Places We Protect

Chaumont Barrens Preserve

New York

A bee gathering nectar from a pink plant bud.
Chaumont Barrens A wide range of plants and wildlife make Chaumont Barrens their home. © Mathew Levine/TNC

Learn about one of the last and finest examples of alvar grasslands in the world.



PLEASE NOTE: Written permission is required to hunt on Conservancy lands.  To learn about our hunting program or to obtain permission to hunt, please visit our New York hunting information page.  

Chaumont Barrens Preserve is one of the last and finest examples of alvar grasslands in the world and is a link in the chain of North American alvars forming an arc from Jefferson County through Ontario, and all the way to northern Michigan. 

Alvar barrens are highly unique, prairie-like landscapes that rest atop a foundation of limestone bedrock. Scientists disagree on the reason there is so little soil on alvars—they may have been swept away during a cataclysmic drainage of glacial waters, or swallowed up by abundant fissures in the limestone.

In any case, what remains is a flat rocky terrain of grasslands, limestone woodlands, cedar forests, pavement barrens and globally rare plant communities. Alvar communities are adapted to survive extreme conditions: shallow soils, regular spring flooding, and summer drought.

This particular landscape developed after the last glacier retreated from this area some 10,000 years ago. Meltwater pummeled the landscape, cutting deep fissures into the bedrock. Over time, a striking, linear pattern of vegetation – including many prairie-type plants that are rare in New York – grew on this shallow soil. The resulting vegetation mosaic includes fossilized bedrock, deep fissures, rubbly moss gardens, and patches of woods, shrub savannas, and open grasslands.

The bedrock found throughout Chaumont Barrens is about 450 million years old. Scientists say that at that time, Chaumont was at the bottom of a shallow tropical sea near the equator.

If you look closely, you can find the remains of primitive marine animals, such as cephalopods, that lived in the ocean. These creatures were the top predator of the marine food chain and are related to the modern-day squid and octopus.



Closed to visitation during rifle season (Oct 24 - Dec 6).


Characterized by a mosaic of windswept vegetation, the Chaumont Barrens alvar landscape features rare and uncommon plants like prairie smoke, reindeer lichen and yellow-lady's slipper.

Explore our work in this region

The preserve is open daylight hours from early May until early fall. Opening and closing dates depend on the annual flooding cycle. For your safety and protection of the fragile soils and rare plants, please respect closure periods indicated on the parking lot sign. Chaumont Preserve has a self-guided, 1.7-mile trail that is uneven in spots. Use sturdy footwear and please watch your step!

Invasive Alert:
Pale swallow-wort is a dangerously aggressive alien plant that invades limestone-based soils throughout central and western New York. Get more detail on this weed and how it may threaten your own property.

Chaumont Barrens supports a wide range of wildlife, including:

  • porcupine
  • coyote
  • prairie warbler
  • clay-colored sparrow
  • scarlet tanager
  • golden-winged warbler
  • upland sandpiper
  • eastern towhee
  • whip-poor-will
  • common yellowthroat
  • black and white warbler
  • cedar waxwing

In late May, visitors can enjoy a diverse succession of native wildflowers in bloom, especially prairie smoke, which can be seen nowhere else in the northeast. Many other plants also make Chaumont Barrens their home:

  • prairie smoke
  • blue phlox
  • bloodroot
  • balsam ragwort
  • yellow lady's slipper
  • early buttercup
  • reindeer lichen
  • white cedar
  • white spruce
  • white pine

Chaumont Barrens is located in Jefferson, New York, within the Alvar Barrens and Grasslands Priority Conservation Landscape.

Find More Places We Protect

The Nature Conservancy owns nearly 1,500 preserves covering more than 2.5 million acres across all 50 states. These lands protect wildlife and natural systems, serve as living laboratories for innovative science and connect people to the natural world.

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