Progress 06/01/03 to 12/31/06
Outputs
The goal of the Ecological Society of America's SEEDS program (Strategies for Ecology Education, Development, and Sustainability) is to enhance diversity within the field of ecology. Undergraduate students from minority or underrepresented groups who are granted SEEDs fellowships are paired with academic mentors to undertake independent ecological research. Funds provided by this grant support research expenses for Sheena Hillstrom, an undergraduate student from Washington State University. Sheena's independent research explores effects on vegetation and soils of burning logging slash in piles following conifer removal from mountain meadows in western Oregon. It also addresses the tradeoffs between pile and broadcast burning, two alternatives for reducing fuels as part of meadow restoration treatments. During the past year, field and laboratory studies were completed as were preliminary analyses of vegetation and soils data. These were made available on a WEB site that
describes the broader restoration experiment (http://depts.washington.edu/bgridge/).
Impacts
Disposal of slash through pile burning represents a tradeoff between extent and intensity of disturbance. Burn scars covered only 10% of the ground surface in these treatments, but the centers of these scars had significant exposure of mineral soil and concentrations of NH4+-N, greatly exceeding those in broadcast burned treatments. Recovery of native vegetation may be problematic within burn scars and these intensely disturbed sites may serve as foci for future invasion of weedy species. Gathering of slash in piles can be effective at reducing ground fuels, but hand piling can be labor intensive. At the same time, piles can be burned in late fall or early winter at a time when fire risk, as well as cost and effort associated with containment, is low. By comparison, weather conditions for broadcast burning are more restrictive, and fire containment requires greater effort and cost.
Publications
- No publications reported this period
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Progress 10/01/05 to 10/01/06
Outputs
We are studying the consequences of conifer encroachment and the potential for restoration of dry, montane meadows in the western Cascade Range of Oregon. In a region dominated by coniferous forest, montane meadows contribute greatly to landscape diversity, wildlife habitat, and other important ecological functions. However suppression of fire and changes in climate and grazing pressure over the past century appear to have resulted in rapid expansion of forest into meadow openings. Faced by gradual loss of habitat, resource managers are experimenting with prescribed fire as a tool for meadow restoration, but with limited knowledge of the ecology and dynamics of these systems. To guide these efforts, we have designed a program of research at Bunchgrass Ridge. Our goals are to increase understanding of the history and dynamics of these systems and to evaluate the potential for meadow restoration through tree removal and prescribed fire. Three studies (two completed)
contribute to these goals. The first is a retrospective analysis of vegetation change using a chronosequence of open meadow to old forest habitats. The second is an analysis of the soil seed bank and its potential to contribute to restoration of the meadow flora. Two MS theses (Haugo 2006, Lang 2006) containing the results of these studies have been completed and manuscripts have been submitted for publication. The third study is a large-scale replicated experiment utilizing two treatments (tree removal with and without fire) and a control. Logging treatments were completed in winter 2006 (on snow, to minimize soil damage) and experimental burning was completed in fall. We also completed measurements of fuel loadings and fuel consumption. Post-treatment measurements of vegetation response will be made in summer 2007.
Impacts
Retrospective studies point to several factors that may limit the potential for restoration of dry montane meadows in the western Cascades that have experienced conifer encroachment: (1) progressive loss of meadow species and plant abundance with time, (2) absence of a viable seed bank for most meadow taxa, and (3) possible competition with understory herbs and ruderal species in the seed bank that may respond positively to overstory removal or fire. Implementation of logging and burning treatments illustrate that such restoration treatments are operationally feasible.
Publications
- Haugo, R. D. 2006. Vegetation responses to conifer encroachment in a dry, montane meadow: a chronosequence approach. M.S. thesis. University of Washington, Seattle, Washington. Lang, N. L. 2006. The soil seed bank of an Oregon montane meadow: consequences of conifer encroachment and implications for restoration. M.S. thesis. University of Washington, Seattle, Washington.
