Identifying High Conservation Value bottomland forests

Protecting special forest types

In late 2015, the Endowment conducted a consultation process to identify four priority bottomland hardwood forest types in North Carolina and Virginia: cypress-tupelo swamps, Atlantic white cedar stands, low pocosins, and Carolina bays. These forest types provide a wide range of environmental and economic benefits and are geographically unique to this region. Enviva does not accept wood from these High Conservation Value (HCV) areas. (For more information, visit the Enviva Forest Conservation Fund.)

Evaluating critical factors

For forest health

However, most of the region’s bottomland forests do not fall into these four priority categories and have been managed as working forests for generations. Moreover, many forests in the Southeast have been damaged by storms and high winds or previously harvested using methods that degraded the stand’s structure and health. In many cases, harvesting the forest in the proper manner is the best management technique to improve the forest’s resiliency. We provide a market for this low-grade material that incentivizes landowners to make good forest health management decisions. Enviva’s HCV Approval Process provides a framework for us to evaluate the health and attributes of potential tracts and determine if we will accept wood from a bottomland hardwood tract.

HCV approval process

First-level assessment

This program involves a two-stage process that must be completed prior to purchasing any wood from the landowner.

 

When a supplier wants to sell wood to Enviva from a potential harvest site, Enviva’s foresters conduct a preliminary assessment to determine if the forest meets a set of specific criteria that indicate that the site might be a HCV forest. The preliminary assessment indicators for each priority forest type are presented in the table below.

 

Cypress-Tupelo Carolina Bay Low Pocosins Atlantic White Cedar
>10% volume cypress Aerial photo shows landscape depression Pond pine overstory >50 years old >10% Atlantic white cedar
Seasonally flooded, semi-permanently flooded, or permanently flooded soils Seasonally saturated, seasonally flooded, or semi-permanently flooded soils Seasonally saturated, seasonally flooded, or semi-permanently flooded soils Seasonally saturated, seasonally flooded, or semi-permanently flooded soils
Bottomland hardwood forest >80 years old Longleaf pine forest >80 years old Flat top; stunted pond pine is dominant species –
Bottomland hardwood forest >120 acre clearcut Flat top; stunted pond pine is dominant species – –

HCV approval process

Second-level assessment

If any of these preliminary assessment criteria are met, then further investigation is required, most often involving a site visit to determine if the site is truly HCV or a typical bottomland hardwood working forest.

 

During this second-level assessment, Enviva foresters collect physical attribute data on the forest’s structure, health, and hydrology. Specific examples of tract data include the following:

  • Evidence of stand health
  • Examples of adjacent regeneration
  • Availability of seed source for regeneration
  • Tree stocking levels
  • Insect and disease damage
  • Stand hydrology characteristics
When tracts are determined as non-HCV and where harvest is appropriate, Enviva works with suppliers to develop an individualized harvest technique that is most suitable for the site. We accept wood from a tract only when we determine that the forest is indeed a working forest that is likely to regenerate successfully after harvest with the desired species composition. Once approval has been completed, Enviva will perform on-site visits during harvest to monitor supplier performance and ensure the harvest technique is being properly executed.
 
All documentation throughout the assessment and harvest process is stored for historical reference.