Trees in Your Pocket: A Guide to Trees of the Upper Midwest (Bur Oak Guide) [1 ed.] 1609381238, 9781609381233

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a b ur oak gu ide

in your pocket A Guide to Trees of the Upper Midwest

thomas rosburg

White oak

Quercus alba

Simple, alternate leaves; blades �½ to � inches long; � to �� lobes without bristles; notches between lobes deep, reaching �� to ��% of distance to middle vein. Fruit an acorn, cup covering lower ¼ to ½. Dominant or codominant in upland forests on ridges and upper slopes. Intermediate shade tolerance, moderate fire tolerance. Life span ��� years. MO, IL, e¾ IA, se & ec MN, s2/3 WI Largest diameter: � feet, � inch, Putnam IL Tallest tree: ��� feet, Waukesha WI

Swamp white oak Quercus bicolor

Simple, alternate leaves; blades � to �½ inches long; � to �� small lobes or blunt teeth without bristles; notches between lobes shallow, reaching �� to ��% of distance to middle vein. Fruit an acorn in pairs on the end of a stalk � to � inches long, cup covering lower ½ to ¾. Mixed forests or savannas on floodplains, margins of sloughs. Intermediate shade and flood tolerance. Life span ��� to ��� years. n½ MO, IL, se½ IA, se½ MN, s½ WI Largest diameter: � feet, � inches, Manitowoc WI Tallest tree: ��� feet, Manitowoc WI

Bur oak

Quercus macrocarpa

Simple, alternate leaves; blades �½ to � inches long; lower half deeply lobed, upper half shallowly lobed or unlobed without bristles; margins wavy or coarsely toothed. Fruit an acorn with a fringe of bristles on cup rim, cup covering lower ½ to ¾. Dominant on savannas and in woodlands. Intermediate shade tolerance, drought and fire tolerant. Life span ��� years. MO, IL, IA, MN, WI Largest diameter: � feet, � inches, Boone MO Tallest tree: �� feet, Boone MO

Shingle oak

Quercus imbricaria

Simple, alternate, unlobed leaves; blades � to � inches long with a single bristle on the tip and smooth margins; upper surface shiny dark green. Fruit an acorn, cup covering lower 1⁄3 to 1⁄2; scales of cup tightly pressed. Mixed early to late successional forests or mixed oak woodlands in moist to dry upland soils. Tolerant of sterile or poor soils. MO, s3⁄4 IL, s1⁄4 IA Largest diameter: � feet, � inches, St. Louis MO Tallest tree: ��� feet, St. Louis MO

Chinkapin oak

Quercus muehlenbergii

Simple, alternate leaves; blades �1⁄2 to � inches long, leathery; 8 to 15 pairs of parallel veins ending in large, gland-tipped teeth or small lobes without bristles. Fruit an acorn, cup covering lower 1⁄4 to 1⁄2; scales of cup tight with a conspicuous rounded keel. Mixed forests or oak woodlands on dry and rocky ridges, south slopes, bluffs. Shade intolerant. Life span 400 years. MO, IL, se1⁄2 IA, se1⁄8 MN, s1⁄4 WI Largest diameter: 5 feet, 5 inches, St. Charles MO Tallest tree: 82 feet, Fremont IA

Downy hawthorn or red haw Crataegus mollis

Simple, alternate leaves; blades 3 to 5 inches long, egg-shaped, coarsely toothed, and either unlobed or with 4 to 10 short lobes. Fruit fleshy, red, 1⁄2 to 3⁄4 inch in diameter. Thorns 1 to 2 inches long. Small understory tree in damp forests or early successional woodlands, brushy ravines, along edges, pastures, fire-protected sites. Shade intolerant. MO, IL, IA, MN, sw3⁄4 WI Largest diameter: 2 feet, 91⁄2 inches, Will IL Tallest tree: 48 feet, Will IL

Hackberry

Celtis occidentalis

Simple, alternate leaves, egg- to lance-shaped; blades 2½ to 5 inches long; margins toothed; leaf base uneven; 3 prominent veins from the base. Fruit fleshy, purple, ¼ to ½ inch in diameter. Bark gray with corky ridges or protrusions. Mixed forests on floodplains, lowlands, upland early successional sites. Intermediate shade tolerance, flood and drought tolerant. Life span 200 years. MO, IL, IA, s½ MN, s½ WI Largest diameter: 5 feet, 9 inches, Lincoln MO Tallest tree: 96 feet, Sangamon IL

