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“I Want to Do a Selection Cut in a Northern Hardwood Stand, But How Do I Know How Much I Should Remove?”

1. Selection Cutting vs. Selective Cutting:
   It’s important to distinguish between “selection cutting” and “selective cutting”. Selection cutting is a legitimate silvicultural method, while selective cutting often refers to high-grading or diameter-limit cutting, which can be detrimental to forest health and long-term productivity .

2. Cutting Intensity and Residual Basal Area:

   • Remove approximately 30-40% of the stand’s basal area per harvest
   • Maintain a residual basal area of about 70-80 ft²/acre (16-18 m²/ha) after the harvest
   • Depending on site quality, you may need to maintain standing basal areas of sawtimber between 55-85 ft²/acre (240-370 m²/ha)

3. Tree Selection Criteria:

   • Remove trees based on their individual merits, considering factors such as:
     a) Growth rate
     b) Quality
     c) Surrounding competition
     d) Species
   • Focus on removing:
     a) Overmature individuals from older cohorts
     b) Poor quality or undesirable species from younger cohorts
     c) Trees that increase in value too slowly due to low quality or poor growth
     d) Trees that interfere with logging or the growth of better trees
     e) Trees likely to be lost before the next cutting cycle

4. Cutting Cycle:

   • Typically 10-20 years between harvests, depending on site productivity and management objectives
   • Some systems, like in the Adirondacks, use a 12-15 year cycle for beech-sugar maple stands

5. Spatial Pattern and Opening Sizes:

   • Use a combination of single-tree and small group selection:
     a) Single-tree selection for shade-tolerant species (e.g., sugar maple, beech)
     b) Small group openings (0.1-0.5 acres) to promote regeneration of mid-tolerant species (e.g., yellow birch)
   • For eastern hemlock, consider openings of 800-1000 ft² (80-100 m²)
   • Larger openings of 0.10-0.20 acres (400-800 m²) can promote yellow birch and, with ground scarification, trembling and bigtooth aspen

6. Stand Structure Goal:

   • Aim for a balanced uneven-aged structure with multiple age classes
   • Consider allocating growing space to overstory, midstory, and understory at a ratio of 3:2:1
   • Use the BDq method with a q-factor of 1.3-1.7 for 2-inch diameter classes

7. Species Composition Management:

   • In beech-dominated stands, control of understory beech may be necessary, potentially using herbicide application
   • To promote species diversity, consider:
     a) Opening the canopy
     b) Disturbing the groundstory to encourage shade-intolerant species
     c) Releasing smaller trees and shrubs

8. Regeneration and Site Preparation:

   • Ensure adequate advanced regeneration before harvesting
   • Consider site preparation techniques like scarification to promote desired species regeneration, especially for yellow birch

9. Wildlife Considerations:

   • Leave some standing dead trees and fallen logs for wildlife habitat
   • Consider retaining some larger trees or creating specific wildlife structures in harvest areas

10. Monitoring and Adaptive Management:

    • Regularly assess the stand’s response to treatments
    • Be prepared to adjust your approach based on regeneration success, species composition changes, and growth rate