SPECIAL REPORT THE HyP3 PROJECT Pattern, Process, and Productivity in Hypermaritime Forests of Coastal British Columbia 2005 A SYNTHESIS OF 7-YEAR RESULTS Ministry of Forests Forest Science Program The HyP3 Project Pattern, Process, and Productivity in Hypermaritime Forests of Coastal British Columbia A Synthesis of 7-Year Results Compiled & Edited by: Allen Banner, Phil LePage, Jen Moran, & Adrian de Groot Ministry of Forests Forest Science Program The use of trade, firm, or corporation names in this publication is for the information and convenience of the reader. Such use does not constitute an official endorsement or approval by the Government of British Columbia of any product or service to the exclusion of any others that may also be suitable. Contents of this report are presented as information only. Funding assistance does not imply endorse- ment of any statements or information contained herein by the Government of British Columbia. Library and Archives Canada Cataloguing in Publication Data Main entry under title: The HyP3 Project : pattern, process and productivity in hypermaritime forests of coastal British Columbia : a synthesis of 7-year results (Special report series, 0843-6452 ; 10) Includes bibliographical references: p. 0-7726-5320-8 1. Forest ecology - British Columbia - Pacific Coast. 2. Sustainable forestry - British Columbia - Pacific Coast. 3. Forest management - British Columbia - Pacific Coast. 4. Forests and forestry - British Columbia - Pacific Coast. I. Banner, Allen, 1954- . II. British Columbia. Forest Science Program. II Series: Special report series (British Columbia. Ministry of Forests) ; 10. 106.2.737 2005 333.75'09711 2005-960066-7 Citation: Banner, A., P. LePage, J. Moran and A. de Groot (editors). 2005. The HyP3 Project: pat- tern, process, and productivity in hypermaritime forests of coastal British Columbia – a synthesis of 7-year results. B.C. Min. For., Res. Br., Victoria, B.C. Spec. Rep. 10. <http://www.for.gov.bc.ca/hfd/pubs/Docs/Srs/Srs10.htm> Prepared by Allen Banner, R.P.Bio., R.P.F. Research Ecologist, B.C. Ministry of Forests Smithers, BC Phil LePage, R.P.F. Research Silviculturist, B.C. Ministry of Forests Smithers, BC Jen Moran B.C. Ministry of Forests Smithers, BC Adrian de Groot, R.P.Bio. Drosera Ecological Consulting Smithers, BC © 2005 Province of British Columbia When using information from this or any Forest Science Program report, please cite fully and correctly. Copies of this report may be obtained, depending upon supply, from: Crown Publications 521 Fort Street, Victoria, BC (250) 386-4636, www.crownpub.bc.ca For more information on Forest Science Program publications, visit our web site at: http://www.for.gov.bc.ca/hfd/pubs/index.htm ii CONTRIBUTING AUTHORS British Columbia Ministry of Forests Allen Banner (project leader), Marty Kranabetter, Phil LePage, Dave Maloney, Karen McKeown, Jen Moran, Jim Pojar1 University of Waterloo Ramon Aravena, Taro Asada, Lisa Emili, Dan Fitzgerald, Chris Gainham, John Gibson, Sandra Lortie, Jonathan Price, Barry Warner Consultants Shauna Bennett (Bio Logic Consulting), Davide Cuzner (Viking Ecosystem Consultants), Adrian de Groot (Drosera Ecological Consulting), Colleen Jones (Shamaya Consulting) 1 Now affiliated with the Canadian Parks and Wilderness Society, Whitehorse, Yukon. iii EXECUTIVE SUMMARY The HyP3 Project (pronounced “hip Chapters 1 and 2 provide the back- cubed”) was initiated in 1997 to provide ground to the research, including a review an integrated research approach to the of previous studies. These chapters also study of pattern, process, and productivity present descriptions of the north coast in the hypermaritime forests of north landscape and the specific study areas, coastal British Columbia. The project has stand types, and ecosystems targeted for four main goals: the research. The geographic scope of the • Document the ecology of the blanket project encompasses the Coastal Western bog–upland forest complex of north Hemlock zone, Very Wet Hypermaritime coastal British Columbia. subzone, Central variant (CWHvh2) with- • Assess the feasibility of managing poor- in the North Coast and North Island– and low-productivity cedar–hemlock Central Coast forest districts of the Coast forests, which dominate the outer Forest Region. The blanket bog–upland coastal landscape, for timber and fibre forest complex of the CWHvh2 contains production. approximately 235 000 ha of lower-pro- • Define the extent of these sites and ductivity cedar-dominated stands that identify the potentially operable por- straddle the defined operability thresholds tion. for height class, merchantable volume, • Develop ecologically based manage- and site limitations. As market values for ment guidelines for these forests. redcedar