocol. We investigated the impacts of three harvest residue management treatments on C and N stocks in a scoriaceous forest soil: whole-tree harvesting plus forest floor removal, whole-tree harvesting, and stem-only harvesting. Volumetric samples were collected from the forest floor and three mineral soil depth increments (0-0.1, 0.1-0.2, and 0.2-0.3 m) 16 to 17 yr after harvesting. Both fine (2-mm) fractions of the mineral soil were analyzed. No significant impacts on stocks of C and N were observed in the mineral soil fine fraction. Averaged across treatments, the 0-to 0.3-m mineral soil coarse fraction contained 5.2 [+ or -] 0.52 Mg C [ha.sup.-1], representing 25% of total mineral soil C, with most derived from the fine-earth-coated scoria gravel. The inclusion of the coarse fraction stocks enabled the detection of significant treatment effects. Stem-only harvesting (residue retention) had significantly larger C stocks in the 0-to 0.1-m total mineral soil (fine + coarse fractions), forest floor, and total soil (forest floor + 0-0.3-m total mineral soil) pools than whole-tree harvesting (residue removal) plus forest floor removal. We recommend the retention of both harvest residues and forest floor materials for the maintenance of soil C stocks in plantation forests. Detection of residue management impacts on C stocks in soils with vesicular gravels may require analysis of the coarse fraction. Abbreviations: FE whole-tree harvesting plus forest floor removal; FH, fermented or humic; L, litter; OM, organic matter; SO, stem-only harvesting; WT, whole-tree harvesting.

One of the major challenges in oil palm plantations today is proper interpretation of yield maps for site-specific management and development of classified management zone maps for its efficient management. A study was conducted on an on-going fertilizer response trial in Sabah, Malaysia to examine the possibility of converting spatio-temporal yield maps of oil palm to classified management zone maps for practical management purposes. Two clusters of palms were selected for the study; with and without N fertilizer applications for the past 10 years. Fresh fruit bunch (ffb) yields were summarized on an annual basis. Point kriging method of geostatistics was used to interpolate ffb yields at unsampled locations. A classified management zone map was developed based on the spatial and temporal stability yield maps from 1992-1999. Nine management zones were derived form the spatio-temporal features in the ffb yield variations for decision making. Two management zones of high, stable yields and high, fairly stable yields and 4 management zones of moderate, stable yields; moderate, fairly stable yields; moderate, unstable yields; and low, unstable yields were then demarcated from area with and without N applications for practical management purposes. The results demonstrate the potential of transforming spatial and temporal stability of ffb yield maps from multi-year yield data to practical classified management zone maps for site-specific oil palm management particularly for fertilizer application. However, the potential of misinterpretation of yield maps can be high if limited data are available. Further work is necessary to ascertain the minimum number of palms and years required for the generation of meaningful yield maps and management zones. Keywords: Temporal variability, spatial variability, nitrogen fertilizer, oil palm yield, Malaysia, oil palm yield management maps, INTRODUCTION The ffb yields of oil palm are harvested over extended periods during the cropping cycle. This crop is known to exhibit high spatial and temporal yield variation (1), (2), [...]

Abstract: Swiss needle cast (SNC) causes premature loss of foliage and subsequent growth decline in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco). Although the mechanisms leading to this growth decline include loss [...]

The British Imperial government disposed of the plantations in Cameroon in 1924 to the Germans due to the British monied groups' apparent lack of interest because of the Mandated status of British Cameroon. The decision came after a series of conflicting proposals regarding the future of the plantations. An earlier plan favoring the distribution of the plantations among the local peasants was discarded as the government was afraid of a financial burden.

Post-revolutionary America reflected the conflict between change and continuity, especially in South Carolina and Georgia. Plantation owners retained slaves after 1783, using them to experiment with tidal irrigation and to cultivate rice. This increased the risk of flooding and caused saltwater to seep into plantation soil, destroying rice crops. A parallel is made between slavery and human nature where whites questioned the ethical aspects of reordering nature using slave labor.

The newest tung tree on the scene, Anna Bella, may herald a new generation of ornamental tung tree varieties suitable for landscape uses in the U.S. Gulf Coast. From the [...]