The effects of selective harvesting on upland oak/hickory forests

David Dyson and Jessi Ouzts

Independent Study Project, Advent 2005

Introduction

Coarse woody debris Hickory seedlings Streamside management zone Compartment 10 – Severe basal damage due to skidding

Slash and tulip poplar seedlings

Residual trees

Sampling Methods

• Compartment 10 harvest:• 50 acres: • Logged in March, 2004• Total stumpage value: $15,700• Original BA = 114• Current BA = 80

• Compartment 6 harvest:• 29 acres• Logged February-April, 2005• Total stumpage value: $13,900• Original BA = 109• Current BA = 93

Objectives of this study: • To assess and compare residual damage of low-impact harvesting on two recently logged sites on the Domain.• To assess forest structure and dynamics after selective harvest.

Compartment 10

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BA (sq ft/ac)

SPA

• Used a grid overlaid on a topographic map to determine sampling points.• In the field, sampled within concentric 1/100th and 1/1000th acre plots • Determined slope/aspect, elevation, percent cover.• In 1/100th acre recorded dbh and damage level of trees over 2” dbh• In 1/1000th acre recorded all tree species less than 2” dbh

Results

Figure 3. Post harvest - diameter class distribution of all trees over 2” dbh

Key Points

• Logging at Compartment 6 left a more even diameter class distribution• Logging at Compartment 10 left a bell curve distribution, removing more trees in the higher and lower d-classes• Commercial species were found on both Compartment 10 and Compartment 6, primarily in the form of oaks.• Liriodendron tulipifera and Carya sp. were present in smaller numbers in the overstory.• Acer rubrum, Sassafras albidum, and Liriodendron tulipifera dominated the seedling class.• Damage percentage was determined by recording visible incidents of major basal and trunk damage (major = cut through bark and deep into heartwood). It was estimated at 22% for Compartment 10 and 17% for Compartment 6. • Economically, Compartment 10 (the larger of the two) brought in more board foot volume and more revenue.

Figure 4. Compartment 6 with sampling points.

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Compartment 6

Compartment 10

Post harvest counts of seedlings per acre by species showed Acer rubrum, Liriodendron tulipifera, Sassafras albidum in the highest numbers, with Quercus alba and Q. prinus found in slightly lower densities. A. rubrum and Quercus alba seedlings were more abundant in Compartment 6. L. tulipifera and Q. prinus were found more in Compartment 10. The post harvest tree stem count by species showed highest frequencies of Acer rubrum, Oxydendrum arboreum and Quercus alba in Compartment 10, while Nyssa sylvatica dominated the understory, predominantly in Compartment 6.

Compartment 6

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Quercus alba

Quercus coccinea

Quercus prinus

Quercus rubra

Quercus velutina

Carya sp.

Liriodendron tulipifera

Figure 7. Post-harvest diameter distribution of commercial species in Compartment 6.

Compartment 10

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Quercus alba

Quercus coccinea

Quercus prinus

Quercus rubra

Quercus velutina

Carya sp.

Liriodendron tulipifera

Figure 8. Post-harvest diameter distribution of commercial species in Compartment 10.

Figure 6. Compartment 10 with sampling points.

Figure 5. Map showing study sites on Sewanee Quad. Percent Residual Damage

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Compartment 10 Compartment 6

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Compartment 6

Figure 10. Harvesting data from Compartments 6 & 10.

Compartment 6

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Preharvest Postharvest % Removed

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Figure 9. Comparison of residual damage in Compartments 10 and 6.

Figure 2. Comparison of pre- to post-harvest BA and SPA on Compartment 6.

Figure 1. Comparison of pre- to post-harvest Basal Area (BA) and Stems per Acre (SPA) on Compartment 10.