Project Area
Surry Mountain Preserve is located in southwestern New Hampshire, approximately 4 miles north of the City of Keene. It sits on a north-south running ridge within a hilly and forested landscape. Seven headwater streams originate on the Preserve and flow into the Ashuelot River, a major tributary to the Connecticut River. The watershed of the Ashuelot includes some of the least fragmented forests in southwestern NH, and the Preserve is part of a contiguous block of 50,000 acres of protected land representing a critical resilient “climate flow zone” as identified by TNC’s Resilient and Connected Landscapes analysis (2016). The Preserve is 1,324 acres, of which 50% (675 acres) has been identified as a Wildlife Management Area (WMA). TNC and NH Fish and Game Department have co-developed a forest management plan for the WMA that promotes resilience of the existing high-quality forests and wildlife habitat. Forest stands within the WMA are mature with many large trees and old forest features naturally developing. Tree species include red oak, white pine, American beech, and eastern hemlock, with pockets of richer soils supporting higher species diversity including sugar maple, basswood, and white ash. Focal wildlife species on the Preserve are primarily those of mature forests and riparian areas including many state-listed species of bats, northern goshawk, scarlet tanager, veery, eastern brook trout, wood turtle, bear, and moose.
Management Goals
Maintain and enhance the compositional and structural diversity of forested habitats on the Preserve to support the focal wildlife species and other Species of Greatest Conservation Need (SCGN).
- Increase/maintain structural diversity to create browse, pollinator areas, and young forest structure.
- Monitor to increase our understanding of focal wildlife species use of the Preserve and the response of wildlife to changes in management.
- Maintain tree cover, possibly including a replacement for Eastern hemlock, within buffer areas of small stream to minimize erosion and reduce summer stream temperatures.
- Manage for high overall tree species and functional diversity to increase the amount of local species adapted to future climate conditions and disturbance compared to the current condition.
Maintain and accelerate healthy development of old forest characteristics.
- Protect interior forest conditions, and areas with well-developed old forest characteristics (e.g., designate reserve areas) of the forest for Wildlife Action Plan focal species.
- Increase carbon storage through the accelerated development of old forest structure and tending of large legacy trees. Promote resilient forest carbon stocks.
- Increase snag and downed wood abundance and diversity.
Manage regeneration to ensure future forest maintains high quality forest habitats for Wildlife Action Plan focal species long-term.
- Increase oak regeneration, and other healthy mast-producing tree species and reduce prevalence of regenerating diseased beech.
Demonstrate techniques for managing for forest resilience and transition in the face of uncertain climate futures.
- Set up trial areas to test and monitor management actions and report out on results.
Climate Change Impacts
For this project, the most important anticipated climate change impacts include:
The growing season in New England is generally expected to increase by 20 days or more by the end of the century, due to fewer days with a minimum temperature below 32°F.
Forest vegetation may face increased risk of moisture deficit and drought during the growing season, especially those growing on droughty soils or southern slopes.
Certain insect pests and pathogens (e.g., hemlock wooly adelgid, beech leaf disease, beech bark disease, hemlock looper, emerald ash borer) will increase in occurrence or become more damaging in New England.
Warmer temperatures and altered precipitation in the region will interact to change soil moisture patterns throughout the year, with the potential for both wetter and drier conditions depending on the location and season.
The winter season will be shorter and milder across New England and northern New York, with less precipitation falling as snow and reduced snow cover and depth.
Conditions affecting tree regeneration and recruitment will change and cause shifts in forest composition across the landscape.
Intense precipitation events will continue to become more frequent in the region.
Challenges and Opportunities
Climate change will present challenges and opportunities for accomplishing the management objectives of this project, including:
Challenges
Changing forest compositional change can have cascading effects on many focal wildlife species. For example, loss of keystone tree species like hemlock will affect brook trout and bird species needing more intact forest cover.
Disease and pests outbreaks can cause chronic declines in forest species (e.g. beech, hemlock, oak) resulting in reduced productivity and reduced carbon storage and sequestration.
Tree species regeneration may be challenged if periods of drought become more frequent and severe. This is especially a concern if the species is a food source for wildlife (e.g., oak).
Longer growing seasons and milder winters may contribute to changes in herbivore populations that can have substantial effects on regeneration success and forest composition
Hemlock, a keystone riparian species, is sensitive to soil moisture shifts (drought), susceptible to mortality by pests, and is projected to have limited habitat suitability by end of century.
The possible presence of federally-listed bat species limits forest harvest operations to months outside of the optimal time to regenerate oak.
Large stand-replacing disturbances (e.g., windstorms, insect outbreaks) are unpredictable and can cause widespread mortality, disrupting old forest conditions and associated carbon stocks.
