Foliar chemical concentrations, growth, and site productivity relations in western red cedar

Important site and tree characteristics of western red cedar (Thujaplicata Donn ex D. Don) were examined in 19 natural stands in the coastal and interior zones of western Washington and Oregon, U.S.A., and in western Vancouver Island, British Columbia, Canada. The stands occurred at various elevations and on different soil types and differed in age, soil pH, and associated plant species. Current-year foliage was collected during the winter and concentrations of N, P, K, S, Ca, Mg, Fe, Mn, B, Zn, Cu, Mo, Al, and the chlorophylls were determined. Mean terminal growth during the previous 3 years and site index at 50-year breast-height age were calculated for each stand. Site index ranged from 18 to 26 m. Terminal growth and foliar concentrations of the macronutrients, micronutrients, Al, and the chlorophylls varied among the 19 sites and between the two zones. Compared with known values for the most common associated conifers, foliar concentrations of red cedar were especially low in Mn and Al and high in Ca and Mo. Site index was correlated positively with N, the chlorophylls, S, Cu, and B, and negatively with Fe and Al. Also, N was positively correlated with the chlorophylls and with some of the other nutrients; there were many correlations among the nutrients and between some nutrients and soil pH or stand age. The data obtained provide base-line information for future analytical work with red cedar foliage. In addition, results suggest that (i) nutrient management strategies in western red cedar stands may differ from those for other conifers and different strategies may be necessary for the coastal and interior zones, (ii) productivity of red cedar may be improved by cultural treatments, including fertilization, which would enhance levels of chlorophyll as well as some essential elements (N, S, P, B, and Mo) in the foliage, (iii) levels of some chemicals in the foliage, such as N, chlorophyll, S, and B, may be useful as indicators to assess site quality for red cedar production, and (iv) chlorophyll may be used as a simple means to estimate N status of red cedar.

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Growth and foliar nutrient concentrations of Pacific silver fir

Canadian Journal of Forest Research ◽

10.1139/x89-218 ◽

1989 ◽

Vol 19 (11) ◽

pp. 1429-1435 ◽

Cited By ~ 7

Author(s):

M. A. Radwan ◽

M. D. Murray ◽

J. M. Kraft

Keyword(s):

Site Index ◽

Site Quality ◽

Nutrient Concentrations ◽

Future Research ◽

Silver Fir ◽

Base Line ◽

Foliar Nutrient ◽

Foliar Concentrations ◽

Foliar Nutrient Concentrations ◽

Natural Stands

Nineteen natural stands of Pacific silver fir (Abiesamabilis (Dougl.) Forbes) were assessed for selected site and tree characteristics. The stands, located throughout western Washington, were 26 to 37 years old; they occurred at various elevations (110–1300 m) and on different soil types, and varied greatly in associated plant species. Site index at 50 years breast-high age ranged from 12 to 24 m. Terminal growth per year during the previous 3 years, needle number per centimetre of twig tissue, needle weight and area, and foliar concentrations of 13 elements varied among the 19 stands. Compared with associated western conifers, silver fir had moderate terminal growth, larger and heavier needles, more needles per centimetre of twig tissue, and lower foliar concentrations of N, S, and Mg. There were many significant correlations among the different variables. The foliar nutrient data obtained provide base-line information for future research in nutrition and fertilization of silver fir. These data and the significant correlations between nutrients and site-stand characteristics suggest that (i) silver fir may be more efficient than some western conifers in use of some nutrients, (ii) productivity of silver fir may be improved by application of certain fertilizers; fertilization may be particularly effective during the seedling stage when growth is typically slow, and (iii) levels of some foliar nutrients may be useful as indicators of site quality for silver fir production.

