Short-Term Impacts of Thinning Ponderosa Pine on Pandora Moth Densities, Pupal Weights, and Phenology

1995 ◽  
Vol 10 (3) ◽  
pp. 91-94
Author(s):  
Darrell W. Ross
Keyword(s):  
Pinus Ponderosa ◽  
Ponderosa Pine ◽  
Basal Area ◽  
Stand Density ◽  
Adult Emergence ◽  
Adult Density ◽  
Egg Hatch ◽  
Second Growth ◽  
Insect Phenology ◽  
Foliage Weight

Abstract Second-growth ponderosa pine (Pinus ponderosa) stands with outbreak populations of the pandora moth (Coloradia pandora) were thinned from below removing about half of the basal area. Thinning had no effect on pandora moth pupal density or weight, or emerging adult density in the following generation. However, adult emergence and egg hatch occurred 7-10 days earlier in thinned plots compared with unthinned plots. Egg and larval densities on a foliage weight basis were not significantly different between thinned and unthinned plots. Thinning stands infested with pandora moth will not significantly affect the course of an outbreak for at least one generation. Timing of direct controls for the pandora moth should consider the effect of stand density on insect phenology. West. J. Appl. For. 10(3):91-94.

Thinning ponderosa pine (Pinus ponderosa) stands reduces mortality while maintaining stand productivity

2013 ◽  
Vol 43 (4) ◽  
pp. 311-320 ◽  
Author(s):  
Jianwei Zhang ◽  
Martin W. Ritchie ◽  
Douglas A. Maguire ◽  
William W. Oliver
Keyword(s):  
Pinus Ponderosa ◽  
Ponderosa Pine ◽  
Bark Beetles ◽  
Basal Area ◽  
Stand Density ◽  
Growth Efficiency ◽  
Stand Age ◽  
Annual Increment ◽  
Stand Productivity ◽  
Residual Variation

We analyzed 45 years of data collected from three ponderosa pine (Pinus ponderosa Douglas ex P. Lawson & C. Lawson) levels-of-growing-stock installations in Oregon (OR) and northern California (CA), USA, to determine the effect of stand density regimes on stand productivity and mortality. We found that periodic annual increment (PAI) of diameter, basal area (BA), volume, and aboveground dry mass were significantly related to stand density index (SDI) and stand age at start of the period; the quadratic trends varied among sites. Precipitation departure from the normal for each period explained a significant amount of residual variation in all PAI variables except diameter. BA production did not change significantly as SDI exceeded 270 trees·ha−1 at the OR sites and 320 trees·ha−1 at the CA site. Stand productivity was the highest at Elliot Ranch (CA) and the least at Blue Mountains (OR). A similar trend held in growth efficiency under lower stand densities (SDI < 600). Most of the mortality was caused by Dendroctonus bark beetles in stands that exceeded SDI of 500 trees·ha−1. Limiting SDI was about 900 trees·ha−1, although plots at Elliot Ranch reached much higher than that. The results demonstrate that silvicultural control of stand density can be a powerful tool for reducing bark beetle caused mortality without sacrificing stand productivity.

scholarly journals Twenty-Five-Year Growth and Mortality of Planted Ponderosa Pine Repeatedly Thinned to Different Stand Densities in Northern California

1997 ◽  
Vol 12 (4) ◽  
pp. 122-130 ◽  
Author(s):  
William W. Oliver
Keyword(s):  
Sierra Nevada ◽  
Pinus Ponderosa ◽  
Ponderosa Pine ◽  
Bark Beetles ◽  
Basal Area ◽  
Stand Density ◽  
Northern California ◽  
Winter Storms ◽  
Randomized Design ◽  
Lower Site

Abstract A 20 yr old ponderosa pine (Pinus ponderosa var. ponderosa) plantation on a productive site on the west slope of the Sierra Nevada in northern California was thinned four times over a 25 yr period. Stand densities tested were Stand Density Indexes (SDI) of 73, 128, 183, 238, and 293 (equivalent to 40,70,100,130, and 160 ft2/ac of basal area), replicated three times in a randomized design. Growth was analyzed for each of five 5 yr periods. Periodic annual increments (PAI) of diameter, net basal area, and net total volume differed significantly among periods and, in the earlier periods, among stocking levels. Mortality from winter storms and bark beetles was largely confined to the higher stand densities and in periods 3 and 4 caused PAIs of net basal area and net total volume to decline below that of lower densities. The sensitivity of mortality to stand density suggests a thinning target of SDI 183 (about 100 ft²/ac of basal area) for similar stands—no higher than that recommended for eastside stands of much lower site productivity. This sensitivity coupled with rapid growth suggests that multiple thinnings will be necessary in similar stands to maintain healthy, vigorous trees. West. J. Appl. For. 12(4):122-130.

