scholarly journals Variability in sub-regional impacts of dwarf mistletoe on mature lodgepole pine

1997 ◽  
Vol 73 (3) ◽  
pp. 371-375 ◽  
Author(s):  
Alan J. Thomson ◽  
John A. Muir ◽  
Kathy J. Lewis
Keyword(s):  
Forest Inventory ◽  
Lodgepole Pine ◽  
Stand Density ◽  
Dwarf Mistletoe ◽  
Clear Cut ◽  
Regional Impacts ◽  
Forest Practices ◽  
Roadside Survey ◽  
Pine Stands ◽  
Old Trees

Impact of lodgepole pine dwarf mistletoe was determined in six sub-areas of Forest Inventory Zone H, near Prince George, British Columbia, using a roadside survey and measurements of mature infected trees. Mistletoe effects on DBH were evident only in two of the sub-areas surveyed (Westlake and Nechako). After correcting DBH measurements for competition (stand density), dbh of 100–120 year old and 121–150 year old trees was reduced 10% and 17% respectively, in the highest mistletoe rating (DMR) category (4.5–6.0). Height/DBH relationships were affected by dwarf mistletoe only in the Nechako area. Mistletoe effects in the Nechako and Westlake areas, in stands older than 120 years with mistletoe ratings of 4.5–6.0, resulted in volume reductions of 28–42%, depending on the effects of mistletoe on height. Further losses might accrue in lodgepole pine stands if clear-cut harvesting were restricted by the BC Forest Practices Code, unless infected stems are selectively removed. Key words: roadside survey, dwarf mistletoe rating (DMR), Forest Practices Code

The effects of dwarf mistletoe, witches' brooms, stand structure, and site characteristics on the crown architecture of lodgepole pine in Oregon

2002 ◽  
Vol 32 (8) ◽  
pp. 1360-1371 ◽  
Author(s):  
R C Godfree ◽  
R O Tinnin ◽  
R B Forbes
Keyword(s):  
Pinus Ponderosa ◽  
Ponderosa Pine ◽  
Soil Type ◽  
Pinus Contorta ◽  
Stand Structure ◽  
Lodgepole Pine ◽  
Stand Density ◽  
Dwarf Mistletoe ◽  
Site Characteristics ◽  
Crown Dimensions

We investigated the importance of lodgepole pine dwarf mistletoe (Arceuthobium americanum Nutt.) in determining the height to crown top (HCT), height to crown base (HCB), and live crown ratio (LCR) of 2025 lodgepole pine (Pinus contorta var. murrayana (Grev. & Balf.) Engelm.) growing over a 24-km2 study site in central Oregon. We compared the effects of infection and associated witches' brooms with those of site topography, soil type, shrub cover, stand density, and the abundance of mature ponderosa pine (Pinus ponderosa Dougl. ex P. Laws. & C. Laws). using multiple regression and path analysis. The density of dominant-size P. contorta was consistently the most important factor influencing HCT, HCB, and LCR across the study site. In dense stands, trees tended to have elevated crown bases due to self-pruning and, hence, lower values of LCR. Dwarf mistletoe and related witches' brooms uniquely explained 6.9% of the variance in LCR, which was close to that of dominant P. contorta (7.1%) and more than that of soil type (3.0%), but explained only 2.6% of the variance in HCB, which was less than that of dominant P. contorta (6.5%) and soil type (4.6%). Regression models suggest that heavily infected trees should be 18% shorter and have crown bases 37% lower than uninfected trees, while moderately infected trees should have an LCR over 20% larger than that of uninfected and heavily infected trees. We also found that the largest 25 heavily infected trees sampled were approximately 19% shorter and 11–13% smaller in diameter than the largest 25 uninfected trees. The results suggest that dwarf mistletoe can be an important factor in determining the crown dimensions of P. contorta but that these effects may be interpreted only in the context of site characteristics and stand structure.

Estimation of foliage area in dense Montana lodgepole pine stands

1987 ◽  
Vol 17 (4) ◽  
pp. 320-324 ◽  
Author(s):  
Roger D. Hungerford
Keyword(s):  
Lodgepole Pine ◽  
Basal Area ◽  
Stand Density ◽  
Tree Height ◽  
Area Ratio ◽  
Density Range ◽  
Sapwood Area ◽  
Crown Length ◽  
Pine Stands