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Influences of Forest Type, Stand Age, and Weather on Deer Weights and Antler Size in the Southern Appalachians

Southern Journal of Applied Forestry ◽

10.1093/sjaf/21.1.11 ◽

1997 ◽

Vol 21 (1) ◽

pp. 11-18 ◽

Cited By ~ 4

Author(s):

William M. Ford ◽

A. Sydney Johnson ◽

Philip E. Hale ◽

James M. Wentworth

Keyword(s):

Age Structure ◽

Forest Type ◽

Site Index ◽

Forest Stand ◽

Site Quality ◽

Stand Age ◽

Southern Appalachians ◽

Study Region ◽

Pinus Spp ◽

Percent Area

Abstract We analyzed correlations of forest type, age structure, and site index data with weights and antler characteristics of yearling white-tailed deer (Odocoileus virginianus) bucks from specific localities in the Chattahoochee, Cherokee, Nantahala, and Pisgah national forests in Georgia, Tennessee, and North Carolina. Areas in the northern part of the study region produced larger deer with larger antlers than those in the southern portion of the region. These northern areas differed from those to the south in having more diverse ownership and land use and in origins of deer stock. Weights and antler characteristics were significantly correlated (P < 0.05) with percent area in the cove hardwood type, but otherwise were poorly correlated with forest stand type and site index. Percent area in young (0-8 yr old) cove hardwood and in mid-successional (9-20 and 21-40) cove hardwood, pine (Pinus spp.), and upland oak (Quercus spp.) were significantly correlated (P < 0.05) with deer variables, particularly in years following a poor mast crop. Much of the quantifiable habitat influences on deer in the Southern Appalachians probably is masked by low deer densities and the small site quality differences among areas examined. Because much of the forest consists of mature mast-producing oaks and abundant forage is produced in both mature and younger aged stands, deer numbers seem to be below any threshold of quantifiable effects due to forest stand age structure. South. J. Appl. For. 21(1):11-18.

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Generalized Nonlinear Mixed-Effects Individual Tree Diameter Increment Models for Beech Forests in Slovakia

Forests ◽

10.3390/f10050451 ◽

2019 ◽

Vol 10 (5) ◽

pp. 451 ◽

Cited By ~ 1

Author(s):

Ram P. Sharma ◽

Igor Štefančík ◽

Zdeněk Vacek ◽

Stanislav Vacek

Keyword(s):

Basal Area ◽

European Beech ◽

Site Index ◽

Development Stage ◽

Mixed Effects ◽

Site Quality ◽

Stand Age ◽

Sample Plot ◽

Individual Tree ◽

Diameter Increment

Individual tree growth and yield models precisely describe tree growth irrespective of stand complexity and are capable of simulating various silvicultural alternatives in the stands with diverse structure, species composition, and management history. We developed both age dependent and age independent diameter increment models using long-term research sample plot data collected from both monospecific and mixed stands of European beech (Fagus sylvatica L.) in the Slovak Republic. We used diameter at breast height (DBH) as a main predictor and other characteristics describing site quality (site index), stand development stage (dominant height and stand age), stand density or competition (ratio of individual tree DBH to quadratic mean diameter), species mixture (basal area proportion of a species of interest), and dummy variable describing stand management regimes as covariate predictors to develop the models. We evaluated eight versatile growth functions in the first stage using DBH as a single predictor and selected the most suitable one, i.e., Chapman-Richards function for further analysis through the inclusion of covariate predictors. We introduced the random components describing sample plot-level random effects and stochastic variations on the diameter increment, into the models through the mixed-effects modelling. The autocorrelation caused by hierarchical data-structure, which is assumed to be partially reduced by mixed-effects modelling, was removed through the inclusion of the parameter accounting for the autoregressive error-structures. The models described about two-third parts of a total variation in the diameter increment without significant trends in the residuals. Compared to the age independent mixed-effects model (conditional coefficient of determination, R c 2 = 0.6566; root mean square error, RMSE = 0.1196), the age dependent model described a significantly larger proportion of the variations in diameter increment ( R c 2 = 0.6796, RMSE = 0.1141). Diameter increment was significantly influenced differently by covariate predictors included into the models. Diameter increment decreased with the advancement of stand development stage (increased dominant height and stand age), increasing intraspecific competition (increased basal area proportion of European beech per sample plot), and diameter increment increased with increasing site quality (increased site index) and decreased competition (increased ratio of DBH to quadratic mean diameter). Our mixed-effects models, which can be easily localized with the random effects estimated from prior measurement of diameter increments of four randomly selected trees per sample plot, will provide high prediction accuracies. Our models may be used for simulating growth of European beech irrespective of its stand structural complexity, as these models have included various covariate variables describing both tree-and stand-level characteristics, thinning regimes, except the climate characteristics. Together with other forest models, our models will be used as inputs to the growth simulator to be developed in the future, which is important for decision-making in forestry.

