Crown shyness in lodgepole pine stands of varying stand height, density, and site index in the upper foothills of Alberta

2006 ◽  
Vol 36 (9) ◽  
pp. 2104-2111 ◽  
Author(s):  
Heather Fish ◽  
Victor J Lieffers ◽  
Uldis Silins ◽  
Ronald J Hall
Keyword(s):  
Relative Density ◽  
Light Transmission ◽  
Lodgepole Pine ◽  
Empty Space ◽  
Site Index ◽  
Canopy Closure ◽  
Site Factors ◽  
Crown Length ◽  
Stand Height ◽  
Crown Shyness

Crown shyness is the empty space between crowns in fully stocked stands that is not related to tree-fall gaps. The objectives of this study were to determine the stand and site factors that control crown shyness in lodgepole pine (Pinus contorta Dougl. ex Loud.) stands and to evaluate whether stands experiencing crown shyness compensate for leaf area losses by maintaining longer crowns. We measured canopy closure (i.e., the inverse of crown shyness), crown radius and length, and green litterfall in stands of various height, relative density, and site index. Canopy closure decreased with stand height and increased with site index and relative density. Green litterfall increased with height and relative density. Crown radius and crown length reached a plateau by 8-10 m height, despite increased spacing between tree boles with increasing stand height. Crown radius increased with height and site index but declined with relative density and slenderness coefficient. Crown length also increased with height and site index but declined with slenderness coefficient. Despite the fact that, in tall stands, where >50% of the sky was not covered by crowns, there was not an accompanying increase in crown length to take advantage of the apparent increase in light transmission to the lower crown.

Tree form and taper variation over time for interior lodgepole pine

1994 ◽  
Vol 24 (9) ◽  
pp. 1904-1913 ◽  
Author(s):  
Charles K. Muhairwe
Keyword(s):  
Lodgepole Pine ◽  
Stand Density ◽  
Tree Height ◽  
Analysis Data ◽  
Site Factors ◽  
Tree Shape ◽  
Tree Form ◽  
Crown Length ◽  
Quadratic Mean Diameter ◽  
Over Time

Changes in tree form and taper over time, as affected by changes in tree, stand, and site factors for interior lodgepole pine (Pinuscontorta var. latifolia Engelm.) were investigated using detailed stem analysis data from interior British Columbia. It was found that tree shape and taper change along the stem at one time and over time with changes in tree and stand factors, particularly the diameter at breast height to total tree height ratio, crown length, and crown ratio, and with predicted quadratic mean diameter at age 50 years, a stand density measure. At young ages, the trees were parabolic in shape from ground to top. However, as they increased in size over time, different portions of the stem took different shapes because of unequal growth in diameter along the stem. Changes in tree shape and taper over time were closely related to the crown size, which is related to stand density.

scholarly journals Inconsistent Growth Response to Fertilization and Thinning of Lodgepole Pine in the Rocky Mountain Foothills Is Linked to Site Index

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Bradley D. Pinno ◽  
Victor J. Lieffers ◽  
Simon M. Landhäusser
Keyword(s):  
Pinus Contorta ◽  
Growth Response ◽  
Lodgepole Pine ◽  
Rocky Mountain ◽  
Site Index ◽  
Basic Site ◽  
Nutrient Concentrations ◽  
Diameter Growth ◽  
Growth Responses ◽  
Site Factors

Fertilization of conifers often results in highly variable growth responses across sites which are difficult to predict. The goal of this study was to predict the growth response of lodgepole pine (Pinus contorta var. latifolia) crop trees to thinning and fertilization using basic site and foliar characteristics. Fifteen harvest-origin stands along the foothills of the Rocky Mountains of Alberta were subjected to six treatments including two levels of thinning (thinning to 2500 stems per hectare and a control) and three types of fertilization (nitrogen-only fertilization, complete fertilization including nitrogen with added P, K, S, Mg, and B, and no fertilization). After three growing seasons, the growth response and foliar status of the crop trees were examined and this response was related to site and foliar characteristics. There was a small and highly variable additive response to fertilization and thinning; diameter growth of crop trees increased relative to the controls an average of 0.3 cm with thinning, 0.3 cm with either N-only or complete fertilization and 0.6 cm when thinned and fertilized. The increase in diameter growth with thinning and nitrogen-only fertilization was positively related to site index but not to any other site factors or pretreatment foliar variables such as nutrient concentrations, ratios, or thresholds.