Six stands of lodgepole pine, Pinuscontorta ssp. latifolia (Engelm.) Critchfield, in Montana were sampled to evaluate sapwood area (at 1.37 m and the crown base), basal area (at 1.37 m), tree height, and crown length as predictors of foliage area. Densities of the six stands ranged from 2900 to 17 800 stems/ha. This density range was picked to determine how stand density affects the ratio of foliage area to basal sapwood area. Regression estimates of foliage area using basal area and sapwood area at 1.37 m and the crown base were equally good. Within the sampled range of stand densities, differences in the foliage area to sapwood area ratio were not significant. The amount of foliage area served per unit of sapwood area (at 1.37 m) averaged 0.25 m2/cm2 for all 54 trees sampled. This value of foliage area per unit of sapwood area in dense stands was smaller than most other published values.

scholarly journals Technical Commentary: Management of Lodgepole Pine Stand Density to Reduce Susceptibility to Mountain Pine Beetle Attack

1996 ◽  
Vol 11 (2) ◽  
pp. 50-53 ◽  
Author(s):  
J. A. Anhold ◽  
M. J. Jenkins ◽  
J. N. Long
Keyword(s):  
Relative Density ◽  
Mountain Pine Beetle ◽  
Tree Mortality ◽  
Lodgepole Pine ◽  
Stand Density ◽  
Threshold Level ◽  
Management Regime ◽  
Mountain Pine ◽  
Pine Beetle ◽  
Pine Stands

Abstract Silvicultural strategies to reduce tree losses from mountain pine beetle attacks typically seek to reduce relative densities in order to increase tree resistance and thus lower potential beetle attacks. For lodgepole pine stands, however, the tree mortality/relative density relationship is nonlinear. We describe three relative density zones corresponding to different levels of resistance to beetle attack. In the density management of young lodgepole pine stands, we propose two alternative strategies to reduce future losses from mountain pine beetle attacks. The first density management regime involves a low density (i.e., SDI < 140) throughout the rotation. The second density management regime is designed to maintain relative density above a threshold level (i.e., SDI > 245). West. J. Appl. For. 11(2):50-53.

scholarly journals The effects of stand characteristics on reindeer lichens and range use by semi-domesticated reindeer

Rangifer ◽  
1990 ◽  
Vol 10 (3) ◽  
pp. 107 ◽  
Author(s):  
T. Helle ◽  
J. Aspi ◽  
S.-S. Kilpelä
Keyword(s):  
Stand Density ◽  
Grazing Pressure ◽  
Clear Cut ◽  
Clear Cutting ◽  
Logging Residue ◽  
The Mean ◽  
Pine Stands ◽  
Reindeer Lichens ◽  
Group Density ◽  
Scots Pine Stands

The study was carried out in Kuusamo (66&deg;15'N, 29&deg;05'E) and Inari (68&deg;30'N, 28&deg;15'E), northern Finland, where 24 and 22 Scots pine stands were studied respectively. Clear-cutting (logging residue) caused a decline in lichen biomass for some few years, but otherwise the age of the stand had no effect upon lichen biomass. Instead, a positive correlation was found between litter/logging residue and the mean height of lichens; in Kuusamo, logging residue decreased significantly with the age of the stand. Grazing pressure in terms of fecal group density increased with the age of the stand. The preference of old forests came visible also as a lower mean height of lichens, which eliminates the possibility that the preference of old forests is associated only to the use of arboreal lichens. In Inari, grazing pressure sharply increased after the stand had reached the age of 100 years despite scarce litter/logging residue and fair lichen ranges in younger forests; there prevailed a negative correlation between stand density and grazing pressure. It has been suggested that there might be three main reasons for reindeers preferring old forests: 1) hardening of the snow (because of winds) on clear-cut areas, 2) logging residue preventing digging for the food beneath the snow, and 3) poor visibility in young pine stands (Inari) which might increase predation risk.

Age, stand density, and tree size as factors in root and basal grafting of lodgepole pine

2005 ◽  
Vol 83 (8) ◽  
pp. 983-988 ◽  
Author(s):  
Erin C Fraser ◽  
Victor J Lieffers ◽  
Simon M Landhäusser
Keyword(s):  
Pinus Contorta ◽  
Early Stage ◽  
Lodgepole Pine ◽  
Stand Density ◽  
Tree Age ◽  
Stand Development ◽  
Factors Associated ◽  
Tree Distribution ◽  
Pine Stands ◽  
Exposed Root

This study investigated stand factors associated with the rate of root graft formation in lodgepole pine stands. Forty plot areas, each containing 10 trees, were excavated in pure, even-aged pine stands in western Alberta. Exposed root systems were examined for grafts and various stand measurements were recorded at each plot. Results indicate that the number of grafts per square metre is controlled by plot tree density and tree diameter. Also, the percentage of grafted trees increased with both increasing tree age and decreasing distance between trees. Grafts also appear to form relatively early in stand development; the majority of grafts in the present study had formed by the time roots were 20 years old and 50 mm in diameter. These results suggest that grafting is a common occurrence in lodgepole pine stands where trees are <109 cm apart, which translates to a density of approximately 8500 stems/ha (based on even tree distribution). However, even clumps within relatively low density stands are likely to be grafted from a relatively early stage of development.Key words: Pinus contorta, graft formation, stand dynamics.