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Assessing site form as an indicator of site quality in even-aged Pinus radiata D. Don stands in north-western Spain

Annals of Forest Science ◽

10.1007/s13595-019-0904-1 ◽

2019 ◽

Vol 76 (4) ◽

Cited By ~ 1

Author(s):

Juan Alberto Molina-Valero ◽

Ulises Diéguez-Aranda ◽

Juan Gabriel Álvarez-González ◽

Fernando Castedo-Dorado ◽

César Pérez-Cruzado

Keyword(s):

Pinus Radiata ◽

Goodness Of Fit ◽

Model Fitting ◽

Site Index ◽

Site Quality ◽

Stand Age ◽

Fit Statistics ◽

Dominant Height ◽

Western Spain ◽

North Western

Abstract Key message Site form and site index have shown similar precision for estimating site quality in even-agedPinus radiataD. Don stands in north-western Spain. Additionally, SF presents the advantage that it does not require stand age information and can therefore be used in a wider set of situations in the forestry practice. Context Estimation of site quality is essential for characterizing, monitoring and predicting forest resources. Site index (i.e. the dominant height of the stand at a reference age) is ordinarily used to estimate site quality; however, this index is only useful for even-aged stands of known age. By contrast, SF is age-independent as it uses the dominant height of the stand at a reference dominant diameter. Aims The aim of this study was to compare the performance of SF and SI for site quality estimation in even-aged P. radiata stands. Methods Dynamic equations derived with the Generalized Algebraic Difference Approach (GADA) from the Hossfeld IV base model were fitted to predict site quality with both SI and SF. SF predictions were compared with SI regarding variability within the same plot and consistency in site quality predictions, using the observed maximum mean annual volume increment (MAI) as a direct measure of site quality. Results Both approaches showed good performance in model fitting and provided similar goodness-of-fit statistics and variability in the predictions. However, SI performed slightly stronger when related to MAI. Conclusion SF performed adequately in estimating site quality for even-aged P. radiata stands, with results comparable to those obtained using traditional SI.

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Building a dynamic growth model for trembling aspen in western Canada without age data

Canadian Journal of Forest Research ◽

10.1139/cjfr-2012-0366 ◽

2013 ◽

Vol 43 (3) ◽

pp. 256-265 ◽

Cited By ~ 13

Author(s):

Oscar García

Keyword(s):

Populus Tremuloides ◽

Site Occupancy ◽

Basal Area ◽

Site Index ◽

Growth And Yield ◽

Site Quality ◽

Diameter Distribution ◽

Stand Age ◽

Parameter Estimates ◽

Trembling Aspen

A biologically inspired whole-stand growth and yield model was developed for even-aged thinned or unthinned stands dominated by trembling aspen (Populus tremuloides Michx.). The estimation used permanent sample plot data from British Columbia, Alberta, Saskatchewan, and Manitoba, supplemented by published site index and young stand information. An ingrowth imputation procedure was devised to facilitate the use of plot measurements where small trees are not measured. Two published site index models were closely approximated by a simple age-base invariant equation. Good parameter estimates for mortality and basal area growth were obtained without using age observations, which were unreliable or missing. Four differential equations describe the dynamics of top height, trees per hectare, basal area, and a site occupancy factor. Current values of these variables are used to estimate total and merchantable volumes up to any diameter limit and diameter distribution parameters. When an independent source of site quality estimates is available, the final model does not require stand age knowledge for making growth and yield predictions.

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An Interim Economic Comparison of Thinning Treatments in a High Site Quality Red Pine Plantation

Northern Journal of Applied Forestry ◽

10.1093/njaf/5.3.211 ◽

1988 ◽

Vol 5 (3) ◽

pp. 211-215 ◽

Cited By ~ 1

Author(s):

Hal O. Liechty ◽

David D. Reed ◽

Glenn D. Mroz

Keyword(s):