American elm

Ulmus americana

Simple, alternate leaves; blades 3 to 6 inches long; margins coarsely toothed; leaf base uneven. Fruit single-seeded and dry, encircled by a thin, short papery wing with short hairs on margins. Bark ridges layered with red and white cork 1/16 inch thick. Floodplains, lowlands, riparian forests, hardwood swamps. Intermediate shade and flood tolerance, fairly fire intolerant. Life span 400+ years. MO, IL, IA, MN, WI Largest diameter: 6 feet, 5 inches, Milwaukee WI Tallest tree: 114 feet, Madison IL

Red elm or slippery elm Ulmus rubra

Simple, alternate leaves; blades 3½ to 7 inches long; margins coarsely toothed; leaf base uneven. Fruit single-seeded and dry, encircled by a thin, short papery wing that is hairless. Bark ridges layered solely with red cork or very thin and barely distinct white layers. Mixed forests on lowlands, terraces, moist uplands, early successional sites. Shade tolerant, intermediate flood tolerance. MO, IL, IA, s½ MN, s2⁄3 WI Largest diameter: 4 feet, 6 inches, Henry IL Tallest tree: 88 feet, Milwaukee WI

Northern red oak Quercus rubra

Simple, alternate leaves; blades 4 to 7 inches long; 7 to 11 slightly tapered lobes with bristles; notches between lobes 45 to 60% of distance to middle vein. Fruit an acorn, cup covering lower ¼ to ½; cup scales tight.Codominant in upland forests, ravines, on north and east slopes, stream terraces. Intermediate shade tolerance, drought and fire intolerant. Life span 200 to 300 years. MO, IL, se⅞ IA, e¾ MN, WI Largest diameter: 6 feet, Dane WI Tallest tree: 85 feet, Dane WI

Black oak

Quercus velutina

Simple, alternate leaves; blades 3½ to 7 inches long; 5 to 9 lobes with bristles; notches between lobes 65 to 85% of distance to middle vein. Fruit an acorn, cup comprising lower ½ to ¾, domeshaped; scale tips loose. Buds with dense grayish white hairs. Woodlands and savannas, dry slopes, ridges, sandy or gravelly soils. Intermediate shade tolerance, fairly drought tolerant. MO, IL, se2⁄3 IA, se⅛ MN, s½ WI Largest diameter: 5 feet, 7 inches, Green WI Tallest tree: 85 feet, Johnson IA

Ohio buckeye Aesculus glabra

Opposite, compound leaves with 5 to 7 leaflets all arising from a common point; blades 3 to 6 inches long, finely toothed. Fruit a leathery, prickly capsule containing 1 to 3 large brown seeds. Flowers showy, greenyellow, in clusters 5 to 6 inches long, blooming in spring. Subcanopy tree 30 to 40 feet tall in moist forests of streambanks, lowlands, valleys. Shade tolerant. MO, s¾ IL, s½ IA Largest diameter: 4 feet, 8 inches, DuPage IL Tallest tree: 73 feet, DuPage IL

Bitternut hickory Carya cordiformis

Alternate, compound leaves 6 to 10 inches long with 7 to 9 leaflets, terminal leaflet largest; blades 3 to 6 inches long. Buds elongate and yellow. Fruit a fleshy, 4-ridged husk ¾ to 1¼ inches in diameter that splits halfway open to expose a light brown nut. Mixed mid to late successional forests, wet to dry sites, favors moist soils. Shade and fire intolerant. Life span 200 years. MO, IL, se¾ IA, se & ec MN, s2⁄3 WI Largest diameter: 3 feet, 8 inches, Bureau IL Tallest tree: 117 feet, Calumet WI

Shagbark hickory Carya ovata

Alternate, compound leaves 8 to 14 inches long with 5 (rarely 7) leaflets, terminal leaflet largest; blades 4 to 8 inches long. Fruit a fleshy, 4-lined husk 1¼ to 2 inches long that splits fully open to release a 4-ribbed tan nut. Mature bark in vertical strips curling outward (shaggy). Dry uplands and slopes with oaks, early to late successional sites, less common in lowland forests. Life span 250 to 300 years. MO, IL, se2⁄3 IA, se¼ MN, s½ WI Largest diameter: 3 feet, 1 inch, Dubuque IA Tallest tree: 93 feet, Houston MN

