Pando, the Utah aspen clone of about 47,000 stems, and Oregon's humongous fungus are among the largest living things on Earth, and forests and their fungi hold vast, under-counted carbon. The famous size and age figures are estimates, and the episode flags that uncertainty. Wonder meets the carbon ledger.
Who's who
- Paul RogersUtah State University ecologist and leading voice on Pando's decline
- Catherine ParksU.S. Forest Service scientist who documented the Oregon Armillaria as one individual
- Heidi HawkinsLead author of the 2023 mycorrhizal carbon study
- E. Toby Kiers+1 more episodeEvolutionary biologist; senior author of the 2023 study and co-founder of SPUN
Where it happens
- Fishlake National Forest, UtahHome of Pando, the quaking aspen clone
- Malheur National Forest, OregonSite of the humongous Armillaria fungus
- Blue Mountains, OregonRange containing the humongous fungus
Timeline
- c. 2000-2003Parks and colleagues document the Malheur Armillaria as a single genetic individual
- 2018Rogers and McAvoy show Pando is failing to regenerate, largely from overbrowsing
- 2023Hawkins et al. estimate a very large annual plant-to-fungus carbon flux
- 2024-2025New Pando age modeling and expanded fencing; cattle grazing on the site ends
Still debated
Pando's age is unsettled, with estimates from about 9,000 years to tens of thousands. Which organism is largest depends on whether size means mass, area or clonal extent, and how much fungal carbon is durably stored is open.
