Focus on Field Stations
WIND RIVER CANOPY CRANE RESEARCH FACILITY AND WIND RIVER EXPERIMENTAL FOREST
Introduction
Rising over 75 m into the air, the Wind River Canopy Crane circles slowly above 500-year-old Douglas-fir–west- ern hemlock forest in the Thornton T. Munger Research Natural Area (RNA). The crane swings around an area of 2.3 ha, carrying a 4- or 8-person gondola along its 85 m long jib (see cover, this Fig. 2. Map of the Wind River Experimental Forest, including the T. T. Munger issue of the ESA Bulletin). From the RNA and WRCCRF, located in southwestern Washington State. gondola one can gaze over the entire old-growth canopy of the RNA, beyond to the surrounding Wind River Experi- The Wind River Canopy Crane Re- The WREF includes a mosaic of mental Forest, east and west to the search Facility (WRCCRF) and Wind age classes resulting from a major fire Western Cascades of Washington State, River Experimental Forest (WREF; in the late 1840s, the extensive 1902 south across the Wind River Valley to Fig. 2) have a close and exciting sym- Yacolt Burn (Fig. 3) and subsequent re- the Columbia Gorge, or down into the biosis. The crane lies within an RNA burns, and a variety of stands that have lacy, undulating canopy of lichen- and that has remained in more or less natu- been managed since the early 1900s. bryophyte-laden conifers. The operator ral condition since the last major forest The Yacolt fire burned over 200,000 slowly glides the gondola over the tree- fire about 500 years ago (Franklin acres (81,000 ha) and 38 people died. It tops before descending next to a tree 1972). The 478-ha (1,180-acre) RNA is burned more than 36 hours, at speeds or snag of interest to the researcher. surrounded by the Wind River Experi- up to 87 mph, with flame lengths of 30 Whether studying atmospheric carbon mental Forest. Near the RNA is a large feet and a heat intensity of 1,000˚F. fixation or sampling foliose lichens on (39-ha), newly abandoned nursery field There were at least five re-burns. The branches of 60-m trees, the opportunity that has been plowed and irrigated original fire was started by slash and to study within the canopy, face to face since the early 1980s. settler fires fanned by east winds. with the trees, is exciting (Fig. 1).
Fig. 1. Examining needles for herbivory at the top of a 60-m Douglas-fir. Fig. 3. J. V. Hofman, early Wind River scientist, standing amidst the Yacolt burn.
July 2003 115 ics, reproductive strategies, adapt- cates with the crane operator to posi- ability, and growth potential of Dou- tion the gondola in suitable locations glas-fir forests (Isaac 1943). It is also for research purposes. In addition, the here in 1977 that the first efforts at arbornaut is trained in vertical rope res- actually describing old-growth forests cue and, in case of emergency, can took place (Franklin et al. 1981). evacuate personnel from the gondola. The WRCCRF is a University of One exceptional aspect of work- Washington College of Forest Resources ing at the WREF and WRCCRF is the facility, managed in cooperation with scientific foundation built by past re- the USDA Forest Service Pacific North- search and monitoring. Forestry re- west Research Station, the Gifford search has been ongoing at Wind Pinchot National Forest, and the West- River since the early 1900s. Many ern Regional Center of the National permanent plots have been estab- Institute for Global Environmental lished in the experimental forest and Change (Department of Energy). The its environs, providing opportunities Pacific Northwest Research Station, in for a wide variety of both silvicultural cooperation with the Gifford Pinchot and ecosystem studies (Fig. 5). The Fig. 4. T. T. Munger measuring trees in National Forest, manages the WREF, array of age classes lends itself to one of the earliest permanent study plots. which is 4,208 ha in size and divided ecosystem process studies across into two blocks, the Trout Creek and chronosequences. The experimental The WREF/WRCCRF complex is Panther Creek divisions (Fig. 2). forest and the RNA designations pro- within the Mt. Adams Ranger District The canopy crane, with its forest vide good administrative protection of the Gifford Pinchot National For- canopy