A Multipoint Felled-Tree Validation of Height–Age Modeled Growth Rates

2020 ◽  
Vol 66 (3) ◽  
pp. 275-283 ◽  
Author(s):  
Halli Hemingway ◽  
Mark Kimsey
Keyword(s):  
Growth Rates ◽  
Rocky Mountain ◽  
Site Index ◽  
Douglas Fir ◽  
Alternative Methods ◽  
Forest Site ◽  
Site Productivity ◽  
Site Factors ◽  
Forest Management Planning ◽  
Breast Height

Abstract Accurate measures of forest site productivity are essential for forest-management planning. The most common measure of site productivity is breast height–age site index (BHASI)—the expected height at a reference age. Error from including early growth in productivity estimates and limited applicability of any one BHASI model warrant development of alternative methods. Exploring alternatives may only be necessary if regional BHASI models are not accurately predicting growth rates. We compared modeled height growth rates for Rocky Mountain Douglas-fir (Pseudotsuga menziesii var. glauca) to felled-tree measurements to evaluate relative performance of a regional BHASI model. An orthogonal sampling design ensured samples were collected across a range of site factors known to influence Douglas-fir growth rates. Growth rates for each 10 m section were calculated and compared to BHASI modeled growth rates. The regional BHASI model underpredicted growth rates from breast height to 30 m. Observed growth rates from 10 to 30 m accounted for the majority of underprediction relative to BHASI modeled growth rates. An alternative multipoint method of defining site productivity is described. More research comparing BHASI and alternative methods is needed, given the growth rate error associated with one-point site productivity assessment.

scholarly journals Early Height Growth and Site Index of Lodgepole Pine Under Wet and Dry Soil Moisture Regimes in British Columbia

1997 ◽  
Vol 12 (1) ◽  
pp. 5-8
Author(s):  
Gordon D. Nigh
Keyword(s):  
Soil Moisture ◽  
Pinus Contorta ◽  
Lodgepole Pine ◽  
Site Index ◽  
Height Growth ◽  
Moisture Regimes ◽  
Indicator Variables ◽  
Soil Moisture Availability ◽  
A Site ◽  
Growth Intercept

Abstract The objective of this study was to determine whether the relationship between site index and early height growth of lodgepole pine (Pinus contorta var. latifolia) is the same on wet and dry sites. If the height growth/site index relationship is the same for different site types, then only one growth intercept model is required to estimate site index. Indicator variables in nonlinear regression were used to incorporate soil moisture availability into a growth intercept model. One set of parameters in a site index/early height growth model was adequate for both wet and dry sites. This result was supported graphically. Therefore, only one growth intercept model is necessary for the sites examined in this study. West. J. Appl. For. 12(1):5-8.

Stand growth responses after fertilization for thinned lodgepole pine, Douglas-fir, and spruce in forests of interior British Columbia, Canada

2019 ◽  
Vol 49 (11) ◽  
pp. 1471-1482
Author(s):  
Woongsoon Jang ◽  
Bianca N.I. Eskelson ◽  
Louise de Montigny ◽  
Catherine A. Bealle Statland ◽  
Derek F. Sattler ◽  
...  
Keyword(s):  
British Columbia ◽  
Picea Glauca ◽  
Lodgepole Pine ◽  
Basal Area ◽  
Stand Density ◽  
Site Index ◽  
Douglas Fir ◽  
Picea Sitchensis ◽  
Growth And Yield ◽  
Growth Responses

This study was conducted to quantify growth responses of three major commercial conifer species (lodgepole pine (Pinus contorta Douglas ex Loudon var. latifolia Engelm. ex S. Watson), interior Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. glauca (Beissn.) Franco), and spruce (white spruce (Picea glauca (Moench) Voss) and hybrid spruce (Picea engelmannii Parry ex. Engelm. × Picea glauca (Moench) Voss × Picea sitchensis (Bong.) Carrière))) to various fertilizer blends in interior British Columbia, Canada. Over 25 years, growth-response data were repeatedly collected across 46 installations. The fertilizer blends were classified into three groups: nitrogen only; nitrogen and sulfur combined; and nitrogen, sulfur, and boron combined. The growth responses for stand volume, basal area, and top height were calculated through absolute and relative growth rate ratios relative to a controlled group. Fertilizer blend, inverse years since fertilization, site index, stand density at fertilization, and their interactions with the fertilizer blend were used as explanatory variables. The magnitude and significance of volume and basal area growth responses to fertilization differed by species, fertilizer-blend groups, and stand-condition variables (i.e., site index and stand density). In contrast, the response in top height growth did not differ among fertilization blends, with the exception of the nitrogen and sulfur fertilizer subgroup for lodgepole pine. The models developed in this study will be incorporated into the current growth and yield fertilization module (i.e., Table Interpolation Program for Stand Yields (TIPSY)), thereby supporting guidance of fertilization applications in interior forests in British Columbia.