Vegetation responses to stand structure and prescribed fire in an interior ponderosa pine ecosystemThis article is one of a selection of papers from the Special Forum on Ecological Studies in Interior Ponderosa Pine — First Findings from Blacks Mountain Interdisciplinary Research.

2008 ◽  
Vol 38 (5) ◽  
pp. 909-918 ◽  
Author(s):  
Jianwei Zhang ◽  
Martin W. Ritchie ◽  
William W. Oliver
Keyword(s):  
Pinus Ponderosa ◽  
Prescribed Fire ◽  
Ponderosa Pine ◽  
Large Scale ◽  
Stand Structure ◽  
Basal Area ◽  
Stand Density ◽  
Structural Diversity ◽  
Ponderosa Pine Forest ◽  
Selection Of

A large-scale interior ponderosa pine ( Pinus ponderosa Dougl. ex P. & C. Laws.) study was conducted at the Blacks Mountain Experimental Forest in northeastern California. The primary purpose of the study was to determine the influence of structural diversity on the dynamics of interior pine forests at the landscape scale. High structural diversity (HiD) and low structural diversity (LoD) treatments were created with mechanical thinning on 12 main plots. Each plot was then split in half with one-half treated with prescribed fire. During the 5 year period after the treatments, the LoD treatments showed slightly higher periodic annual increments for basal area (BA) and significantly higher diameter increments than did the HiD treatments, although HiD carried twice as much BA as LoD did immediately after the treatments. Prescribed fire did not affect growth, but killed and (or) weakened some trees. No interaction between treatments was found for any variable. Stand density was reduced from the stands before treatments, but species composition did not change. Old dominant trees still grew and large snags were stable during the 5 year period. Treatments had minor impacts on shrub cover and numbers. These results suggest that ponderosa pine forest can be silviculturally treated to improve stand growth and health without sacrificing understory shrub diversity.

Long-Term Response of Planted Ponderosa Pine to Thinning in Oregon's Blue Mountains

1993 ◽  
Vol 8 (4) ◽  
pp. 126-132 ◽  
Author(s):  
P. H. Cochran ◽  
James W. Barrett
Keyword(s):  
Pinus Ponderosa ◽  
Ponderosa Pine ◽  
Mountain Pine Beetle ◽  
Volume Growth ◽  
Basal Area ◽  
Stand Density ◽  
Growth Potential ◽  
Average Height ◽  
Stand Density Index ◽  
John Day

Abstract A spacing study in ponderosa pine (Pinus ponderosa) was established in 1959 by thinning plots in a 33-yr-old plantation near John Day, Oregon. The influence of 4 spacings (17.2, 12.5, 10.1, and 8.7 ft) on stand and tree growth for a 31-yr period was examined. Study plots were remeasured five times after establishment. Periodic annual increments (PAI) of gross basal area, gross volume, and average height differed with period but not with spacing (P ≤ 0.10). The PAIs of mean diameter differed with period and decreased with increasing density. Annual height growth and annual gross and net growth of basal area and volume did not differ with spacing. Annual diameter growth was much greater for trees at the widest spacing. Annual volume growth of the largest 90 trees/ac was greatest at the widest spacing. Thirty-one years after thinning, the largest 90 trees/ac on the widest spacing had 73% of the volume of all the trees on the narrowest spacing. Mortality due to mountain pine beetle (Dendroctonus ponderosae) increased markedly when values for stand density index exceeded 200. Wide spacings increased average tree volumes, increased mean diameters, and reduced the probability of mortality without sacrificing gross cubic volume growth potential. West. J. Appl. For. 8(4):126-132.

