Common Trees in Wisconsin: Identification Guide

Sugar Maple (Acer saccharum)

As Wisconsin's state tree, sugar maple is the economic and ecological backbone of the state's northern and central forests. Wisconsin is a leading maple syrup producer in the United States, and the Northwoods counties of Burnett, Price, and Langlade are dotted with sugarbushes — maple groves tapped each March when sap begins to run. Sugar maple-basswood forests in the Driftless Area of southwestern Wisconsin, protected in sites like Wyalusing State Park, represent some of the finest stands of this community type in the region. The species drives Wisconsin's most spectacular fall color displays, with the Door County peninsula drawing tens of thousands of visitors each October.

Where to find it: Mesic upland forests, north-facing slopes, ravines, mixed hardwood-conifer stands.

How to identify it:

• Five-lobed leaf with smooth sinuses between lobes, a few teeth at lobe tips
• Gray-brown bark developing irregular, shaggy furrows and plates with age
• Paired samaras with wings held nearly parallel, dispersed in early summer
• Vivid orange, yellow, and red fall color, among the best of any Wisconsin tree

Paper Birch (Betula papyrifera)

Paper birch is the iconic tree of Wisconsin's North Woods, its brilliant white bark glowing against dark conifer backgrounds in the Chequamegon-Nicolet National Forest. It is a pioneer species that colonizes burned, logged, or windthrown areas, and many of Wisconsin's birch forests developed after the great logging era of the 1880s–1910s. The white bark peels in horizontal papery strips, and Indigenous peoples of the Great Lakes region used birch bark extensively for canoes, containers, and shelters. Paper birch is sensitive to bronze birch borer and does not persist in dense shade, making it a transitional species in northern Wisconsin's forest succession.

Where to find it: Upland forests, burned or disturbed areas, bog edges, lakeshores in northern Wisconsin.

How to identify it:

• Brilliant white, papery bark peeling in horizontal strips on mature trees
• Oval to triangular leaves with doubly serrated margins
• Small, cylindrical seed catkins that disintegrate to release tiny winged seeds
• Dark, rough, non-peeling bark on small branches and young twigs

White Pine (Pinus strobus)

White pine was the foundation of Wisconsin's timber economy in the 19th century, and the great log drives on the Wisconsin, Chippewa, and St. Croix rivers sent billions of board feet of white pine lumber downstream to build Midwest cities. Today, old-growth white pine remnants — some over 400 years old — are protected in places like the Pattison State Park, Cathedral Pines in the Chequamegon-Nicolet National Forest, and the Black River State Forest. Wisconsin's white pines regularly exceed 100 feet in height, and second-growth stands now cover much of the north. The five-needle bundles and long, flexible cones are the most reliable field marks.

Where to find it: Sandy soils, lakeshores, rocky ridges, upland forests in northern and central Wisconsin.

How to identify it:

• Needles in bundles of 5, 3–5 inches long, soft and flexible
• Long, slender, slightly curved cones, 4–8 inches long
• Young bark smooth and gray-green; mature bark dark gray with broad, flat ridges
• Distinctive irregular, flat-topped crown on mature trees

Quaking Aspen (Populus tremuloides)

Quaking aspen is the most widely distributed tree in North America and is abundant across northern and central Wisconsin, often forming vast clonal stands called ramets that all share a single root system. The leaves, attached by a flat petiole, tremble in the slightest breeze — hence the name — and produce a distinctive rustling sound. In fall, aspen groves turn a clean, bright gold, and the Hayward-Cable corridor in northwestern Wisconsin is known for outstanding aspen color displays. Ruffed grouse depend heavily on aspen for food and cover, and Wisconsin manages aspen extensively for grouse habitat in the Northwoods.

Where to find it: Disturbed uplands, logged areas, burned sites, lakeshores in northern and central Wisconsin.

How to identify it:

• Small, nearly round leaves with fine teeth and a flattened petiole causing constant motion
• Smooth, pale greenish-white to cream bark on young and mid-aged trees
• Bark becomes dark, rougher, and furrowed only at the very base of old trees
• Clonal growth habit — many stems connected underground as one organism

Balsam Fir (Abies balsamea)

Balsam fir is the quintessential Christmas tree species of Wisconsin's Northwoods and thrives in the cool, moist conditions of the boreal-influenced forests of northern Wisconsin near Lake Superior. It is abundant in the Apostle Islands region, the Bayfield Peninsula, and the Chequamegon-Nicolet National Forest, where it grows alongside white spruce and paper birch in boreal-transition forest communities. The tree releases a sweet, resinous fragrance — the classic 'north woods' scent — from blisters on its smooth bark that contain aromatic resin. Balsam fir is intolerant of drought and heat and is projected to decline in Wisconsin as climate warms.

Where to find it: Cool, moist upland and lowland forests in northern Wisconsin, bog edges, lakeshores.