Black walnut Juglans nigra

Large, alternate, compound leaves 1 to 2 feet long with 12 to 20 leaflets, largest in the center; blades 3 to 5½ inches long; terminal leaflet usually absent; foliage aromatic. Fruit a fleshy husk 1½ to 2 inches in diameter that encloses a grooved nut. Pith of twigs chambered. Mixed forests, alluvial soils of valleys, terraces, lower slopes. Shade intolerant, fairly flood tolerant. Life span 250 years. MO, IL, IA, s¼ MN, s¼ WI Largest diameter: 5 feet, 6 inches, Kendall IL Tallest tree: 107 feet, Des Moines IA

White ash

Fraxinus americana

Opposite, compound leaves 8 to 12 inches long with 5 to 9 leaflets; blades 2½ to 5½ inches long; margins slightly toothed or entire, turning reddish purple in fall; leaflet stalks ¼ to ½ inch long. Fruit single-seeded and dry with an elongate, narrow papery wing. Mixed forests on moist uplands or slopes, early to late successional sites. Shade intolerant but persists in shade as seedlings, low flood tolerance. Life span 300 years. MO, IL, se¾ IA, se & ec MN, WI Largest diameter: 6 feet, 11 inches, Sangamon IL Tallest tree: 91 feet, Des Moines IA

Black ash

Fraxinus nigra

Opposite, compound leaves 12 to 16 inches long with 9 to 11 leaflets; blades 3 to 6 inches long; margins toothed; leaflet stalks absent. Fruit single-seeded and dry with an elongate, narrow papery wing. Bark scaly, not deeply furrowed. Mixed forests, moist to wet sites, on floodplains, lower slopes, in valleys. Shade intolerant, tolerant of seasonal flooding in swamps and bogs. Life span 250 years. n¼ IL, ne½ IA, ne½ MN, WI Largest diameter: 3 feet, 4 inches, Washington MN Tallest tree: 98 feet, Jones IA

Green ash

Fraxinus pennsylvanica

Opposite, compound leaves 10 to 12 inches long with 5 to 9 leaflets; blades 3 to 5 inches long; margins toothed, turning yellow– rusty brown in fall; leaflet stalks ⅛ to 1⁄6 inch long. Fruit singleseeded and dry with an elongate, narrow papery wing. Early to late successional mixed forests, favors wet soils, floodplains, riparian sites, colonizes upland sites. Tolerates drought. Life span 175 years. MO, IL, IA, MN, WI Largest diameter: 6 feet, 5½ inches, Dewitt IL Tallest tree: 102 feet, Waukesha WI

Boxelder

Acer negundo

Opposite, compound leaves with 3 leaflets (sometimes 5, rarely 7); blades 2 to 4 inches long; margins with a few notches or large teeth. Young twigs green in summer, turning reddish purple in winter. Fruit single-seeded and dry with an elongate papery wing, maturing in pairs. Riparian habitats, floodplains, and lowlands, also early successional uplands. Shade tolerant, fairly flood and drought tolerant, fire intolerant. Life span rarely 100 years. MO, IL, IA, sw¾ MN, WI Largest diameter: 4 feet, 11 inches, Ramsey MN Tallest tree: 70 feet, Waukesha WI

Black maple Acer nigrum

(sometimes considered same species as sugar maple)

Opposite, simple leaves; blades 3½ to 6 inches long with 3 lobes, angle between main lobes 80° or greater, lobe tips droop; youngest leaves with small paired appendages where they attach to the twig. Fruit single-seeded and dry with an elongate papery wing, maturing in pairs. Dominant in late successional forests in moist soils of north and east slopes, in river valleys. Very shade tolerant, fairly flood tolerant. Life span 300 to 400 years. ne½ MO, IL, e¾ IA, se¼ MN, sw½ WI Largest diameter: 5 feet, 4 inches, Marshall IA Tallest tree: 85 feet, Waushara WI

Silver maple

Acer saccharinum

Opposite, simple leaves; blades 3 to 4½ inches long with 5 lobes; notches between main lobes deep and V-shaped; lower surface of leaf blade silvery white. Fruit singleseeded and dry with an elongate papery wing, maturing in pairs, but with one fruit often aborted. Dominant in floodplains, riparian sites. Flowers in early spring so seed can disperse onto floodexposed sites. Shade and flood tolerant. Rapid growth. Life span 130+ years. MO, IL, IA, MN (except upper wc), WI Largest diameter: 8 feet, 3 inches, Houston MN Tallest tree: 121 feet, Saline MO