scholarly journals Simulating yields of managed, dwarf mistletoe-infested lodgepole pine stands /

1971 ◽  
Author(s):  
Clifford A. Myers ◽  
Frank G. Hawksworth ◽  
James Laning. Stewart ◽  
Keyword(s):  
Lodgepole Pine ◽  
Dwarf Mistletoe ◽  
Pine Stands

Effect of spacing in lodgepole pine stands on incidence of Atropellis canker

1986 ◽  
Vol 62 (2) ◽  
pp. 91-95 ◽  
Author(s):  
W. Stanek ◽  
J. C. Hopkins ◽  
C. S. Simmons
Keyword(s):  
Lodgepole Pine ◽  
Control Measure ◽  
Stand Density ◽  
The North ◽  
Pine Stands

Atropellis cankers on lodgepole pine were counted in Alberta plots spaced to 500, 1000, 2000, 4000 or 8000 trees per hectare. Cankers were counted just after thinning in 1967, and again in 1969, 1971 and 1983. After spacing, fewest cankers developed at 500 trees per hectare, most at 4000 and 8000 per hectare. Number of cankers developed after spacing was directly related to stand density, linearly when both were transformed to logarithmic scales, and was unrelated to site aspect. Atropellis cankers were found most frequently or the north and northwest sides of stems. Spacing as a control measure is recommended.

scholarly journals Stocking Control Procedures for Multiaged Lodgepole Pine Stands in the Northern Rocky Mountains

2003 ◽  
Vol 18 (1) ◽  
pp. 15-21
Author(s):  
Kevin L. O'Hara ◽  
Cassandra L. Kollenberg
Keyword(s):  
Leaf Area ◽  
Rocky Mountains ◽  
Lodgepole Pine ◽  
Stand Density ◽  
Control Model ◽  
Basic Unit ◽  
Age Classes ◽  
Area Index ◽  
Northern Rocky Mountains ◽  
Pine Stands

Abstract Patterns of leaf area distribution in multiaged lodgepole pine stands were used to develop a stocking control model. This model, the Lodgepole Pine–Multi-aged Stocking Control Model (LPP–MASAM), allows the user to design multiaged stand structures for implementation in lodgepole pine stands in the northern Rocky Mountains. The model is suitable for designing stands with two or three age classes, or two canopy strata. These multiaged stands represent a management alternative to even-aged stands where vigorous stands exist and windthrow is not a major constraint. The model requires the user to divide stands into components such as age classes or canopy strata that are the basic unit for growing space allocation. Growing space is represented by leaf area index. Stocking regimes are assessed over a single cutting cycle using projections of volume increment, stand density and tree vigor. Example stocking regimes are provided as are internet links to access the model. West. J. Appl. For. 18(1):15–21.

RECOMMENDED FOEEST PEACTICE FOR NEW ENGLAND

1941 ◽  
Vol 17 (4) ◽  
pp. 155-161 ◽  
Keyword(s):  
New England ◽  
General Rule ◽  
Partial Cutting ◽  
Minimum Requirement ◽  
Clear Cut ◽  
Clear Cutting ◽  
Forest Practices ◽  
Paper Birch ◽  
Old Trees ◽  
Mature Stands

Without debating the question of public regulation of private timberlands, the Committee felt that a useful purpose would be served by reviewing and compiling existing information on desirable forest practices for New England and has undertaken to condense this information into simple workable rules which would keep the forests of this region continuously and economically productive.As a minimum requirement forest practice rules should aim to stop unnecessary forest destruction and deterioration and keep the land reasonably productive. Under certain conditions clear cutting may be undertaken without jeopardizing this objective but such cutting should be confined to harvesting mature stands containing satisfactory reproduction or in the nature of salvage. Partial or selective cutting should be the general rule and, so far as practicable, all desirable immature trees should be preserved for future growth.In the spruce-fir region the main effort should be toward keeping heavily stocked stands which are inadequately stocked with reproduction from being clear cut. Spruce-fir rules are designed to favor partial cutting where reproduction is lacking, yet prevent windfall due to excessive removal.In the northern hardwoods region a cleanup of the poorer old trees is urgently needed, with protection of stands under 60 years of age from heavy cutting except in aspen and paper birch which are considered mature at 30 and 40 years.In the white pine, pine-oak, and oak regions partial cutting should be the rule but clear cutting is permitted under certain conditions.

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