More frequent and intense precipitation events will increase risk of soil erosion, particularly of the headwater streambanks.
Higher temperatures in the summer may contribute to drought stress to amphibians in the forest, and aquatic organisms in headwaters streams (e.g., eastern brook trout).
Increasing deer herbivory pressure poses a challenge to the survival and growth of tree seedlings.
Opportunities
The contiguous forests surrounding the preserve present opportunities for plant and wildlife species movement, adjustment, and new species recruitment and migration.
More frequent extreme disturbance events could increase diversity of age classes and forest structure over time (downed wood, snags, tip ups).
A longer growing season may support greater carbon storage and sequestration on site, especially given the high-quality soils in some areas.
Currently, the forest has high species diversity and opportunities to favor on-site future-adapted species.
The site will become more suitable for expanding southern plant and wildlife species, including other mast tree species (oak, hickory, chestnut).
Soil moisture deficits may increase operability for oak scarification in late summer.
Less snow due to milder winters may may increase wildlife movement for some species and reduce the importance of hemlock for providing winter cover.
Wildlife species on site that are adapted to warmer, drier conditions may cope with changing conditions better than others over time.
Adaptation Actions
Project participants used the Adaptation Workbook to develop several adaptation actions for this project, including:
Area/Topic
Approach
Tactics
Wildlife habitat (Stands 4, 5, & 6)
8.1. Manage for plant species diversity and complexity
8.4. Manage and create suitable microhabitats and microclimates
8.4. Manage and create suitable microhabitats and microclimates
Girdle and/or cut and leave downed wood to create structure, roost sites, and microhabitats.
Create small canopy openings to increase structural diversity, wildlife browse, pollinator food sources, and guide regeneration to ensure future food sources for focal wildlife species.
Conduct enhancement plantings in larger patch cuts to boost pollinator food sources.
Riparian areas (Stand 3)
Place strategic wood additions in headwater streams to slow water during large storm events and enhance instream habitat for fish and other aquatic species, including eastern brook trout, against drought stress.
Promote or plant surrogate to hemlock in select areas near streams to maintain shading and bank stability if/when hemlock declines.
Thin within existing stands of hemlock to increase vigor and resistance to hemlock wooly adelgid.
Old forest characteristics (Stands 5 & 6)
Designate reserve areas to protect legacy trees and other unique old-forest features.
Select trees as long-term legacies, and protect existing legacy trees.
Thin to release some large trees to develop into future legacies.
Recruit diverse forms of dead and downed woody material (8-10 snags and downed wood/acre >20” DBH).
Regeneration (Stands 4, 5 & 6)
3.1. Alter forest structure or composition to reduce risk or severity of wildfire.
9.1. Favor or restore native species that are expected to be adapted to future conditions.
9.1. Favor or restore native species that are expected to be adapted to future conditions.
Create large gaps (2-5 acres) with desirable seed tree retention to promote more oak and greater diversity in tree regeneration including birch, maple, cherry, and pine. (Stand 4)
Create small canopy openings (0.5-2.0 acres) with variable retention to regenerate desirable and future adapted species, and develop a healthy second and third cohort to build resilience and multiple pathways to absorb disturbance. (Stands 5 & 6)
Within canopy openings, enrichment planting of mast-producing tree species projected to grow well under future site conditions, including some more southern species of hickory and oak not currently known from the site.
1.4. Reduce competition for moisture, nutrients, and light.
9.5. Disfavor species that are distinctly maladapted.
9.5. Disfavor species that are distinctly maladapted.
Avoid harvesting in beech-dominated areas to limit resprouting and regeneration of beech due to prevalence of beech bark disease and beech leaf disease. (Stand 4)
Monitoring
A monitoring plan was written and is being implemented to establish baseline conditions and track the impacts of the harvest on the forest and wildlife community. Components of the monitoring plan include:
Year-round wildlife monitoring to document presence/absence of wildlife species within each of the three treatment types (patch, thin, reserve) using game cameras.
Annual audio monitoring of birds for a 10-day period during breeding season, and for bats in June-July using the USFWS protocol, within each of the three treatment types using audio recorders.
Revisiting permanent forest monitoring plots within each of the three treatment types (patch, thin, reserve) to survey success of natural regeneration (species, % survival, herbivory, and invasive species) every 3 years.
Documenting the height, health, vigor, and crown cover of Legacy trees (large and structurally complex trees) in the harvest area (year 1, 3, 5, and 10).
Repeating forest inventory 10 years post-harvest to capture changes in abundance of snags and downed woody material, and regeneration (composition and abundance).
Tracking stream flow and temperature using HOBO dataloggers.
Conducting benthic macroinvertebrate and Eastern brook trout counts pre- and post- strategic wood additions in Sturdevant Brook.