Yellow birch

Betula alleghaniensis

Simple, alternate leaves; blades 2 to 4½ inches long; spur shoots bear a pair of leaves; leaf base round to slightly heart-shaped. Fruit single-seeded and dry with a small wing, borne in a short, eggshaped, erect conelike structure. Twigs have a wintergreen taste. Canopy species of mixed forests ranging from early to late successional and from wet to rocky soils. Intermediate shade tolerance, fire intolerant. n⅛ IL, ne¼ IA, e½ MN, WI Largest diameter: 4 feet, 9 inches, Iron WI Tallest tree: 73 feet, Iron WI

River birch Betula nigra

Simple, alternate leaves; blades 2 to 4 inches long with coarsely toothed margins; spur shoots bear a pair or trio of leaves; leaf base wedge-shaped. Fruit singleseeded and dry with a small wing, borne in a short, egg-shaped conelike structure. Young bark peels in thin orange sheets. Floodplains, riverbanks. Seed dispersal occurs during spring floods. Shade intolerant, intermediate flood tolerance. MO, sw2⁄3 IL, se1⁄3 IA, se¼ MN, s2⁄3 WI Largest diameter: 3 feet, 10 inches, Johnson IA Tallest tree: 78 feet, Johnson IA and Ramsey MN

Paper birch Betula papyrifera

Simple, alternate leaves; blades 2 to 4 inches long; spur shoots bear a pair or trio of leaves; leaf base round to nearly straight. Fruit single-seeded and dry with a small wing, borne in a cylindrical conelike structure. Bark peels into thin white strips. Mixed forests, often in disturbed patches, in soils ranging from thin and rocky to shallow, soggy peat; prefers cool, moderately deep, moist soils. Shade intolerant. Capable of rapid growth. n⅛ IL, ne¼ IA, ne2⁄3 MN, WI Largest diameter: 3 feet, 6 inches, Marinette WI Tallest tree: 95 feet, Marinette WI

Ironwood or hop-hornbeam Ostrya virginiana

Simple, alternate leaves; blades 3 to 5 inches long; leaf base even, rounded, or slightly heart-shaped, surface smooth. Fruit a small nutlet enclosed in papery sacs borne in a drooping cylindrical cluster. Bark grayish, in tight vertical rows. Subcanopy tree of late successional upland forests under oak, maple, or basswood. Shade tolerant. Slow growth produces extremely hard wood. MO, IL, IA, MN, WI Largest diameter: 3 feet, 1 inch, Faribault MN Tallest tree: 65 feet, Green WI

Black cherry Prunus serotina

Simple, alternate leaves; blades 2½ to 5 inches long; elliptical, lower surface with rusty hairs along lower middle vein. Fruit fleshy, black, ¼ to 1⁄3 inch in diameter. Bark splits into grayish or black scales with outturned edges. Mixed upland forests, early to mid successional sites, edges, pastures. Shade intolerant but persists in shade as seedlings. MO, IL, se⅞ IA, se & ec MN, WI Largest diameter: 5 feet, 1½ inches, Dane WI Tallest tree: 105 feet, Fillmore MN

Redbud

Cercis canadensis

Simple, alternate, heart-shaped leaves; blades 2½ to 5 inches long with smooth margins; several large veins arise from a common point at the base. Fruit a flat legume 2 to 3½ inches long. Flowers pink, conspicuous, present before leaf-out. Small understory tree, usually to 25 feet tall, in late successional upland forests, also along field edges and streambanks. Pollinated by bees. MO, s2⁄3 IL, s1⁄3 IA Largest diameter: 3 feet, 1 inch, St. Clair IL Tallest tree: 33 feet, Des Moines IA

Honey locust

Gleditsia triacanthos

Alternate, compound leaves 4 to 12 inches long with 14 to 90+ elliptic leaflets ½ to 1½ inches long. Large thorns usually present (a thornless cultivar is planted). Fruit a distinctive flat, twisted, or curved legume 6 to 16 inches long. Formerly floodplains or lowlands, now pervasive in lowland and upland early successional habitats, along edges, pastures. MO, IL, IA, se⅛ MN, s¼ WI Largest diameter: 5 feet, 9 inches, Callaway MO Tallest tree: 145 feet, McLean IL

Kentucky coffee tree Gymnocladus dioicus

Large, alternate, twice-compound leaves 1 to 3 feet long with 50 to 120+ egg-shaped leaflets 1½ to 3 inches long. Fruit a distinctive thick, rigid legume 3½ to 6 inches long, 1 to 2 inches wide. Sporadic, associated with moist soils of lowland forests on floodplains, on terraces, along streambanks, lower slopes. MO, IL, IA, s¼ MN, s1⁄3 WI (disconnected in north) Largest diameter: 4 feet, 8 inches, Warren MO Tallest tree: 122 feet, Jefferson WI

