This post includes ideas and an excerpt of analysis from the Q2 2026 Forisk Research Quarterly.

Introduction

The Washington Forest Practices Board approved a new rule to expand stream buffers on non-fish bearing perennial streams (Type Np) on November 12, 2025. The rule expands buffers on private and state-owned timberland from 50 feet to 75 feet in width and requires a buffer on the full length of the stream when previously only 50% required a buffer. The Forest Practices Board approved the change to protect stream temperatures from warming, but landowners argue that the Board approved the rule without demonstrating a scientific need for the change through a reinterpretation of the standards. The Washington Forest Protection Association and Washington Farm Forestry Association filed a legal challenge asking the court to vacate the rule or send it back to the Board for reconsideration. The new Np rule goes into effect on August 31, 2026, unless the legal challenge is successful.

Impact on Harvestable Timber

An economic assessment performed by Jeffrey Comnick and Luke Rogers at the University of Washington estimated the impact of the Np rule on harvestable standing timber volume on private timberlands in western Washington. They found that impacts ranged from a 1% loss to 12% loss in harvestable volume. Impacts were greatest in Pacific and Wahkiakum counties in southwest Washington. Most counties had 3% to 4% losses in harvestable volume due to the Np rule.

Future Research

Forisk will incorporate impacts from the Np rule in timber supply forecasts later this year in the Forisk Research Quarterly.

For additional figures and notes on this topic, see the Pacific Northwest chapter in the Q2 2026 Forisk Research Quarterly (to be published May 2026). To learn more about the Forisk Research Quarterly (FRQ), click here or email Nick DiLuzio at ndiluzio@forisk.com.