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Wisconsin State Natural Areas Program Nelson-Trevino Bottoms (No. 81)

Nelson-Trevino Bottoms

Photo by Aaron Carlson



Within the Upper Mississippi River National Wildlife Refuge, Buffalo County. T22N-R13W, Section 6. T22N-R14W, Section 1-4, 10-14. T23N-R14W, Section 31-36. 3,608 acres.



Located below the confluence of the Chippewa and Mississippi Rivers, Nelson-Trevino Bottoms features an extensive, undisturbed wilderness portion of the largest delta floodplain forest in the upper Midwest. Roadless except for a short trail at the southwest corner, the bottoms are a maze of forested floodplain and ever-changing oxbow meanders, marshes, sloughs, and ephemeral ponds. Silver maple, river birch, American elm, and cottonwood dominate wooded areas. Additional canopy species include swamp white oak, bur oak, willow, and green and white ashes. Red osier dogwood occurs in small, scattered fringes and thickets. Herbaceous understory species include wood nettle, partridgeberry, Ontario aster, swamp loosestrife, cut-leaved coneflower, and northern water-horehound. Vines are abundant with poison ivy, common moonseed, Virginia creeper, and bristly greenbriar. Groundcover of open marsh and abandoned stream channels include river bulrush, prairie cord grass, blue-joint grass and sedges. The remoteness combined with a highly productive delta system has allowed extensive and large wildlife populations to flourish. The site is home to many bird species, including pileated woodpecker, blue-gray gnatcatcher, yellow-throated vireo, wood duck, kingfisher, and broad-winged hawk. Mink, and otter are also found here. Nelson-Trevino Bottoms is owned by the U.S. Fish and Wildlife Service and was designated a State Natural Area in 1970.


Driving directions

Access from several locations along Highway 25 between Nelson and Wabasha, MN.


Nelson-Trevino Bottoms is owned by:

  • US Fish & Wildlife Service


The DNR's state natural areas program is comprised of lands owned by the state, private conservation organizations, municipalities, other governmental agencies, educational institutions and private individuals. While the majority of SNAs are open to the public, access may vary according to individual ownership policies. Public use restrictions may apply due to public safety, or to protect endangered or threatened species or unique natural features. Lands may be temporarily closed due to specific management activities. Users are encouraged to contact the landowner for more specific details.

The data shown on these maps have been obtained from various sources, and are of varying age, reliability, and resolution. The data may contain errors or omissions and should not be interpreted as a legal representation of legal ownership boundaries.

To create your own custom map where you can zoom to a specific location, please use the DNR's mapping application.


Very few State Natural Areas have public facilities, but nearly all are open for a variety of recreational activities as indicated below. Generally, there are no picnic areas, restrooms, or other developments. Parking lots or designated parking areas are noted on individual SNA pages and maps. Trails, if present, are typically undesignated footpaths. If a developed trail is present, it will normally be noted on the SNA map and/or under the "Access" tab. A compass and topographic map or a GPS unit are useful tools for exploring larger, isolated SNAs.

The good majority of SNAs are isolated and have few or no facilities. Some SNAs have vehicle access lanes or parking lots, but their accessibility may vary depending on weather conditions. Parking lots and lanes are not plowed during winter. Hiking trails may be nonexistent or consist of undeveloped footpaths. A GPS unit or compass and detailed topographic map are useful tools for exploring larger SNAs.

Non-DNR lands

Entrance fees: For non-DNR-owned SNAs, we are unaware of any vehicle or admission fees. However, please contact the landowner for more information.

Hunting and trapping

This is a non-DNR owned SNA: Opportunities for hunting and trapping depend on the land owner. Please contact them directly to find out about their rules for hunting and trapping. You can find a link to other owner websites under the "Resources" heading above. More details regarding allowable uses of this non-DNR owned SNA may be posted, if available, under the "Access" tab above.

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Other activities

Other allowable activities such as - but not limited to camping, geocaching and bicycling are determined by the landowner. Please contact them directly or visit their websites for details.

Last revised: Monday, March 27, 2023