How to identify it:

• Flat, blunt needles arranged in two rows, dark green above and whitish below
• Smooth gray bark with prominent resin blisters on young trees
• Erect, cylindrical purple-green cones that disintegrate on the tree at maturity
• Strongly aromatic fragrance from needles and bark resin blisters

Bur Oak (Quercus macrocarpa)

Bur oak is the dominant oak of Wisconsin's savanna landscapes and prairie edges, particularly in the Driftless Area of the southwest and the oak savannas of the Central Sands region. It is fire-resistant and was historically maintained in open savanna communities by Indigenous-set fires; without fire management, its savanna habitat quickly succeeds to closed-canopy forest. Wisconsin's best remaining bur oak savannas are protected at the University of Wisconsin-Madison Arboretum, where restoration has been ongoing since the 1930s, and at Baxter's Hollow in the Baraboo Hills. The massive fringed acorn cap is one of the most distinctive features of any Wisconsin oak.

Where to find it: Prairie edges, oak savannas, upland ridges, river terraces, sandy outwash plains.

How to identify it:

• Very large acorn with a mossy, fringed cap covering more than half the nut
• Deeply lobed leaves with a large terminal section and constricted waist
• Thick, deeply furrowed, corky bark on trunk and main branches
• Corky wing-like ridges often visible on younger branches

Basswood (Tilia americana)

Basswood is a co-dominant species in Wisconsin's mesic hardwood forests, often growing alongside sugar maple in the rich hardwood stands of the Driftless Area and the Door Peninsula. It is one of the most important honey-source trees in Wisconsin, with its fragrant cream-colored flowers in early July drawing enormous numbers of bees — bassswood honey is prized across the Great Lakes region. Wisconsin's Indigenous communities historically used basswood inner bark fiber for rope, mats, and baskets. The large, heart-shaped leaves and distinctive leaf-like bract attached to the fruit cluster make it easy to identify.

Where to find it: Moist upland forests, ravines, north-facing slopes, mixed hardwood stands.

How to identify it:

• Large, heart-shaped, asymmetrical leaves with toothed margins
• Distinctive elongated leafy bract attached to the fruit stalk
• Clusters of small, fragrant cream-yellow flowers in July
• Round, hard, pea-sized nutlets hanging from the bract in clusters

Yellow Birch (Betula alleghaniensis)

Yellow birch is the largest native birch in Wisconsin and is associated with the state's most mature, undisturbed northern hardwood forests. Unlike paper birch, yellow birch is shade-tolerant and persists in old-growth forest conditions alongside sugar maple, beech, and hemlock in the Northwoods. Its bronze to golden-yellow, peeling bark releases a distinct wintergreen scent when a twig is scratched — one of the most reliable field marks of any Wisconsin tree. The Porcupine Mountains Wilderness State Park just across the border in Michigan hosts forest communities similar to what once covered much of Wisconsin's upper north.

Where to find it: Cool, moist upland forests, ravines alongside hemlock and sugar maple in northern Wisconsin.

How to identify it:

• Shiny bronze-gold to silver-gray bark peeling in horizontal, papery curls
• Twigs and inner bark have a distinct wintergreen fragrance when scratched
• Oval, doubly serrated leaves similar to paper birch but more elongated
• Oval, erect seed catkins that disintegrate at maturity

Common Buckthorn

Common buckthorn (Rhamnus cathartica) is one of the most damaging invasive shrub-trees in Wisconsin, forming dense, shade-casting thickets in forests, savannas, and roadsides across the southern two-thirds of the state. It leafs out early, holds leaves late, and produces abundant berries spread by birds, allowing it to outcompete native understory plants. The Wisconsin DNR has identified it as a priority management target in southern Wisconsin's oak woodlands and savannas.

Norway Maple

Norway maple (Acer platanoides), widely planted as a street tree across Wisconsin's cities, has naturalized into urban forest edges, parks, and riparian corridors. It is nearly identical in appearance to native sugar maple but can be distinguished by its milky sap at the leaf petiole base and more widely spread samara wings. It shades out native understory plants and competes with sugar maple regeneration in forest edges near urban areas.

Glossy Buckthorn

Glossy buckthorn (Frangula alnus) is particularly aggressive in Wisconsin's wetland edges, sedge meadows, and bog margins — habitats where common buckthorn is less dominant. It is widespread in the northern two-thirds of the state and poses a significant threat to the state's globally rare open peatland communities in the Northwoods. Early detection and removal before fruiting is the most effective control strategy.

What trees are most common in northern Wisconsin?

Northern Wisconsin's Chequamegon-Nicolet National Forest is dominated by quaking aspen, paper birch, balsam fir, white spruce, white pine, and sugar maple. These species reflect the boreal forest influence of the Great Lakes region and the cool climate of Wisconsin's upper north, which is climatically more similar to Canada than to the state's southern counties.

Why is Door County famous for fall foliage?

Door County's peninsula position between Green Bay and Lake Michigan creates a unique microclimate that delays killing frosts, extending the fall color season and producing exceptionally vivid sugar maple displays. The county's mix of sugar maple, yellow birch, and basswood forests, combined with scenic shoreline views, makes it one of the premier fall destinations in the Midwest.

Are there old-growth trees in Wisconsin?

Yes, though rare. Old-growth remnants survive in the Chequamegon-Nicolet National Forest, Pattison State Park, and several state natural areas. The most accessible old-growth white pines and hemlocks in Wisconsin are found in the Cathedral Pines area and the Lost Lake Research Natural Area, where trees exceed 300–400 years in age.