Places We Protect

Grass Bay Preserve


An orange and purple sunset over the Lake Huron shoreline at Grass Bay Preserve in Michigan.
Grass Bay Preserve Watch the sun set over Lake Huron's stunning shoreline. © Jason Whalen/Big Foot Media

Grass Bay Preserve is a paradise for wildflowers and neotropical migrating birds along two miles of Lake Huron shoreline.



Three species of wildflowers are found nowhere on Earth but along the Great Lakes and they all thrive at Grass Bay—the diminutive dwarf lake iris (blooming in purple or white), Pitcher’s thistle and Houghton’s goldenrod. The songs of such neotropical migrants as the black-throated blue warbler and the prairie warbler can be heard throughout the diverse landscape of shoreline, open dunes, interdunal wetlands, coniferous swamps and forests. It is home to 12 of Michigan’s 13 coniferous species and over 300 plant species.


Limited Access

There is no on-site parking lot available at this location.


Wildflowers, migrating birds, Lake Huron shoreline, open dunes, interdunal wetlands, coniferous swamps and forests.


834 acres

Explore our work in Michigan

Grass Bay Preserve (3:12) Grass Bay Preserve is a paradise for wildflowers found only along the Great Lakes. While the species is rare, you may even spot the elusive Dwarf Lake Iris.

Wildflowers at Grass Bay Preserve

The preserve is home to more than 300 species of plants. Throughout the year, you'll see wildflowers blanket the forest floor and line the edges of wetlands.

Walk Through the Wildflowers
A close up of the thin petals of a pitcher's thistle bloom.
Carnivorous Bladderwort grows along Presque Isle shoreline.
The crimson leaves of the pitcher plant grow from the ground.
Pitcher's thistle grows along the sandy shore of a lake.
A macro photo of the dwarf lake iris taken at Maxton Plains.

Plan Your Visit

  • Please note, there is no on-site parking lot available at this location. Visitors may park along the roadside using caution.

    This preserve is open year round. Spring and fall are the two best seasons to visit this preserve, as you'll likely be able to spot migratory birds and wildflowers.

  • Be sure to wear a hat and sunscreen as well as sturdy walking shoes or boots, and bug repellent.

  • The trailhead is located in Benton Township, MI 49721 approximately .2 miles past Thirsty’s Bar and Grill on the left (north side) of US-23, marked with green metal posts.

    Expect rugged, narrow and uneven terrain on natural pathways.

    • No motorized and non-motorized vehicles, including but not limited to automobiles, off-road vehicles (ORVs), all-terrain vehicles (ATVs), motorcycles, snowmobiles, amphibious vehicles and bicycles.
    • No pets
    • No geocaching
    • No removal of trees, plants or animals (alive or dead)
    • No removal of rocks, water or other non-organic materials
    • No camping, bonfires, fireworks or other fires
    • No swimming
  • The Nature Conservancy allows hunting for white-tail deer on this preserve to reduce threats too many deer pose to our conservation targets and to ensure that the preserve does not become a “refuge” for deer during the hunting season.

    In order to be eligible to hunt at this preserve, hunters are required to receive a permit from TNC, follow TNC hunting program rules, and comply with all local, state, and federal laws and ordinances governing hunting activities, including obtaining all required government licenses or permits. For more information, please visit Deer Hunting in Michigan.

  • Have questions about the preserve? Contact Shaun Howard, TNC protected lands project manager in Michigan.

A stream curves through a grassy area at Grass Bay.
Grass Bay Preserve Visit Grass Bay Preserve in spring and fall to spot a variety of wildflowers and migratory birds. © Jason Whalen/Big Foot Media


The Nature Conservancy first became aware of Grass Bay’s amazingly lush and diverse flora in 1978. When the original 80-acre parcel went on the market in 1979, TNC secured an option to purchase it. Because the Federated Garden Clubs of Michigan treasured this site and also wanted to see it protected, they launched a very successful multi-year campaign to raise money to assist TNC in purchasing the original parcel, plus approximately 100 more acres soon after.

Keep Exploring

From shifting sand dunes to granite bald mountains, explore our preserves and reserves spread across the state of Michigan.

Various sized flag markers note different locations on a map.

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.

See the Complete Map

Make a Lasting Impact

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