and yellow-cedar improve, pres- The need for this research was made sure increases to alter the operability clear in the 1995 timber supply review for thresholds. This has already begun to the North Coast Timber Supply Area. occur on the north coast, and because this This report stated that the Chief Forester research is now under way, preliminary required better scientific information management guidelines can be in place before he would consider expanding the before operability pressures increase dra- operable land base into lower-productivity matically. From an ecological perspective, cedar-dominated (western redcedar [Thuja the outer coast of British Columbia is a plicata] and yellow-cedar [Chamaecyparis fascinating landscape and a major thrust nootkatensis]) forests. Research was re- of the research is simply to gain a better quired that would address basic ecosystem ecological understanding of these hyper- function (e.g., watershed and soil hydrolo- maritime forests and wetlands. gy, plant and soil ecology, succession and Chapter 3 describes studies of site and stand dynamics) and provide practical watershed hydrology and biogeochem- management guidelines for these forest istry. Water plays a pivotal role in shaping types. ecosystem function on the outer coast, This report presents a synthesis of the and thus hydrological studies are an HyP3 Project’s 7-year results. It provides important part of the HyP3 Project. To an overview of the project to date and produce water budgets for small water- summarizes initial results for each of the sheds and predict the potential effects of project components—hydrology and bio- timber harvesting on these water budgets, geochemistry, ecosystem processes, classi- watershed-level studies included moni- fication and inventory, and operational toring of precipitation, interception, trials. The report concludes with a chapter throughfall, and streamflow. Site-level on management interpretations. studies examined water table dynamics, iv hydrological linkages between sites, and Hydrological dynamics differ among natural soil drainage mechanisms such as forest types. Our study indicates that the soil pipes. Soil water chemistry across the cedar-dominated upland scrub forests spectrum of forest and bog ecosystems in (i.e., the target stands of the HyP3 Project; the CWHvh2 is also characterized. CWHvh2/01 sites) will likely have an on- Hypermaritime watersheds of the site hydrological response to harvesting CWHvh2 have a relatively low water stor- that is intermediate between the wetter age capacity. The shallow, dominantly swamp forests and the more productive organic, soils typical of these watersheds upland forests. Water tables are likely to have high water retention capacity, and rise slightly depending on specific site and are frequently saturated in this wet cli- soil characteristics. Compared with the mate. The small amount of available water upland scrub forests, the true swamp storage capacity in these soils means that forests are quite restricted in distribution significant runoff is generated from rela- on the coast. The swamps are more sensi- tively small storms. Compared with other tive to harvesting-induced hydrological locations, rainfall events in the CWHvh2 changes than upland forests; they should produce a larger hydrological response. not be harvested because of their impor- The decrease in canopy interception tance in receiving water and regulating after harvesting increases the amount of streamflow within a watershed, and their water received on the ground. At the greater potential for rising water tables. HyP3 study sites, the canopy intercepted Where scrub forests occur on flat or very 20–25% of the average annual rainfall. If gently sloping sites, a rise in the water these areas are clear-cut, the amount of table following timber harvesting is water requiring removal by existing expected and could have negative ecologi- hydrological processes can be expected to cal implications. Smaller rainfall events increase. The possible hydrological conse- would saturate these forest soils because quences of these increased water inputs of the reduced interception and transpira- include faster development and increased tion following canopy removal. This may volume of peak flows, higher water tables, hamper regeneration and promote paludi- and increased erosion resulting from fication, with the invasion of sphagnum overland flow. mosses and other wetland plants. As Organic soils (especially on disturbed forests regenerate, canopy interception sites) have high water retention and low and transpiration begin to increase again, cohesion qualities, and therefore the pos- but the time required for hydrological sibility of increased erosion must be con- recovery