Hazard rating of lodgepole pine stands to mountain pine beetle outbreaks in southcentral Oregon

1984 ◽  
Vol 14 (5) ◽  
pp. 666-671 ◽  
Author(s):  
John David Stuart
Keyword(s):  
Mountain Pine Beetle ◽  
Stand Structure ◽  
Stand Density ◽  
Stepwise Discriminant Analysis ◽  
Growth Ratio ◽  
South Central ◽  
Periodic Growth ◽  
Quadratic Mean Diameter ◽  
Stand Density Index ◽  
Hazard Rating

Stand structure and vigor variables were used to develop a model for predicting the development of a Dendroctonusponderosae Hopk. outbreak in climax Pinuscontorta Dougl. ex Loud. var. murrayana Grev. and Balf. stands in south central Oregon. Stepwise discriminant analysis indicated the significant predictor variables were quadratic mean diameter and the number of rings in the outermost centimetre of radial growth at breast height (p = 0.00001, canonical correlation coefficient = 0.77235). Ninety-three percent of the stands were correctly classified into their appropriate groups (attacked versus unattacked). None of the five indices of competition tested (i) Waring and Pitman's tree vigor index, (ii) Mahoney's periodic growth ratio, (iii) Krajicek's crown competition factor, (iv) Hegyi's competition index, and (v) Curtis's stand density index) were significant discriminators.

scholarly journals Effect of Diameter Limits and Stand Structure on Relative Density Indices: A Case Study

2010 ◽  
Vol 25 (4) ◽  
pp. 169-175 ◽  
Author(s):  
Robert O. Curtis
Keyword(s):  
Relative Density ◽  
Stand Structure ◽  
Stand Density ◽  
Aged Condition ◽  
Shade Tolerant Species ◽  
Density Indices ◽  
Quadratic Mean Diameter ◽  
Stand Density Index ◽  
Definition Of

Abstract An understory of shade-tolerant species often develops in stands in the Douglas-fir region of western Washington and Oregon and can have a disproportionate effect on relative density indices, such as Reineke stand density index and Curtis relative density. The effects of such understories and of other departures from the even-aged condition are illustrated with selected stand data. In general, the summation methods are less influenced by departures from the even-aged condition than are the conventional calculations based on quadratic mean diameter. Recommendations are made for consistent definition of the lower diameter limit of trees to be included in such computations

The applicability of available hazard rating systems for mountain pine beetle in lodgepole pine stands of southeastern Wyoming

1986 ◽  
Vol 16 (2) ◽  
pp. 222-225 ◽  
Author(s):  
Steven A. Katovich ◽  
Robert J. Lavigne
Keyword(s):  
Mountain Pine Beetle ◽  
The United States ◽  
Rating Systems ◽  
Growth Ratio ◽  
Diameter At Breast Height ◽  
Medicine Bow Mountains ◽  
Breast Height ◽  
Periodic Growth ◽  
Hazard Rating ◽  
Hazard Rating Systems

Five hazard rating systems for Dendroctonusponderosae Hopkins in Pinuscontorta Dougl. stands were compared under nonoutbreak conditions in the Medicine Bow Mountains of southeastern Wyoming. The applicability of these systems, which were designed in other regions of the United States, to P. contorta stands in southeastern Wyoming was investigated. Thirty-two stands in four different age and diameter categories were sampled and rated by each system. Diameter at breast height did not correlate well with phloem width in any of the stands, as implied by the system of Amman and co-workers. A direct phloem width measurement could further refine this system. Periodic growth ratio, used in both the Berryman and Mahoney systems, did not differentiate between fast- and slow-growing trees. Crown competition factor did not positively correlate with increasing diameter at breast height, as implied by the system of Schenk and co-workers. Stand production ranged from 11.1 to 51.0 g wood•m leaf area−2•year−1, applying a modified system based on that designed by Mitchell and co-workers, indicating very high risk in every stand sampled. Further development and validation of hazard rating systems is necessary for improved analysis of risk to P. contorta stands from D. ponderosae in this region.

Lodgepole pine regeneration in an old, self-perpetuating forest in south central Oregon

1989 ◽  
Vol 19 (9) ◽  
pp. 1096-1104 ◽  
Author(s):  
John D. Stuart ◽  
James K. Agee ◽  
Robert I. Gara
Keyword(s):  
Sierra Nevada ◽  
Mountain Pine Beetle ◽  
Stand Structure ◽  
Lodgepole Pine ◽  
Disturbance Intensity ◽  
South Central ◽  
Mountain Pine ◽  
Pine Regeneration ◽  
Pine Beetle ◽  
Type Frequency

Historic regeneration patterns and regeneration requirements were investigated in an old, self-regenerating lodgepole pine (Pinusconforta Dougl. ssp. murrayana (Balf.) Critchfield) forest in south central Oregon. The forest was multiaged, with episodic regeneration pulses being correlated with mountain pine beetle (Dendroctonusponderosae Hopk.) outbreaks or fire. The magnitude of a regeneration pulse was a function of disturbance intensity. Tree ring indices show growth declines prior to mountain pine beetle outbreaks. Radial tree growth improved following disturbance. Differences in stand structure among climax lodgepole pine stands in the Rocky Mountains, Sierra Nevada, and south central Oregon were related to disturbance type, frequency, and intensity. Successful lodgepole pine reproduction was limited by soil moisture and partly by microclimate. Shading did not inhibit seedling establishment, but rather provided relief from excessive evapotranspiration, heat, and frost.

