• Start-up
  • Planning
  • Action
  • Evaluation

Adaptation tactics for this project include identifying best methods to release existing red spruce, and maintain the habitat for future seed-bearing trees and regeneration.

The main goals of this project are aimed at restoring historical red spruce-dominated conifer-hemlock forest composition and increasing conifer cover on public lands in Maryland and West Virginia. To accomplish these goals, this project is focusing on red spruce release within TNC preserves in western Maryland. Staff from TNC used this project to complete the adaptation workbook during an online course, and identified some adaptation actions that can be incorporated into future experiments on red spruce, and can help provide refugia for red spruce in the future, while increasing site resistance to climate change impacts.

Project Area

TNC Finzel Preserve boundaries in western Maryland
TNC's Finzel Preserve is located in western Maryland, close to West Virginia. The ecosystem targeted for increasing red spruce cover typically occurs on gentle to steep slopes, and on soils that range from slightly acidic to very acidic, with varying amounts of nutrients, depending on landscape position and parent material. Common species that typically occur on these sites include sugar maple, American basswood, American beech, white ash, black cherry, yellow birch, sweet birch, red maple, eastern hemlock, red spruce, and tulip tree. Originally our only project area was going to be Cranesville Swamp, but at a recent site visit we found red spruce planted over 15 years ago being suppressed by other species. The suppressed spruce are barely 3 ft. tall, so release should reveal a much more dramatic impact on growth rate. Finzel also lies in TNC’s prioritized connected landscape which makes it a better demonstration project than Cranesville, and potentially becoming part of the action plan for connecting landscapes in MD to WV and PA.

Management Goals

Field staff surround a small red spruce tree
  • Go through mechanical girdling training with WV TNC staff 
  • Accelerate the red spruce restoration and regeneration by multiple decades by removing competing hardwoods 
  • Record data on hardwood species removed as well as the quantity. Mark GPS points on target red spruce and take height, growth, and DBH measurements so that the effect of release can be determined in the future. 

Climate Change Impacts

Many dominant species within the Appalachian (hemlock)/northern hardwood forest are at risk of decline, especially under the higher emissions scenario. Suitable habitat and conditions for red spruce are expected to decline in the project area based on these key climate change impacts:
Mean annual temperatures in the Central Appalachians will increase between nearly 2 and 8 °F by the end of the century, with more warming during summer and fall than winter and spring.
Winter snowpack in the Central Appalachians will be reduced from 20-50% by the end of the century.
The Central Appalachians growing season will increase by 30 to 70 days by the end of the century
Soil moisture patterns will change in the Central Appalachians, with drier soil conditions later in the growing season

Challenges and Opportunities

Climate change will present challenges and opportunities for accomplishing the management objectives of this project, including:


Increasing temperatures, especially during summer months, and an extended growing season will place more stress on boreal species and potentially favor invasive species.
Higher minimum temperatures in the winter and more winter precipitation falling as rain will decrease snowpack, resulting in less optimal conditions for red spruce germination and increased chances of herbivory and damage from extreme cold.
Decreases in precipitation during summer and fall months will increase drought and soil moisture stress, which is especially damaging to seedling establishment and survival.
As multiple stress factors interact, invasive species, insects, and diseases could become more damaging.


Variations in slope and topography of the project area could provide frost pockets, which would be potential refugia for northern species.
Some studies have shown that a decrease in local pollution is allowing spruce to take advantage of an excess of carbon dioxide to accelerate their growth rates.

Adaptation Actions

The Nature Conservancy Staff used the Adaptation Workbook to develop several adaptation actions for this project, including:

Maintain or create refugia
Use Chesapeake Conservation Corps mini-grant to experiment with a variety of mechanical girdling methods for hardwoods that are suppressing red spruce
Release individual red spruce trees from hardwood competition via girdling the neighboring overtopping hardwood trees. Focus on the species that are not included in the management goals and only remove neighboring trees that are necessary for release


Project participants identified several monitoring items that could help inform future management, including:
growth of released red spruce (cm/yr, height and dbh)
foliar cover (%) densiometer
red spruce cone production (#/3 yrs) of released red spruce
hardwoods girdled (# and species)

Next Steps

This project is still in the planning phase, and likely will not be implemented (partially, or in its entirety) until further planning occurs.

Learn More

To learn more about this project, contact


Forest threats
Insect pests