Patterns of size variation over time in ponderosa pine stands established at different initial densities

2016 ◽  
Vol 46 (1) ◽  
pp. 101-113 ◽  
Author(s):  
Kathryn I. McGown ◽  
Kevin L. O’Hara ◽  
Andrew Youngblood
Keyword(s):  
Pinus Ponderosa ◽  
Ponderosa Pine ◽  
Size Variation ◽  
Basal Area ◽  
Stand Density ◽  
Absolute Size ◽  
Time Period ◽  
Symmetric Competition ◽  
Skewness Coefficient ◽  
Initial Spacing

We used six metrics of size and growth variation (standard deviation (SD), coefficient of variation (CV), skewness coefficient (S), Gini coefficient (G), Lorenz asymmetry coefficient (LAC), and growth dominance coefficient (GD)) to describe changes in two long-term ponderosa pine (Pinus ponderosa Douglas ex P. Lawson & C. Lawson) initial spacing trials in Oregon and Washington, USA. Trends were examined over a 35-year time period and across a range of initial stand densities (from 154 to 2470 trees·ha−1) for four measures of tree size: diameter at breast height (dbh, 1.37 m), basal area (BA), height, and volume. Unlike many previous studies of size variation in monospecific stands, our results suggest that variation declined or remained relatively stable for all treatments at both study areas. This suggests that these stands are experiencing size symmetric competition for belowground resources. We found that a combination of metrics is necessary to provide a complete picture of size variability and differentiation in developing stands. We recommend using the CV or G, as there were clear trends with increasing density for all size variables. If the objective of the assessment was to track changes in absolute size within an individual stand, we would recommend using the SD, as there were consistent trends with time for all size variables. S, LAC, and GD may be less suited for comparing differentiation during the early stages of stand development because of a lack of clear trends with stand density and time.

Forest Regrowth on the Cumberland Plateau and Implications for Productive Management

1983 ◽  
Vol 7 (4) ◽  
pp. 208-212 ◽  
Author(s):  
Robert N. Muller
Keyword(s):  
Species Composition ◽  
Basal Area ◽  
Stand Density ◽  
Cumberland Plateau ◽  
Old Growth ◽  
Nutrient Pools ◽  
Old Growth Forest ◽  
Composition And Structure ◽  
Second Growth ◽  
Commercial Species

Abstract An old-growth forest and a 35-year-old, second-growth forest on the Cumberland Plateau were studied to compare species composition and structure. Species composition and total basal area of the two stands did not differ, although total stand density was 19 percent lower and basal area of commercial species was 25 percent higher in the old-growth than in the second-growth stand. Analysis of size-class distributions showed that both stands were best represented by an inverse J-shaped distribution, which best describes old-age stands. The rapid regeneration of the second-growth stand seems to be the result of minimal disturbance to accumulated nutrient pools in the soil. The importance of these accumulated nutrient pools and implications for forest management on the Cumberland Plateau are discussed.

Corrigendum to: Assessing canopy fuel stratum characteristics in crown fire prone fuel types of western North America

2010 ◽  
Vol 19 (1) ◽  
pp. iii ◽  
Author(s):  
Miguel G. Cruz ◽  
Martin E. Alexander ◽  
Ronald H. Wakimoto
Keyword(s):  
Ponderosa Pine ◽  
Fire Management ◽  
Linear Regression Analysis ◽  
Basal Area ◽  
Stand Density ◽  
Fuel Load ◽  
Tree Level ◽  
Management Decision ◽  
Crown Fire ◽  
In Fire

Application of crown fire behavior models in fire management decision-making have been limited by the difficulty of quantitatively describing fuel complexes, specifically characteristics of the canopy fuel stratum. To estimate canopy fuel stratum characteristics of four broad fuel types found in the western United States and adjacent areas of Canada, namely Douglas-fir, ponderosa pine, mixed conifer, and lodgepole pine forest stands, data from the USDA Forest Service's Forest Inventory and Analysis (FIA) database were analysed and linked with tree-level foliage dry weight equations. Models to predict canopy base height (CBH), canopy fuel load (CFL) and canopy bulk density (CBD) were developed through linear regression analysis and using common stand descriptors (e.g. stand density, basal area, stand height) as explanatory variables. The models developed were fuel type specific and coefficients of determination ranged from 0.90 to 0.95 for CFL, between 0.84 and 0.92 for CBD and from 0.64 to 0.88 for CBH. Although not formally evaluated, the models seem to give a reasonable characterization of the canopy fuel stratum for use in fire management applications.

