Acidic Boulderfield (Central Appalachian)

The Acidic Boulderfield, with its boulder-covered steep slopes, is not a welcoming environment for plants. The soil is sparse, acidic, and infertile. But a variety of species of lichen grow on the surface of the rocks. (There is more than one type of Acidic Boulderfield; this one occurs in the Central Appalachian mountains.)

The Acidic Boulderfield occurs on exposed, steep slopes of quartzite and sandstone boulders with little or no soil.

The range map shows the states in which this natural community has been documented.

More About This Natural Community

The Acidic Boulderfield natural community consists of lichen-covered boulders on steep slopes. A lichen is an organism that consist of an alga and a fungus living together symbiotically. Toadskin lichen and Pennsylvania toadskin lichen are usually abundant in this natural community.

The boulders are quartz-rich rocks that contain few base elements, such as calcium or magnesium, to act as nutrients for plants. For that reason, what little soil exists here is typically infertile and quite acidic.

Along the edges of the natural community you may find some Virginia creeper or stunted sweet birch or blueberries.

For a more in-depth look at this community, click on a link under “Where to Explore It.”

Look for It in These National Parks

  • Appalachian Trail (Central Appalachians)
  • Catoctin Mountain Park
  • Delaware Water Gap National Recreation Area
  • George Washington & Jefferson National Forests
  • Harpers Ferry National Historical Park
  • Shenandoah National Park

Conservation Status

How vulnerable is a natural community? Is it at risk of elimination? Learn about conservation status.

Global Conservation Status: 
G5 – Secure


Official names reduce confusion by providing a common language for talking about natural communities. Why so many names?

Common Name: 
Acidic Boulderfield (Central Appalachian)
Scientific Name Translated: 
(Toadskin Lichen, Pennsylvania Toadskin Lichen) - Golden Moonglow Lichen - Culberson's Black-parmelia Nonvascular Vegetation
Classification Code: