[A group of 35 MN DNR managers and staff met recently to share progress on interdisciplinary forest management coordination and to identify strategies for continued progress. The group included commissioners; division directors, and regional and area managers from Forestry, Ecological Resources/Waters, and Fish and Wildlife; regional directors; and OMBS staff involved in forest management coordination. Regional and area staff presented updates on “Adaptive Forest Management Projects.” These projects were designed to improve the DNR’s ability to integrate multiple forest management objectives, monitor progress, and course correct when management practices are not effective in the face of change.
Michelle Martin, profiled approaches for integrating oak management and rare species conservation in a unique blufflands site in southeast Minnesota. Steve Piepgras, spoke about silvicultural treatments to diversify aspen stands for improved wildlife habitat and timber value while responding to new biomass markets. Bill Schnell discussed the Manitou Collaborative on the North Shore Highlands and its innovative work to diversify forest stands and restore conifers. Erik Thorson presented alternative practices to improve regeneration of jack pine.
Commissioners and division directors noted staff enterprise in tackling complex issues, trying new approaches, and using monitoring and evaluation to learn and adapt. Regional managers and directors then presented success stories in broader interdisciplinary coordination. The meeting wrapped up with discussion of continued challenges – issues requiring greater policy and management direction. These included high conservation value forests, school trust land issues, and roles and responsibilities for coordination among disciplines and Central Office, regional, and area staff.]
One of the major focus points of my position has been my involvement with the Manitou Collaborative and its Ecological Silviculture Patch Project. Like most forest management projects, it's taken a few years just to get the treatments setup, to coordinate objectives and design management prescriptions, and to offer timber sales to on auction. Fortunately we've made it this far, but it's going to take several decades before we truly see the fruits of our labor. Below is a summary of the project. By no means does this capture all of the subtle nuances involved with forest management, but hopefully it will give the reader a little insight into how we integrate ecology with silviculture, and how we might adapt to future changes in the environment.
MN DNR Divisions of Forestry, Wildlife, Ecological Resources, Fisheries, and Office of Management and Budget.
Manitou Collaborative Partners include The Nature Conservancy, USFS-Superior National Forest, Lake Co. Land Department, MN DNR, MN Forest Resource Council-NE Landscape, and Wolf Ridge Environmental Learning Center.
The objective is to regenerate more than 70% of the mesic mixed forest within the designated patch back to a young, vegetative growth stage. Over several decades, plans are to develop much of the area into a multi-age mixed conifer forest using a variety of silvicultural techniques. The MN DNR stands will be managed along with 65 acres of USFS land. Stands are located within a designated Minnesota County Biological Site (MCBS) ranked as Moderate in biodiversity. This project is consistent with overall direction provided by the NE MN MFRC Landscape Committee and MN DNR's North Shore Sustainable Forest Resource Management Plan (SFRMP). Briefly:
- Move cover type composition closer to the range of cover type composition that historically occurred. Maintain/increase patch size.
- Provide a representation of growth stages that historically occurred.
- Maintain/increase species, age and structural diversity.
- Increase long lived conifers (white pine/white cedar) both as a cover type and a within stand component.
Past Management Practices:
Second growth forest in a relatively undisturbed condition. A few scattered, old white pine or white cedar stumps present. No recent management activity observed.
Present Conditions: (general composition and structure):
The forested area is dominated by large diameter paper birch and quaking aspen (9-15”dbh). Additional species present include balsam fir, white spruce, black spruce, red maple, and white cedar. Basal area range from 40-130 sq. ft/acre. The paper birch is considered a high-risk species due to its old age, top-dieback, and overall stand decline. Coarse woody debris (CWD) and snags are present in average numbers. The woody understory is comprised of moderate to heavy density shrub species along with many balsam fir seedlings. Only a few white pine seedlings are present per acre.
- Age of stands = 70-90 years old but varies considerably depending on the location within a stand and the topographical aspect.
- Growth Stage = mature
- Native Plant Community Classification = Fire Dependent Northern Mesic Mixed Forest.
- Timber Volumes = Quaking Aspen 12-20 cds/acre; Paper Birch-9-12 cds/acre; White Spruce 4 cds/acre; Balsam Fir 1.5 cds/acre; White Cedar 1 cds/acre; Red Maple 0.2 cds/acre; Black Spruce 0.5 cds/acre, and Black Ash 0.1 cds/acre.
- Woody Regeneration (0.1-5”dbh) = Balsam Fir 1180 trees/ac; White Spruce 30 trees/ac; White Cedar 20 trees/ac; Black Ash 15 trees/ac; Red Maple 5 trees/ac; White Pine 5 trees/ac (estimate).
Regenerate 70% of the patch to a young growth stage while maintaining and/or enhancing significant components of the mature growth stage and its unique characteristics. Overtime, manage the patch as a mixed conifer-hardwood stand while restoring and increasing the presence of white spruce, white pine, and white cedar tree species. Stand structural diversity will be promoted through a series of actions including retention and protection of:
- Scattered and clump reserve areas both outside and adjacent to the harvest areas. These will serve primarily as a source of desirable conifer seed.
- Within stand tree species diversity including mature paper birch, quaking aspen, spruce, white pine, white cedar, black ash, and red maple.
- Fine and coarse woody debris, snags, and downed logs.
- Native Plant Community (NPC) functionality including intact remnants of the herbaceous layer.
Cutting Blocks A and C: Shelterwood w/Reserves (see native plant community map below). Harvest and full tree skid paper birch and quaking aspen to a residual basal area of 40 sq. ft/acre. Block A requires full tree skidding of all harvested trees during dry summer or fall conditions to help reduce the woody shrub component, and to help scarify and expose the mineral soil layer. Block C will be frozen ground harvesting only. Reserve hardwood tree species including quaking aspen and paper birch will be evenly spaced throughout the harvest area. Additional reserve species include white and black spruce, white cedar, red maple, black ash, white pine, and all non-hazardous snags. Logging slash will be piled at designated landings. Some fine woody debris (FWD) will be re-distributed across the site. Logging operators are to leave at least 5 sound downed logs/acre (includes current CWD existing onsite). All temporary water drainages will be kept free of logging residue. Refer to MN DNR Forestry timber sale permit #B010605 for additional information.
Blocks B and D: Seed Tree w/Reserves (see native plant community map below). Harvest and full tree skid paper birch and quaking aspen . Full tree skidding during frozen ground harvest conditions only. Reserve hardwood species includes 6-12 (9-15”dbh) quaking aspen /acre (Block B) and 4-6 (9-15”dbh) quaking aspen or paper birch/acre (Block D) throughout the site. Additional reserve species includes white and black spruce, white cedar, red maple, black ash, white pine, and all non-hazardous snags. Logging slash will be piled at designated landings. Some FWD will be re-distributed across the site. Logging operators are to leave at least 5 sound downed lsound downed logs/acre (includes current CWD existing onsite). All temporary water drainages will be kept free of logging residue. Refer to MN DNR Forestry timber sale permit #B010605 for additional information.
Soon after harvest a regeneration check will be undertaken to assess conifer tree species presence and stocking. Depending on the regeneration check outcomes and further Manitou Collaborative discussions, mechanical site preparation methods will be evaluated. Planting contracts will also be initiated and crews will be instructed to plant conifer species in harvested areas. Specific planting spots will be located in scarified areas and in inclusions containing minimal hardwood sprouting. Other portions of the harvested site will focus on natural regeneration of hardwood species. All future planted white pine and white cedar will be protected from animal herbivory at least 5 years after planting. At year 3 post-harvest, the harvested area will be evaluated for a mechanical spot release of planted conifers. Over time, the developing stands will be scheduled for an intermediate harvest treatment.
Native Plant Communities and Harvest Treatments in the Manitou Patch – Ecological Silviculture Project (State Land)
Integrated Ecological and Silvicultural Considerations:
Get the right species on the right sites
The Manitou Collaborative certainly takes advantage of ecological principles and silvicultural interpretations. Recent fieldwork by MN DNR staff has confirmed the NPC class for all the vegetation within the patch project. Historical data indicates that fire dependent mesic forests were composed of a broader and more mixed composition of conifer species than currently present in the landscape. Although quaking aspen and paper birch tree species are suitable in this area, the desire for more long-lived conifers like white pine and white cedar is a specific outcome of this project. Tree species suitability tables indicate that white pine, white cedar, and white spruce all rank good to outstanding in their ability to compete with other plants in the community. Therefore, we are confident that these species can be restored and will grow into large, mature trees which will provide a multitude of benefits while contributing to future biological diversity and wood products.
Ensure future management options
Differing societal needs for wood products, potential climate change, and threats from invasive species and insects all play a role in the future composition of the forests. By incorporating the full range of silvicultural activities through the vegetation growth stages over time (young to old), we can have greater confidence in meeting the desire for a variety of tree species, habitat conditions, and stand structural conditions rather than simply growing forests to economic rotation and harvesting most or all of the trees in one activity. This suite of actions may include planting, site scarification, improvement techniques like hand release of target species, and intermediate harvests like thinning or variable density spacing. Specifically managing for diversity and complexity puts us in a better position to respond to change.
Treatment design must link biological legacy and treated area
Biological legacies usually involve reserving portions of intact forest or representations of uncommon growth stages. Forest ecologists define biological legacies “as the organisms, organic matter (including structures), and biologically created patterns that persist from the pre-disturbance ecosystem and influence recovery processes in the post-disturbance ecosystem (Frankin et al 2000). Legacies occur in varied form and densities, depending upon the nature of both the disturbance and the forest ecosystem.” Specific efforts went into determining and locating legacies within the patch project and we focused on leaving elements that provide significant purpose and function. These include spruce conifer seed trees, dying and standing dead trees, fine woody debris, advanced understory regeneration of desirable species, and clumped islands of older growth stages FDn43b2 plant community. Leaving these in a diverse spatial configuration throughout the site ensures the opportunity for herbaceous plants to re-colonize the site and maintains the ecological integrity of biological processes of growth and decay.
Don’t compromise ecological function
We should always ask fundamental questions about our treatment prescriptions.
- Will the sale design ensure adequate organic nutrient pools for regenerating trees?
- Will the sale design ensure adequate fine and coarse woody debris onsite
- Will the sale design, equipment, or season of operation negatively impact the site hydrology and riparian zone function?
- Will sale activity minimize the release of undesirable seed banks? Will post harvest activity promote invasion of exotic species?
Most of the paper birch type is overmature from a commercial standpoint. The trees have significant birch decline and top dieback and should be harversted to capture and further mortality. However, pure paper birch cover types lend themselves to shelterwood harvests and residual trees will provide high shade for planted and naturally regenerating understory conifers. Many of the resdual trees will die in the next 5-10 years thereby provide increasing light availability for understory-planted conifers, Some are dead already. Aspen is also mature and showing evidence of phellinus, hypoxylon canker, and top dieback. Mature balsam fir trees are scattered throughout and have likely seen periodic spruce budworm outbreaks in the past. All of the balsam fir will be harvested, but established and newly developing seedlings and saplings continue to pose budworm forest health concern. For more information about these species and related insect and disease issues click here.
Wildlife Habitat Considerations:
From a wildlife perspective, this is a course scale habitat management project which will provide more long term benefit to nongame species than the traditional game species. The initial harvest of the project site will improve moose browse conditions and long term may provide some thermal cover benefits particularly along the periphery and adjacent to suitable riparian habitats for moose. Refer to page 168 in Tomorrow’s Habitat: Forest-Upland Coniferous is listed as a Key Habitat for Species in Greatest Conservation Need within the North Shore Highlands Subsection. An active goshawk nest site is located in Block A. Nest protection has been incorporated into the sale design through DNR Forestry’s Supplemental Terms and Conditions Permit to Cut. In general, the silviculture prescriptions attempt to meet habitat preferred by the goshawk. Refer to the DNR Northern Goshawk Management Considerations. Lessard-Sams funding has been approved for planting blocks A and B. Funding for planting this site is just the initial phase. Long term, additional funding will be required for plant protection to reduce browse damage and selective hand release to maintain/improve within stand diversity. Forestry has done a good job of retaining reserve/legacy patches within the harvest area which adds to the diversity of the patch. Retaining a commercially viable production of forest products is also a desired outcome, particularly in regards to the trust fund status of this land.
Currently being overseen by Manitou Collaborative Partner- The Nature Conservancy... more on this as the trees grow and life unfolds.
The famous writer and itinerant outdoors conservationist Aldo Leopold sums up a poignant aspect of our work:
"Conservation is a state of harmony between men and land. By land is meant all of the things on, over, or in the earth. Harmony with land is like harmony with a friend; you cannot cherish his right hand and chop off his left. That is to say, you cannot love game and hate predators; you cannot conserve the waters and waste the ranges; you cannot build the forest and mine the farm. The land is one organism. Its parts, like our own parts, compete with each other and co-operate with each other. The competitions are as much a part of the inner workings as the co-operations. You can regulate them—cautiously—but not abolish them.
The outstanding scientific discovery of the twentieth century is not television, or radio, but rather the complexity of the land organism. Only those who know the most about it can appreciate how little we know about it. The last word in ignorance is the man who says of an animal or plant: "What good is it?" If the land mechanism as a whole is good, then every part is good, whether we understand it or not. If the biota, in the course of aeons, has built something we like but do not understand, then who but a fool would discard seemingly useless parts? To keep every cog and wheel is the first precaution of intelligent tinkering."
-Round River pp 145-146