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Progress 10/01/04 to 10/01/05
Outputs
We are studying the consequences of conifer encroachment and the potential for restoration of dry, montane meadows in the western Cascade Range of Oregon. In a region dominated by coniferous forests, montane meadows contribute greatly to landscape diversity, wildlife habitat, and other important ecological functions. However, in many areas, suppression of fire and changes in climate and grazing pressure over the last century have led to rapid succession of meadow to forest. Faced by gradual loss of these habitats, resource managers are experimenting with prescribed fire as a tool for meadow restoration, but with limited knowledge of their ecology and dynamics. To better guide these efforts, we have designed a program of research and adaptive management at Bunchgrass Ridge. Our goals are to increase understanding of the history, dynamics, and variability of these systems, and to evaluate the potential for restoration. Three studies contribute to these goals: A
retrospective analysis of vegetation change along a transition from open meadow to old forest. An analysis of the soil seed bank and its potential to contribute to restoration of the meadow flora. An experiment to examine vegetation responses to tree removal and prescribed fire, and how responses vary with initial composition and structure. During the past year, we completed analyses for the first two studies. These contribute to two MS theses (in progress). The results of work to date were also presented at the following meetings/workshops: Halpern, C. B., R. D. Haugo, N. L. Lang, J. A. Antos, K. M. Smith, F. J. Swanson, and J. H. Cissel. 2005. Restoration of dry, montane meadows through prescribed fire, vegetation and fuels management: A program of research and adaptive management in western Oregon. 2005 Joint Fire Science Program Principal Investigator Workshop, San Diego, CA. Haugo, R. D, and C. B. Halpern. 2005. Conifer encroachment in a dry, montane meadow, western Cascade
Range, OR. 78th Annual Meeting of the Northwest Scientific Association, Corvallis, OR. Lang, N. L., and C. B. Halpern. 2005. Soil seed bank dynamics of an Oregon montane meadow: implications of conifer encroachment. 78th Annual Meeting of the Northwest Scientific Association, Corvallis, OR.
Impacts
The results of our retrospective studies point to a number of factors that may limit the potential for restoration of meadows that have experienced long-term encroachment: (1) significant declines in abundance and progressive loss of meadow species with time, (2) absence of a viable seed bank for most meadow taxa, and (3) potential competitive interactions with forest herbs and ruderal species that may respond positively to overstory removal or soil disturbance.
Publications
- No publications reported this period
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Progress 10/01/03 to 09/30/04
Outputs
In many regions of the western U.S., long-term suppression of wildfire has facilitated encroachment of natural meadows by conifers. Encroachment is widespread on many dry, montane slopes in the western Cascade Range. Faced by gradual loss of these critical habitats, resource managers have begun to experiment with prescribed fire as a tool for meadow restoration. With limited knowledge of the historical role of fire in these systems, managers have little information to guide restoration efforts. We have initiated a program of research, adaptive management, and outreach at Bunchgrass Meadow (Willamette National Forest, Oregon) that will contribute to our understanding of the dynamics of these systems and to their restoration and maintenance. Our studies include: (1) a retrospective analysis of the spatial and temporal patterns of conifer encroachment and associated changes in ground-layer vegetation and (2) a study of vegetation responses to experimental restoration
treatments, including tree removal with and without prescribed burning. Ultimately, we seek to identify the types of management approaches that are successful and the initial conditions that are conducive to restoration of meadows. During the past year, we completed field sampling for study 1 and pre-treatment measurements for study 2. Within four 1 ha plots (intensive plots) all trees >1.4 m tall were mapped, measured for diameter, and aged. Within 64, 10 x 10 m subplots within each of these, understory vegetation was sampled for species composition and abundance, and a hemispherical canopy photo was taken to quantify light availability. Stand maps (spatial locations of trees) were constructed and size and age structures were summarized. During the coming year we will analyze temporal and spatial patterns of forest development and the relationships between overstory structure/age and changes in understory composition. Within five additional plots (non-intensive plots), similar
measurements of canopy structure, light availability and understory composition were taken. In combination, these nine plots serve as the experimental plots for study 2 (three replicates of each of three treatments: control, cut/remove all trees, and cut/remove all trees and broadcast burn). Treatment implementation will begin during winter 2005
Impacts
Ours is the first study to quantitatively examine the relationships between forest encroachment and changes in meadow vegetation. Stand age structures reveal massive invasion of conifers during the middle part of the 20th century, synchronous with removal of sheep grazing and a transition from warmer/drier to cooler/wetter conditions. Spatial distributions of trees suggest that pioneering lodgepole pine facilitates invasion of grand fir. At the same time, forest herbs quickly colonize beneath established trees leading to fairly rapid transition from a ground vegetation dominated by meadow species to one dominated by forest understory plants.
Publications
- No publications reported this period
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