Fire on the Ridge: The ‘Inimim Pile Burn

Waiting for the window

Prescribed fire is mostly waiting. It's checking the forecast, checking it again, watching the fuel moisture numbers tick up and down, and being ready to go — or not go — at short notice.

The ‘Inimim pile burn was first floated for a window between March 11 and March 22, with March 16 as the tentative primary day. That window closed without firing a single pile. "Just wanted to clarify with everyone we will NOTbe burning on Monday 3/16," Jorge Pacheco of the U.S. Wildland Fire Service wrote on March 13. "Duane and I will continue to monitor for a good burn window and will notify you all when we settle on a date."

The next target was Tuesday, March 31 at 0800, with a plan to meet at the intersection of Shady Grove and Jackass Flats Road. The forecast — mostly cloudy, rain likely in the morning, rain likely in the afternoon, a max temperature around 60°F, humidity in the high 60s, and light south winds — put every prescription parameter comfortably in the "cool" end of the acceptable range. A wet day is a good day for pile burning. The crew committed.

The work itself had been years in the making. The ‘Inimim Forest — roughly 2,000 acres of BLM-managed public land interwoven with private parcels along the San Juan Ridge — has been the subject of a long, active restoration partnership between the BLM Mother Lode Field Office and Yuba Watershed Institute. The machine piles scheduled for ignition had been built over the past few months as part of Phase 3 of the ongoing 'Inimim Forest Restoration Project, an SNC-funded effort to thin overstocked stands, reduce the hazardous fuel load, and return the forest to a more fire-resilient condition. Thinning without burning only gets you halfway there; the piles had to come down.

What it accomplished — and what's next

Across two days, the ‘Inimim pile burn put fire on roughly 250–260 acres and consumed at least 85% of the machine-piled biomass built up from Phase 3 thinning. The material that remains is almost entirely in the 8-inch-plus, 10,000-hour fuel category — big-diameter logs that are difficult to consume in a single burn and will continue to decompose naturally on the forest floor.

A week after the burn, Duane Fields walked the units with supervising forester Katherine Benedict (TÜV SÜD America) and identified four piles— one in each unit — that didn't burn down as thoroughly as hoped. Rather than force those piles now, Terra Fuego proposed returning in the fall of 2026 to consolidate and re-burn them. A portion of the contract value is being held back until that cleanup is complete.

Pile burning is one piece of a bigger restoration arc in the ‘Inimim Forest. With the 2026 piles on the ground, attention turns toward the remaining Phase 3 implementation work, continued monitoring of the treated stands, and — eventually — reintroducing broadcast prescribed fire under conditions that mimic the low-intensity burns that shaped this forest for thousands of years.

Thanks to the crew

Prescribed fire is a team sport, and this one took more coordination than you can see in any single photo. Gratitude is owed to:

• Terra Fuego Resource Foundation — Bill Jacks, Duane Fields (burn boss), Jason Davis, and the full ignition and holding crew
• BLM Mother Lode Field Office and U.S. Wildland Fire Service — Jorge Pacheco, Burns Brimhall, David Brinsfield, Jeffrey Horn, Roger Brown, and Beth Brenneman
• TÜV SÜD America Forestry Consulting — Katherine Benedict (Registered Professional Forester), and Ben Miller
• Northern Sierra Air Quality Management District — for smoke coordination
• The Jackass Flats and North Columbia neighbors — who drove out to take pictures, waved as they passed, and made clear that this kind of work is welcome in this community

Funding for the Phase 3 work that built these piles comes from the Sierra Nevada Conservancy (Agreement #1507).