Loblolly Pine ◽

Economic Value ◽

Site Index ◽

Red Pine ◽

Site Quality ◽

Stand Age ◽

Economic Returns ◽

Machine Productivity ◽

Current Product ◽

Harvesting Costs

Abstract Harvesting costs for seven thinning treatments applied to a highly productive (site index 81 at base age 50) red pine stand (age 22) were calculated using machine productivity rates developed for loblolly pine. The economic value of each treatment 10 years after the initial thinning was determined using the calculated harvesting costs and current product prices. Plots thinned to 60 ft2 ba/ac, 30% height, and 120 ft2 ba/ac treatments had the highest returns regardless of whether pulpwood or pulpwood and sawtimber markets were used to determine returns. The superior economic returns from the 30% and 120 ft2 treatments reflected the higher overall product yields from these thinning strategies. However, the 60 ft2 treatment, which had the second lowest merchantable cubic-foot yields in the study, had returns similar to the higher yielding treatments. This was due to: (1) larger early returns from the initial heavy thinnings in the 60 ft2 treatment, and (2) the decreased harvesting costs related to increased stand diameter growth of the heavier thinned treatment. North. J. Appl. For. 5:211-215, Sept. 1988.

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Yellow-Poplar Site Quality Related to Slope Type in Mountainous Terrain

Northern Journal of Applied Forestry ◽

10.1093/njaf/4.4.189 ◽

1987 ◽

Vol 4 (4) ◽

pp. 189-192 ◽

Cited By ~ 2

Author(s):

W. Henry McNab

Keyword(s):

Land Surface ◽

Appalachian Mountains ◽

Site Index ◽

Important Variable ◽

Surface Shape ◽

Site Quality ◽

Stand Age ◽

Mountainous Terrain ◽

Yellow Poplar ◽

Southern Appalachian

Abstract Site index and topographic variables were measured on 112, ¼-ac sample plots with yellow-poplar overstory in the Blue Ridge Province of the Southern Appalachian Mountains. The plots were grouped by slope type—nose, side, or head—and multiple regression analysis was used to develop equations for predicting height at 50 years. Estimated site index was significantly less on side slopes than on head slopes. Stand age was the most important variable in both equations, followed by aspect and land surface shape. The equations accounted for 79% of the variation of yellow-poplar height on head slopes and 84% on side slopes. North. J. Appl. For. 4:189-192, Dec. 1987.

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Mass and nutrient content of woody debris and forest floor in western red cedar and western hemlock forests on northern Vancouver Island

Canadian Journal of Forest Research ◽

10.1139/x93-134 ◽

1993 ◽

Vol 23 (6) ◽

pp. 1052-1059 ◽

Cited By ~ 58

Author(s):

Rodney J. Keenan ◽

Cindy E. Prescott ◽

J.P. Hamish Kimmins

Keyword(s):

Forest Floor ◽

Forest Type ◽

Woody Debris ◽

Nutrient Content ◽

Vancouver Island ◽

Western Hemlock ◽

N Availability ◽

Red Cedar ◽

The Mean ◽

Western Red Cedar

Biomass and C, N, P, and K contents of woody debris and the forest floor were surveyed in adjacent stands of old-growth western red cedar (Thujaplicata Donn)–western hemlock (Tsugaheterophylla (Raf.) Sarg.) (CH type), and 85-year-old, windstorm-derived, second-growth western hemlock–amabilis fir (Abiesamabilis (Dougl.) Forbes) (HA type) at three sites on northern Vancouver Island. Carbon concentrations were relatively constant across all detrital categories (mean = 556.8 mg/g); concentrations of N and P generally increased, and K generally decreased, with increasing degree of decomposition. The mean mass of woody debris was 363 Mg/ha in the CH and 226 Mg/ha in the HA type. The mean forest floor mass was 280 Mg/ha in the CH and 211 Mg/ha in the HA stands. Approximately 60% of the forest floor mass in each forest type was decaying wood. Dead woody material above and within the forest floor represented a significant store of biomass and nutrients in both forest types, containing 82% of the aboveground detrital biomass, 51–59% of the N, and 58–61% of the detrital P. Forest floors in the CH and HA types contained similar total quantities of N, suggesting that the lower N availability in CH forests is not caused by greater immobilization in detritus. The large accumulation of forest floor and woody debris in this region is attributed to slow decomposition in the cool, wet climate, high rates of detrital input following windstorms, and the large size and decay resistance of western red cedar boles.

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