The Restoration Bargain · Episode 11 of 13 · 24 min
The Ground Beneath
Thin the forest, restore the deep-rooted native understory, move carbon into soil where fire cannot reach it, and close the loop with biochar. It is a beautiful idea, and most of it does not survive measurement. Soil carbon is a minority of ecosystem carbon in ponderosa pine, glomalin's role is overstated, and thinning does not raise soil carbon. The episode ends on what holds up: reduced smoke, deep-rooted grasses, and thin-plus-burn.
Who's who
- Sara F. WrightUSDA soil scientist who described glomalin in the 1990s
- Beverly Law+1 more episodeOregon State researcher whose Metolius ponderosa work inventories where forest carbon sits
- John Campbell+2 more episodesCo-author of the 2012 paper on carbon removed versus protected
- Mark Harmon+1 more episodeCo-author of the 2012 carbon ledger paper
- Matthew Hurteau+2 more episodesEcologist whose modeling gave the thin-and-burn crossover year
- Deborah Page-DumroeseForest Service soil scientist behind biochar and air-curtain burner trials
- Paul Hessburg+1 more episodeCo-author of a 2025 paper arguing western forest carbon capacity is exceeded
- Werner KurzBuilt Canada's national forest carbon budget model; co-author with Hessburg
Where it happens
- Metolius, OregonPonderosa chronosequence supplying ecosystem-carbon fractions
- Blodgett Forest, CaliforniaSite of a twenty-year replicated thinning experiment
- Lubrecht Experimental Forest, MontanaSite of an eleven-year replicated experiment
- Colville Valley and Spokane airshed, WashingtonInversion-prone region where the smoke argument matters
Timeline
- 1968Study measures snowbrush nitrogen fixation across twelve Oregon stands
- Late 1990sSara Wright describes glomalin
- 2012Campbell, Harmon, and Mitchell publish the carbon-removed-versus-protected ratio
- 2015-2016Hurteau models thin-and-burn overtaking the control at year 40 under 2 percent annual fire probability
- 2021Review defines glomalin as an unidentified putative gene product
- 2024Twenty-year Northern Rockies results favor thin-plus-burn for retaining ponderosa pine
Still debated
Whether thinning ever repays its carbon cost depends almost entirely on assumed wildfire probability. The Hessburg and Kurz carrying-capacity argument is a live, contested position, and nitrogen fixation by snowbrush is unresolved by a factor of five to fifty.
