The State of the Trees · Episode 9 of 13 · 19 min
The Eastern Woods: The Crisis Under a Healthy Canopy
The eastern forest looks the healthiest of all, a full green canopy from the Ozarks to Maine, and that canopy hides the deepest crisis. Oaks and hickories dominate overhead but cannot regenerate in shade, while red maple inherits the understory and remakes the future forest. Meanwhile ash is all but gone to the emerald ash borer, hemlock is collapsing, beech is hit by two diseases and sugar maple's range slides north.
Who's who
- Gregory NowackiResearcher who developed the concept of mesophication
- Marc AbramsResearcher who developed the concept of mesophication
Where it happens
- Ozark PlateauWestern edge of the eastern deciduous forest
- Maine coastNortheastern edge of the continuous green canopy
- Detroit, Michigan+7 more episodesWhere the emerald ash borer was detected in 2002
- Lake County, OhioWhere beech leaf disease was first observed in 2012
Timeline
- 1930sOrganized fire suppression takes hold across the eastern United States
- Mid-20th centuryRed maple and shade-tolerant species build up in understories
- 2002Emerald ash borer detected near Detroit
- 2012Beech leaf disease first observed in Ohio
Still debated
Whether oaks are winners or losers is held in tension: they dominate the canopy and suit a warming climate, yet are demographically failing to regenerate under the shade of red maple.