Stand density, drought, and herbivory constrain ponderosa pine regeneration pulse

2020 ◽  
Vol 50 (9) ◽  
pp. 862-871 ◽  
Author(s):  
Thomas E. Kolb ◽  
Kelsey Flathers ◽  
John B. Bradford ◽  
Caitlin Andrews ◽  
Lance A. Asherin ◽  
...  
Keyword(s):  
Pinus Ponderosa ◽  
Ponderosa Pine ◽  
Seedling Survival ◽  
Stand Density ◽  
Survival Duration ◽  
Northern Arizona ◽  
Growing Seasons ◽  
Pine Regeneration ◽  
Stand Thinning ◽  
Survival And Growth

Trees in dry forests often regenerate in episodic pulses when wet periods coincide with ample seed production. Factors leading to success or failure of regeneration pulses are poorly understood. We investigated the impacts of stand thinning on survival and growth of the 2013 cohort of ponderosa pine (Pinus ponderosa Douglas ex P. Lawson & C. Lawson) seedlings in northern Arizona, United States. We measured seedling survival and growth over the first five growing seasons after germination in six stand basal areas (BAs; 0, 7, 14, 23, 34, and 66 (unthinned) m2·ha−1) produced by long-term experimental thinnings. Five-year survival averaged 2.5% and varied among BAs. Mean survival duration was longer in intermediate BAs (11 to 16 months) than in clearings and high BAs (5 months). The BAs of 7, 14, and 23 m2·ha−1 had >2600 5-year-old seedlings·ha−1. In contrast, regeneration was lower in the clearing (666 seedlings·ha−1) and failed completely in the 34 m2·ha−1 and unthinned treatments. Seedling survival was highest during wet years and lowest during drought years. Many surviving seedlings had no net height growth between years 4 and 5 because of stem browsing. Results indicate that natural regeneration of ponderosa pine is influenced by stand BA, drought, herbivory, and interactions between extreme climatic events.

Intertree competition in uneven-aged ponderosa pine stands

2003 ◽  
Vol 33 (9) ◽  
pp. 1719-1726 ◽  
Author(s):  
C W Woodall ◽  
C E Fiedler ◽  
K S Milner
Keyword(s):  
Pinus Ponderosa ◽  
Ponderosa Pine ◽  
Basal Area ◽  
Growth Efficiency ◽  
Tree Size ◽  
Basal Area Increment ◽  
Diameter Class ◽  
Individual Tree ◽  
Sapwood Area ◽  
Competition Indices

Intertree competition indices and effects were examined in 14 uneven-aged ponderosa pine (Pinus ponderosa var. scopulorum Engelm.) stands in eastern Montana. Location, height, diameter at breast height (DBH), basal area increment, crown ratio, and sapwood area were determined for each tree (DBH >3.8 cm) on one stem-mapped plot (0.2-0.4 ha) in each sample stand. Based on tree locations, various competition indices were derived for each sample tree and correlated with its growth efficiency by diameter class. In addition, trends in individual tree attributes by diameter class and level of surrounding competition were determined. For trees with a DBH <10 cm, growth efficiency was most strongly correlated with the sum of surrounding tree heights within 10.6 m. The index most highly correlated for larger trees was the sum of surrounding basal area within 6.1 m. Regardless of tree size, individual tree growth efficiency, basal area increment, and crown ratio all decreased under increasing levels of competition, with the effect more pronounced in smaller trees. These results suggest that individual trees in uneven-aged stands experience competition from differing sources at varying scales based on their size, with response to competition diminishing as tree size increases.

scholarly journals Assessing canopy fuel stratum characteristics in crown fire prone fuel types of western North America

2003 ◽  
Vol 12 (1) ◽  
pp. 39 ◽  
Author(s):  
Miguel G. Cruz ◽  
Martin E. Alexander ◽  
Ronald H. Wakimoto
Keyword(s):  
Ponderosa Pine ◽  
Fire Management ◽  
Linear Regression Analysis ◽  
Basal Area ◽  
Stand Density ◽  
Fuel Load ◽  
Tree Level ◽  
Management Decision ◽  
Crown Fire ◽  
In Fire

Application of crown fire behavior models in fire management decision-making have been limited by the difficulty of quantitatively describing fuel complexes, specifically characteristics of the canopy fuel stratum. To estimate canopy fuel stratum characteristics of four broad fuel types found in the western United States and adjacent areas of Canada, namely Douglas-fir, ponderosa pine, mixed conifer, and lodgepole pine forest stands, data from the USDA Forest Service's Forest Inventory and Analysis (FIA) database were analysed and linked with tree-level foliage dry weight equations. Models to predict canopy base height (CBH), canopy fuel load (CFL) and canopy bulk density (CBD) were developed through linear regression analysis and using common stand descriptors (e.g. stand density, basal area, stand height) as explanatory variables. The models developed were fuel type specific and coefficients of determination ranged from 0.90 to 0.95 for CFL, between 0.84 and 0.92 for CBD and from 0.64 to 0.88 for CBH. Although not formally evaluated, the models seem to give a reasonable characterization of the canopy fuel stratum for use in fire management applications.

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