access capabilities, is a central for research studies and plots. est. The well-known Pacific Crest feature of the WRCCRF and WREF The canopy crane has been used for Trail that travels along the Cascade (Shaw et al., in press). The old-growth a broad range of research, including crest from Canada to Mexico passes forest (~ 500 years old) under the crane organismal biology and ecology, pro- through the experimental forest, less is a mix of Douglas-fir, western hem- cess ecology, tree ecophysiology, and than a mile from the RNA. Numerous lock, western redcedar, Pacific silver global climate change/carbon dynam- other Research Natural Areas are in fir, and Pacific yew. Researchers step ics. The Annual Wind River Canopy the immediate vicinity, as are several into a gondola at the forest floor and are Crane Research Facility Scientific Con- Wilderness Areas, Mt. St. Helens Na- lifted up to their desired locations. The ference (The ninth was held in 2003) tional Volcanic Monument, and Mt. crane is operated by a Research Tower highlights current research at the site Rainier National Park. Portland, Or- Crane Operator who sits 74 m above the and provides an opportunity for a di- egon, a major Northwest metropoli- forest floor in an operator’s cab. An verse group of scientists to communi- tan center, is an hour away, and is arbornaut accompanies researchers in cate and collaborate. Recent programs accessed by driving through the spec- the gondola. The arbornaut communi- have included 35 papers, with about 70 tacular Columbia River Gorge Na- people attending. The conference oc- tional Scenic Area. curs in the historic Hodgson-Lindberg The WRCCRF was established in Training Center (Fig. 6). 1995, but the surrounding experimen- tal forest provides an historical context that goes back as far as 1909 when Environment Thornton T. Munger began a long-term study on the growth of Douglas-fir Located in the central Cascade (Fig. 4) in what was to become the mountain range of southern Washing- Wind River Experimental Forest some ton State, the Wind River Valley is a 25 years later. Munger also had the north–south oriented valley that prescience to establish one of the first merges into the Columbia River RNAs in the region, later named after Gorge, a major geographical feature him, and now the site of the canopy that cuts through the Cascade moun- crane. This experimental forest is where tain range at the border of Oregon the earliest research on Douglas-fir and Washington State (Fig. 7). The was done, results that established the gorge connects the maritime-influ- most basic tenets for silviculture and enced regions of western Oregon and management of the great Douglas-fir Washington to the continental influ- forests in western Washington and Fig. 5. Installing soil moisture probes ences of eastern Washington and Or- Oregon. Long-term research in the WREF in an old-growth forest adjacent to per- egon. This sea-level environmental has provided insights into tree genet- manent sample plots. and ecological gradient from the
116 Bulletin of the Ecological Society of America The climate is characterized by high rainfall (2223 mm/yr), moderate temperatures (mean annual tempera- ture 8.7˚C), winter snowpack, and summer drought (June, July, and Au- gust receive < 5% of annual precipi- tation) (Fig. 8). The forests are tem- perate coniferous seasonal rain for- ests due to the contrast in seasonal rainfall. Rain-on-snow, freezing rain, graupel events, and cold east winds are common in winter. The Wind River Experimental Forest is blanketed with young, ma- ture, and old forests of Douglas-fir, western hemlock, western redcedar, grand fir, Pacific silver fir, noble fir, Pacific yew, western white pine, bigleaf maple, and Pacific dogwood. The diversity of forests is also ex- Fig. 6. The Hodgson-Lindberg Training Center at the Wind River Work Center, pressed at the head of the valley Gifford Pinchot National Forest, site of the WRCCRF Annual Scientific Confer- where lodgepole pine, Engelmann ence, various workshops, and meetings. spruce, and western larch occur. A small cedar swamp, beaver ponds, western hemlock/Douglas-fir forests of the experimental forest; Mt. Hood and marshes provide areas of