Sustainable timber harvest on the Black Hills National Forest

Photo Credit

USDA photo by Alexis Neukirch

Ponderosa pine seedlings in a managed study site in the Black Hills Experimental Forest

Land use and natural disturbances constitute the fabric of the Black Hills forests. Over the last two decades (2000-2020), multiple disturbances (e.g., mountain pine beetle epidemic, wildfire) have changed forest characteristics of the Black Hills.

Following several years of intensified and accelerated Forest Inventory & Analysis Program sampling in the Black Hills, Forest Service scientists assessed trends in standing volume, growth, mortality, and the implications of various harvest levels to better understand sustainable harvest options.

Sixty scenarios were evaluated, including a range of volume mortality rates, volume gross growth rates, and four harvest levels. The report provides scenario outcomes after five years and 20 years, and through an 80-year period.

Key Findings

• The combination of recent mountain pine beetle-caused mortality and harvest levels (181,000 CCF/year) have resulted in a negative forest growth increment.
• The current live sawtimber volume (5,995,428 CCF) does not support a long-term sustainable timber supply at the current allowable sale quantity of 181,000 CCF/year, as defined in the Black Hills National Forest Plan under a wide range of scenarios considering growth and mortality rates.
• Depending on growth and mortality rates evaluated, 23 of the 60 scenarios would be considered a sustainable rate of harvest over an 80-year period. Of the 23 sustainable scenarios, five allowed 126,700 CCF/year as the maximum harvest level for sawtimber.
• Over the next several decades, if mortality rates remain below 1.04%, harvest levels of 72,400 and 90,500 CCF/year appear to be sustainable if all suitable timberlands are available for harvest.