understory

Like much of the American West, Yosemite’s forests evolved to endure periodic blazes, which cleared clutter from the understory and opened up space for new trees to grow.
Postcards from Earth’s climate futures|Aaron Steckelberg, Sarah Kaplan, Brady Dennis, Yutao Chen|February 28, 2022|Washington Post
They decided to excavate the understory of the conflict—to figure out what it was really about–which required asking different questions and truly listening.
We Need More 'Good Conflict' in Our Lives. Here's How It Works|Amanda Ripley|April 17, 2021|Time
“There’s no understory vegetation left, let alone any leaf litter suspended in it, so that species is really hanging in the balance,” says Marsh.
A year after Australia’s wildfires, extinction threatens hundreds of species|John Pickrell|March 9, 2021|Science News
Trees were small in this part of the woods, with a well developed understory thicket of coralberry and sumac.
Ecological Observations on the Woodrat, Neotoma floridana|Henry S. Fitch

An almost continuous canopy of foliage has developed, shading the understory and thinning it by killing shrubs and saplings.
Ecological Observations on the Woodrat, Neotoma floridana|Henry S. Fitch
Purshia tridentata (bitterbrush) is the understory codominant.
Comparative Ecology of Pinyon Mice and Deer Mice in Mesa Verde National Park, Colorado|Charles L. Douglas
Vegetation was pinyon-juniper woodland with an understory of mixed shrubs.
Comparative Ecology of Pinyon Mice and Deer Mice in Mesa Verde National Park, Colorado|Charles L. Douglas
A relatively pure understory of Poa fendleriana (muttongrass), is typical of such woodland on the middle parts of the mesas.
Comparative Ecology of Pinyon Mice and Deer Mice in Mesa Verde National Park, Colorado|Charles L. Douglas

Origin of understory