aquatic, of the west to the shrubsteppe com- is about 50 km to the south. Within semiaquatic, and moist habitat. munities to the east occurs in less the valley and a central feature of the than 100 km. experimental forest is Trout Creek Research Volcanism characterizes the Cas- Hill, a Quaternary volcano, which re- cade Mountains and the Wind River leased lava flows that filled the valley Biodiversity Valley. Bedrock in the valley is com- floor about 340,000 years ago. Soils posed of Miocene/Oligocene and within the valley, mostly derived The spatial and temporal organi- Quaternary volcanic flows, as well as from volcanic ash, are generally stone zation of biodiversity, as well as the intrusive Miocene basalts. Mt. St. free and may be from eruptions of maintenance of habitat to protect rare Helens is approximately 30 km north Mt. St. Helens. and endangered organisms, has been an ongoing research and monitoring topic in the Wind River Valley for some time. The T. T. Munger RNA was established in 1926 to protect a large tract of low-elevation old- growth forest, and includes wetlands. Species of concern include Spotted Owl (Strix occidentalis), Goshawk (Accipiter gentilis), Sierra woodfern (Thelypteris nevadensis) fringed pinesap (Pleuricospora fimbriolata), Clackamas corydalis (Corydalis aquaegelidae), the polypore fungus Albatrellus skamanius, and the li- chens Tholurna dissimilis and Pseudocyphellaria rainierensis. The WREF played a central role in a ma- jor U.S. Forest Service effort to un- derstand the relationship of stand age and vertebrate biodiversity. Fig. 7. Wind River Valley looking north. Mt. St. Helens is in the upper right, Bunker The epiphytic plant community Hill in the center, with the old Wind River Nursery to the west, and the Trout Creek has been intensively studied on the Division of the Wind River Experimental Forest is located above the nursery area. WREF as well as the WRCCRF.
July 2003 117 The vertical light environment, crown organization, epiphyte distribution, bird use, epicormic branching in Douglas- fir, and field testing of models have utilized the crane. One recent finding is that old-growth forests tend to be open in the upper canopy and bottom heavy with structure, a reverse of the pattern in young forests. The ability of Douglas-fir trees to maintain foli- age by the production of epicormic branches may help to explain why they can live so long.
Tree physiological ecology
How do big trees deal with water stress, and does this differ from small trees? What are the physiological limi- tations on growth as trees age and in- Fig. 8. Climate summary for Wind River Valley. Data are from the Carson National Fish crease in height? Is the phenomenon Hatchery, 1978–1998, about 5 km north of the Wind River Experimental Forest. of hydraulic lift common in forest trees of the Pacific Northwest and Biodiversity, community organization, Andrews Experimental Forest in the what are its consequences? How do vertical occurrence, association with 1980s to experimentally determine fertilizer and tree spacing affect tree structure and forest age, nitrogen the effect of gaps on ecosystem pro- productivity? How does water utiliza- fixation, influence of UV, and physi- cess. These gaps range in size, are tion scale with tree size, stand age, ological activity patterns have been located in young, mature, and old- and across species? These types of research topics. For example, research- growth forests, and data are continu- questions are being asked at Wind ers found 111 species of mosses and ing to be collected. River. Understanding the physiologi- lichens in 72 sample plots systemati- More recently, the WRCCRF has cal response and performance of trees cally placed in the canopy of the for- been used as an access tool to facili- is important in predicting how trees est around the WRCCRF, with a total tate intensive studies of forest struc- will grow, whether they sequester estimated dry mass of 2 Mg/ha. This ture as well as the development of carbon, and how they will respond to high biodiversity and biomass reveals structures in individual tree crowns. climate change (Fig. 9). the profound influence of forest age and structure on associated biota in these forests.