Influence of Site Factors on Incidence of Vole and Lemming Feeding Damage to Forest Plantations

1991 ◽  
Vol 6 (3) ◽  
pp. 64-67 ◽  
Author(s):  
Thomas P. Sullivan ◽  
Wayne L. Martin
Keyword(s):  
Picea Glauca ◽  
Pinus Contorta ◽  
Forest Type ◽  
Lodgepole Pine ◽  
Seedling Survival ◽  
Meadow Vole ◽  
Abies Lasiocarpa ◽  
Feeding Damage ◽  
Site Factors ◽  
Average Survival

Abstract The incidence of meadow vole (Microtus pennsylvanicus) and brown lemming (Lemmus sibiricus) feeding damage to young plantations of lodgepole pine (Pinus contorta var. latifolia) and interior spruce (Picea glauca × Picea engelmannii) was studied in west-central British Columbia. Fifty-eight plantations were surveyed for seedling survival and stocking, and an additional 21 older plantations of lodgepole pine were surveyed for tree damage. Average survival of pine (47.7%) was significantly lower than that of spruce (56.0%). Because of mortality from vole feeding, 24 of the 58 plantations were not satisfactorily restocked. Planted trees were attacked significantly more than natural regeneration. Severely attacked plantations occurred in the spruce-subalpine fir (Abies lasiocarpa) forest type at elevations > 800 m on N to NE aspects. Susceptible plantations generally had mechanical or no site preparation with complex post-harvest debris and limited vegetation cover. West. J. Appl. For. 6(3):64-67.

A Lodgepole Pine Density Management Diagram

1986 ◽  
Vol 1 (1) ◽  
pp. 6-11 ◽  
Author(s):  
James B. McCarter ◽  
James N. Long
Keyword(s):  
Pinus Contorta ◽  
Lodgepole Pine ◽  
Site Index ◽  
Management Regimes

Abstract A diagram is presented that can greatly facilitate density management of lodgepole pine (Pinus contorta) stands. Together with site index tables or curves, the diagram can be used to estimate average tree sizes and total yields produced under various density management regimes. Its use is illustrated with three alternative regimes. West. J. Appl. For. 1:6-11, Jan. 1986

scholarly journals Height Growth Pattern of Lodgepole Pine in Relation to Natural Subregions in Alberta

2004 ◽  
Vol 19 (3) ◽  
pp. 154-159 ◽  
Author(s):  
G. Geoff Wang ◽  
Shongming Huang ◽  
David J. Morgan
Keyword(s):  
Growth Pattern ◽  
Lodgepole Pine ◽  
Quantitative Measure ◽  
Site Index ◽  
Height Growth ◽  
Growth Patterns ◽  
Volume Estimation ◽  
The Other ◽  
Breast Height ◽  
Variable Site

Abstract Based on the provincial stem analysis and permanent sample plot (PSP) data of 1,580 felled dominant and codominant trees, height growth patterns of lodgepole pine were compared among the three major natural subregions [Sub-Alpine (SAL), Upper Foothills (UFH), and Lower Foothills (LFH)] in Alberta. The comparison used the ratio of heights at 70 and 30 years of breast height age (Z ratio) as a quantitative measure of height growth pattern (i.e., the response variable), site index (height at breast height age of 50 years) as the covariate, and natural subregion as the factor. Results indicated that: (1) the height growth pattern in the SAL natural subregion was significantly different from other natural subregions; and (2) no significant differences in height growth pattern were found between other natural subregions. Two polymorphic height and site index curves were developed: one for the SAL natural subregion and the other for the UFH and LFH natural subregions. Comparisons between the two curves and the previously developed provincial curve indicated that, for the same site index, trees in the SAL subregion grow consistently slower after 50 years. When the provincial height and site index curve was applied to the SAL natural subregion, large differences (≤14%) in gross volume estimation were found. However, volume estimation differences were very small (<2%) when the provincial curve was applied to the other two natural subregions. It is recommended that the natural subregion-based curves should be used for predicting lodgepole pine site index or height at any age in the SAL natural subregion. West. J. Appl. For. 19(3):154–159.

Circumferential variation in the relative density of lodgepole pine

1989 ◽  
Vol 19 (2) ◽  
pp. 276-279
Author(s):  
Josefina S. Gonzalez
Keyword(s):  
Relative Density ◽  
Present Method ◽  
Lodgepole Pine ◽  
Breast Height ◽  
Two Samples ◽  
The Mean

The circumferential variation in the wood relative density of lodgepole pine (Pinuscontorta var. latifolia Engelm.) was examined in eight discs taken at breast height. The purpose was to determine if the present method of analyzing two opposite radial strips from pith to bark was sufficient for estimating the mean density of the disc. Results showed that two samples taken opposite each other would give comparable or better approximation of the mean density of the disc than would three or four samples taken at random.

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