underbrush

2. Low-growing plants and small trees that grow beneath the taller trees of a forest.

Sunlight rarely reaches the underbrush on the forest floor.

3. A dense, tangled mass of shrubs and vines that is hard to walk through.

We had to push through the underbrush to reach the river.

4. Anything that is small, low, and crowded together, like a messy pile of plants.

The garden's underbrush was full of weeds and fallen leaves.