Forest structure, growth, and mortality processes
Forest structure, growth, and mor- tality in natural and managed stands, gaps, overstory influence on under- story vegetation and environments, tree structures, development and ag- ing of tree crowns, and a focus on chronosequences have been research topics here. The T. T. Munger RNA has 102 1-acre (0.4-ha) mortality plots established in 1948, and is still being remeasured over 50 years later. These plots have been instrumental in our understanding of the rates and causes of mortality in natural old- growth forests. Artificial gaps were Fig. 9. Physiological study of in situ tree photosynthesis using the gondola of the created in WREF and on the H. J. canopy crane.
118 Bulletin of the Ecological Society of America knowledge will be needed, based on changes in economic and social con- ditions, to select management sys- tems that will best meet a variety of ownership objectives.
Networks
The WRCCRF and WREF are inte- grated into many environmental, for- estry, facility, and research networks that leverage the investment made in this unique field station. The Wind River Experimental Forest is one of seven Forest Service experimental for- ests in Washington and Oregon. Wind River can be a part of cross-site com- parison studies, using sites selected to represent different environmental, veg- etation type, or other conditions useful Fig. 10. Helium balloon used for studies of meso-scale climate modeling, support- to broad-scale study objectives. The ing the Ameriflux instrumentation on the canopy crane. permanent plots at Wind River are also part of a network of plots established Carbon forest management practices have across the Pacific Northwest to charac- evolved and changed over the last 100 terize an array of forest types. The per- As the carbon cycle has become a years. Plots in a landmark heredity manent plot system in this region spans focus of research in order to understand study, in one of the first arboretums many Experimental Forests, Research the consequences of atmospheric and in the Northwest (Fig. 11), and in Natural Areas, several National Parks, climate change, WRCCRF and WREF several thinning studies, are still be- and National Forest systems lands, pro- have become focal research sites that ing measured. A long-term study on viding a strong base for characterizing are integrated into a national network. Trout Creek Hill begun in the early forest composition, structure, and pro- The Western Regional Center of the 1980s is looking at plantations that cesses of change in various age classes. National Institute for Global Climate used native species in pure plantings The Ameriflux instrumentation col- Change (WESTGEC) has established and in mixes across an array of lects year-round data on carbon flux an AMERIFLUX site at Wind River, spacings. This study is based on try- at this site and >90 others in North while also funding interdisciplinary ing to anticipate what kinds of future America and >200 sites in a global net- process research at multiple scales (Fig. 10). The old-growth forest is a sink for carbon, although not a strong one. However, year-to-year changes in weather patterns have a large effect. During cool, wet years, the forest can be a strong sink. The influences of photosynthesis, water limitations on carbon sequestration, decomposition, fine-root production and phenology, nitrogen cycling, leaf diseases, weather patterns, light environments, and for- est structure on the carbon cycle are all under investigation.
Silviculture and forest mensuration
Silviculture research that began at Wind River in the early 1900s has continued in many forms ever since. The emphasis on this research has gone through numerous changes as Fig. 11. Wind River Arboretum in 2003, with inset from 1912.
July 2003 119 eral public for educational endeavors. Main attractions are the canopy crane and experimental forest, T. T. Munger Research Natural Area, Wind River Arboretum, alder growth strips, silvicul- tural demonstration areas, artificial re- search gaps, chronosequence of forest age classes, and the worlds’ largest hem- lock dwarf mistletoe infection center! In recent years, WRCCRF has given educational canopy lifts to 400–500 people/year in about 25–30 organiza- tions. Tours begin with safety orienta- tions and suiting up in full body har- nesses, followed by a lift into the canopy to discuss forest canopy structure and natural history, the research program, and the benefits to society of forest re- search. The experience of traveling 65 Fig. 12. The PNW House (CCC construction) used for bunking field crews year-round. m up through a forest canopy of lofty Douglas-fir and western hemlocks is unsurpassed. No other method brings work called Fluxnet. These networks University of Washington Field Stations such unique perspectives of the canopy are key to understanding ecosystem system
120 Bulletin of the Ecological Society of America tions. High school students who re- Web pages: WRCCRF
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