Growth characteristics of lodgepole pine associated with the start of mountain pine beetle outbreaks

1983 ◽  
Vol 13 (1) ◽  
pp. 137-144 ◽  
Author(s):  
D. M. Shrimpton ◽  
A. J. Thomson
Keyword(s):  
Tree Growth ◽  
Mountain Pine Beetle ◽  
Cost Effective ◽  
Annual Increment ◽  
Growth Ratio ◽  
Stand Growth ◽  
Mountain Pine ◽  
Periodic Growth ◽  
Pine Beetle ◽  
Mean Annual Increment

The dynamics of tree and stand growth were studied in six small but expanding mountain pine beetle outbreaks in British Columbia. Stands had exceeded a previously reported hazard threshold of age 80 years by 26 years, and a second frequently used hazard threshold of 20.5 cm mean dbh was exceeded by 37 years. However, stands had exceeded maturity, as defined by the intersection of current annual increment (CAI) and mean annual increment (MAI), by an average of only 17 years. In all cases, the beginnings of the outbreaks were coincident with a period of reduced tree growth. This reduced tree growth was difficult to detect at breast height, with a consequent failure of the periodic growth ratio to indicate susceptibility. Although the stands were past the point of maturity, the dominant and codominant trees continued to add significant wood volume, which could make surveillance for incipient outbreaks and subsequent control actions cost effective.

Influence of topography and forest structure on patterns of mixed severity fire in ponderosa pine forests of the South Dakota Black Hills, USA

2006 ◽  
Vol 15 (4) ◽  
pp. 557 ◽  
Author(s):  
Leigh B. Lentile ◽  
Frederick W. Smith ◽  
Wayne D. Shepperd
Keyword(s):  
South Dakota ◽  
Ponderosa Pine ◽  
Stand Structure ◽  
Stand Density ◽  
Fire Effects ◽  
Black Hills ◽  
Burn Severity ◽  
High Severity ◽  
Density Index ◽  
Stand Density Index

We examined the influence of topography and stand structure on fire effects within the perimeter of the ~34 000 ha Jasper fire of 2000 in ponderosa pine (Pinus ponderosa Laws.) forests of the South Dakota Black Hills, USA. We used a remotely sensed and field-verified map of post-fire burn severity (accuracy 69%, kappa statistic 0.54), the Digital Elevation Model, and vegetation databases maintained by the Black Hills National Forest to empirically test relationships at 500 randomly located points in each of three severity classes. Burn severity was defined as the relative degree of post-fire change based on fire effects on soil, forest floor, and vegetation. This fire burned rapidly, yet created a patchy mosaic of effects (25, 48, and 27% low, moderate, and high severity). Stands burned by low and moderate severity fire had fewer trees (stand density index <470 with fewer than 230 trees >13 cm diameter at breast height ha–1) and were found on less steep sites (slope < 18%). Denser stands (stand density index >470) with larger trees (average stand diameter >24 cm) or many small trees were more likely to burn with high severity effects. Our results suggest that managers should consider topography and stand structure together when making strategic decisions about which stands to thin or otherwise manage to reduce the severity with which forests will burn in wildfires.

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.

Susceptibility of lodgepole pine to infestation by mountain pine beetles following partial cutting of stands

1988 ◽  
Vol 18 (6) ◽  
pp. 688-695 ◽  
Author(s):  
Gene D. Amman ◽  
Mark D. McGregor ◽  
Richard F. Schmitz ◽  
Robert D. Oakes
Keyword(s):  
Growth Response ◽  
Mountain Pine Beetle ◽  
Lodgepole Pine ◽  
Partial Cutting ◽  
Poor Growth ◽  
Growth Ratio ◽  
Mountain Pine ◽  
Periodic Growth ◽  
Pine Beetle ◽  
Pine Stands

