The old study was established in the Blacks Mountain Experimental Forest (BMEF) in the 1930's and 1940's and examined different levels of harvesting timber. It was designed to determine what minimum levels of timber harvest could be economically feasible over large areas, and to determine the differences in tree growth over time. The new study takes a holistic approach to answer complicated ecological questions by examining the responses and interactions of many forest components to different forest structures within an interdisciplinary, experimental framework. A key goal of the research is to provide useful information for achieving the necessary balance of forest management to simultaneously meet the demands of people and the needs of a functioning forest and its soils, plants, invertebrates, and wildlife. Questions to answer include: How do the forest's functions, or ecological processes, change through time? How do they respond to different forest management strategies?
The response from many scientists working in different disciplines was an overwhelming "yes." As they talked about the importance of the 50-year data base at Blacks Mountain, they began to see new opportunities for research within a different framework. Out of the first meeting in 1991 came a commitment to develop a new research plan for Blacks Mountain that would address some of today's concerns. The study would be on the cutting edge for developing research technologies and integrating information to answer large, complex questions.
"We had always given lip service to interdisciplinary studies," Oliver says, "but we really didn't know how to go about it."
The team has now worked together for more than four years and has developed techniques and processes necessary to conduct interdisciplinary research on a variety of scales.
Both sets of these questions are directly related to important aspects of
Blacks Mountain Experimental Forest is largely forested with eastside pine, a major forest community that extends from Baja California north through eastern Oregon and Washington and into British Columbia. These forests consist primarily of ponderosa and Jeffrey pine, with white fir and incense-cedar also present. Eastside pine is valuable for timber and cattle production, clean water, outdoor recreation, and habitat for a variety of wildlife.
Major problems also exist within this forest type; temperature extremes -- hot in summer and cold in winter -- and low precipitation combine to create difficult growing conditions. Decades of use and wildfire exclusion in the 20th century, combined with other factors, have resulted in less than fully productive forests that seem to be prone to bark beetle outbreaks. The risk of catastropic fire is high, and many ecological processes have been altered.
Both future forest health and the economic base of local communities depend on new management techniques. As foresters move more and more toward practices that emphasize long-term productivity and ecologically sound management strategies, they will rely heavily on information from research: basic ecological information about the way forest ecosystems function.
Ecosystem interactions and emergent properties can be understood only if two or more factors are studied together. Physically, this is difficult when some factors (such as bacterial mineralization of organic matter) are studied on a micro-geographic or temporal scale, while others (such as habitat needs and/or reproductive success of cavity-nesting birds) are studied more broadly. The relationship between, and influences of, the various forest properties and processes can be determined by knowing the exact location of the data in the landscape and, in time, the community conditions that it represents. Findings can then be discussed with specialists in other disciplines who are involved with similar or related communities. Spatial and temporal integration of the findings from field studies of differing scales will be achieved by referencing all data to permanently monumented plot centers accurately located on a 100-meter grid. This grid will facilitate the integration and extrapolation of information obtained from periodic sampling through time.
To further facilitate this, geographically-referenced digital orthophotos will be used to determine the spatial distribution of plant communities. The photos will permit a description of the landscape at varied spatial scales, and subsequent photos will show how the treatments and vegetation response to such have altered the landscape through time. Data will be stored in a corporate relational data base, and analysis will include the use of geographic information systems.
Structure refers to the shape of a forest: its height, the diameter of trees, and the spacings around trees and groups of trees. The study design compares the effects of two different forest structures (high diversity and low diversity), two grazing strategies, and two fire treatments on forest ecology. The treatments will set the evolution of forest structures on eight different paths. Various forest attributes will repond differently to these treatments through time.
The study consists of twelve 250-acre plots. Six of the plots will be harvested to high structural diversity and six to low structural diversity. These structures will be created by timber sales planned for the summers of 1995, 1996, and 1997. Grazing will be excluded from half of the high diversity and half of the low diversity plots. Each of the 250-acre plots will be split, and fire will be re-introduced (and maintained on a regular basis) on each of the 125-acre splits.
After logging, each 250-acre high diversity treatment area will contain many large, old trees, abundant snags, multiple canopy layers with dense clumps of smaller trees, and small openings. Each low structural diversity treatment area will have few large trees and snags, and a single canopy layer with trees well spaced, and a few large gaps in the forest canopy.
The fire treatment will reduce the amount of woody debris and forest floor litter on half of each of the treatment areas. It will also increase nutrient availability through mineralization, provide optimum places for plant seed germination, and stratify seeds, which encourages them to sprout.
The grazing treatments will result in the trampling of woody debris, mixing of upper soil layers, and consumption of sprouting grasses and forbs.
The responses of various forest attributes (including soils, vegetation, genetics, and wildlife) and the interactions of ecological processes (nutrient mineralization, plant growth, and wildlife population changes) that will result from the treatments are unknown. The important question is: is there a real difference between management strategies through time?
Scientists are invited to join the group if they think they have something to contribute to the research at Blacks Mountain.
Kathy Harcksen, a full-time team leader, coordinates the project. Her responsibilities are to facilitate the efforts of the research team, oversee planning, and serve as liaison to National Forest and other cooperators. This role is necessary to relieve scientists of the administrative burden and allow them to continue their investigative role in research.
All of the studies are planned with certain objectives in mind; scientists want to learn things that will have practical application in forestry. But no one knows exactly what will come out of this work. "We expect surprises," Oliver says. "Through the collaboration of scientists working in different disciplines, we will undoubtedly find many environmental relationships we simply cannot foresee."
In the past, most ecological studies were not designed to assess the effects caused by specific activities, nor were they intended to answer questions relevant to more than one discipline. As a result, it has been difficult to draw broad conclusions on the effects of activities on the array of ecological components within a forest. At Blacks Mountain, scientists have put considerable effort "up front" into planning a study that would answer big questions on biodiversity and sustainable productivity and that would provide statistically-sound information for years to come. That is the special interest of Dr. Pat Shea. Shea was involved in large insecticide studies in the 1960's and 1970's. Those studies, which included analyzing the effects of insecticides on birds and wildlife, have helped him appreciate the importance of good experimental design.
"Fifty to 100 years from now, we want researchers and managers to have confidence in the data base," he says.
The research team will determine the interaction of these components before and after treatments are installed, as well as any differences between treatments. Through time, any significant differences in forest management strategies will become evident.
Scientists involved in the Blacks Mountain study have, essentially, a lifetime commitment to their work and to this particular project. "No one has to do this research," according to Kathy Harcksen. "They have a commitment to finding the answers to larger questions, and each of them subscribes to the philosophy of interdisciplinary research. Each one has given up a lot, betting that the pay-off in gaining the knowledge pertinent to understanding ecological systems will come in the long run."
To learn more about the studies at Blacks Mountain Experimental Forest, refer to the article titled "Long Term Response of Old Growth Stands to Varying Levels of Partial Cutting in the Eastside Pine Type," by Dolph, Mori, and Oliver, in the Western Journal of Applied Forestry, 10(3):101-108 (1995). This article is now in press.