Thinning stands of lodgepole pine (Pinuscontorta Douglas var. latifolia Engelmann) is thought to increase vigor and thereby reduce susceptibility to mountain pine beetle (Dendroctonusponderosae Hopkins). Partial cut stands of lodgepole in the Kootenai and Lolo National forests, Montana, U.S.A., provided opportunity (i) to determine growth response of 76- to 102-year-old lodgepole pines following thinning and (ii) to test the hypothesis that vigor of residual trees infested and uninfested by beetles does not differ. Lodgepole pine stands receiving different partial cutting prescriptions were sampled. Characteristics measured for trees within the sample were diameter at breast height, grams of stem wood per square metre of foliage, periodic growth ratio, and leaf area. Trees in most treatments showed decreased growth the 1st year following thinning. The 1st year was followed by increased growth during the next 4 years. Of the tree characteristics measured, only dbh was significantly different on both forests between live trees and trees killed by the mountain pine beetle; the latter were larger (P < 0.001). The low amount of mountain pine beetle infestation in all stands in the presence of poor growth response and vigor of residual trees suggests that factors other than tree vigor will regulate mountain pine beetle infestations in recently thinned lodgepole pine stands. We hypothesize change in stand microclimate is the principal factor.

scholarly journals Effect of structure and dynamics of forests on the occurrence of Erythronium dens-canis

2020 ◽  
Vol 66 (No. 9) ◽  
pp. 349-360
Author(s):  
Stanislav Vacek ◽  
Rostislav Linda ◽  
Ivo Králíček ◽  
Karel Vančura ◽  
Anna Prokůpková ◽  
...  
Keyword(s):  
Stand Structure ◽  
Basal Area ◽  
Stand Density ◽  
European Beech ◽  
Forest Stand ◽  
Beech Forests ◽  
Spruce Forests ◽  
Forest Stand Structure ◽  
Stand Density Index ◽  
The Impact

The paper presents the results of a study on the impact of forest stand structure and development in 1998 to 2018 on the occurrence of dog’s tooth violets (Erythronium dens-canis L.) in the Medník National Nature Monument, Czech Republic. The research was carried out in mixed European hornbeam and sessile oak stands, herb-rich European beech stands and the Sázava-river Norway spruce ecotype stands. The site and stand characteristics of the following three forest stand types were compared: 1) oak-hornbeam forests, 2) herb-rich beech forests and 3) secondary spruce forests. The results showed that the ratio of sterile and fertile plants was 2.9 to 1. The occurrence of E. dens-canis was higher in older stands with differentiated structure. On the contrary, stands characterized by a higher number of trees and basal area negatively affected the population size of E. dens‑canis. Significantly, the density of E. dens-canis decreased with increasing stand density index (SDI) and increased with increasing diameter differentiation index in relation to tree neighbours (TM<sub>d</sub>). During the period of 20 years, the E. dens-canis population increased by 40.4% on permanent research plots, while the highest changes were observed on spruce plots (+92.1%) and the lowest increase was in oak-hornbeam forests (+18.0%). The highest numbers of E. dens-canis plants were found in herb-rich beech forests (1 774 plants·ha<sup>–1</sup>), lower numbers occurred in oak-hornbeam forests (784 plants·ha<sup>–1</sup>) and minimal in secondary spruce forests (51 plants·ha<sup>–1</sup>). <br /><br />

Forest structure altered by mountain pine beetle outbreaks affects subsequent attack in a Wyoming lodgepole pine forest, USA

2011 ◽  
Vol 41 (12) ◽  
pp. 2403-2412 ◽  
Author(s):  
Daniel M. Kashian ◽  
Rebecca M. Jackson ◽  
Heather D. Lyons
Keyword(s):  
Pinus Contorta ◽  
Mountain Pine Beetle ◽  
Stand Structure ◽  
Lodgepole Pine ◽  
Climate Change Scenarios ◽  
Cone Production ◽  
Mountain Pine ◽  
Large Trees ◽  
Pine Beetle ◽  
The 1960S

Extensive outbreaks of the mountain pine beetle ( Dendroctonus ponderosae Hopkins) will alter the structure of many stands that will likely be attacked again before experiencing a stand-replacing fire. We examined a stand of lodgepole pine ( Pinus contorta var. latifolia Engelm. ex S. Watson) in Grand Teton National Park currently experiencing a moderate-level outbreak and previously attacked by mountain pine beetle in the 1960s. Consistent with published studies, tree diameter was the main predictor of beetle attack on a given tree, large trees were preferentially attacked, and tree vigor, age, and cone production were unimportant variables for beetle attack at epidemic levels. Small trees killed in the stand were killed based mainly on their proximity to large trees and were likely spatially aggregated with large trees as a result of the previous outbreak. We concluded that the driving factors of beetle attack and their spatial patterns are consistent across outbreak severities but that stand structure altered by the previous outbreak had implications for the current outbreaks in the same location. This study should catalyze additional research that examines how beetle-altered stand structure affects future outbreaks — an important priority for predicting their impacts under climate change scenarios that project increases in outbreak frequency and extent.

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