Black locust

Robinia pseudoacacia

Alternate, compound leaves 6 to 14 inches long with 7 to 19 elliptic leaflets 1½ to 2 inches long. Spines in pairs on branches and twigs. Fruit a flat legume 2 to 4 inches long, ½ inch wide. Flowers large, white, showy, present in late spring. Native in MO and IL, invasive elsewhere. Early successional habitats, woodlands, edges, fields. MO, IL, IA, se½ MN, WI Largest diameter: 5 feet, 3 inches, Montgomery IL Tallest tree: 76 feet, Montgomery IL

White mulberry Morus alba

Simple, alternate leaves; blades 2 to 5 inches long; margins coarsely toothed, variable shape, most with irregular lobes; hairs on lower surface confined to main veins and axils. Fruit fleshy, ½ to 1 inch long, a cluster of many fruitlets, purplish black when ripe. Bark gray with orange-tinged furrows. Nonnative; somewhat invasive on weedy, open disturbed sites and along edges. MO, IL, IA, s1⁄3 MN, s½ WI Largest diameter: 5 feet, 10 inches, Linn IA Tallest tree: 52 feet, Linn IA and Lafayette MO

Red mulberry Morus rubra

Simple, alternate leaves; blades 5 to 9 inches long; margins coarsely toothed, mostly unlobed but can have 2 to 3 lobes; hairs on entire lower surface. Fruit fleshy, ½ to 1 inch long, a cluster of many fruitlets, purplish black when ripe. Uncommon understory tree in moist soils, ravines, on floodplains, lower slopes. Shade tolerant, moderately flood tolerant. MO, IL, se2⁄3 IA, se¼ MN, s½ WI Largest diameter: 3 feet, 6 inches, Walworth WI Tallest tree: 55 feet, Walworth WI

American basswood Tilia americana

Simple, alternate leaves; blades 3 to 6 inches long, nearly round; margins sharply toothed; leaf base heart-shaped and uneven. Fruit dry, hard, spherical, ¼ to 1⁄3 inch in diameter. Bark dark gray, furrowed, with long parallel ridges. Commonly produces a cluster of multiple trunks. Codominant in late successional forests on moist north and east slopes, terraces, drainage ways. Shade tolerant, fire intolerant. Fairly rapid growth. MO, IL, IA, MN, WI Largest diameter: 7 feet, 4 inches, Outagamie WI Tallest tree: 87 feet, Hamilton IA

Sycamore

Platanus occidentalis

Simple, alternate leaves; blades 4 to 8 inches long with 3 to 5 pointed lobes; margins sparsely and coarsely toothed; 3 prominent veins from the base. Fruit a dense, round cluster of tiny dry fruits. Young bark smooth, thin, peeling, mottled white, gray, or reddish. Floodplains, riparian habitats, early to late successional sites. Intermediate shade tolerance. Rapid growth. Lifespan 500 to 600 years. MO, IL, s2⁄3 IA, sw corner WI Largest diameter: 9 feet, 10½ inches, Christian IL Tallest tree: 119 feet, Christian IL

White poplar Populus alba

Simple, alternate leaves; blades 2 to 5 inches long, unlobed with a few broad teeth or 3 to 5 short lobes; lower surface densely white wooly. Fruit a flask-shaped capsule ⅛ to ¼ inch long, tiny seeds with cottony hairs. Nonnative in human-modified habitats, troublesome and invasive due to vigorous rootsuckering. Short-lived. MO, IL, IA, MN, WI Largest diameter: 6 feet, 8 inches, Fond du Lac WI Tallest tree: 96 feet, Fond du Lac WI

Eastern cottonwood Populus deltoides

Simple, alternate leaves, triangular; blades 2½ to 5 inches long; margins with many rounded teeth; leaf base straight. Fruit an egg-shaped capsule ¼ to 1⁄3 inch long, tiny seeds with cottony hairs. Older bark thick, grayish, deeply furrowed. Floodplains, riparian habitats, wet seeps. Seed dispersal during spring floods. Very shade intolerant. Rapid growth. Life span 100 to 200 years. MO, IL, IA, s½ MN, s2⁄3 WI Largest diameter: 10 feet, 5½ inches, Chippewa MN Tallest tree: 154 feet, Buffalo WI

Bigtooth aspen

Populus grandidentata

Simple, alternate leaves, eggshaped; blades 2 to 4½ inches long; margins coarsely toothed; leaf base round. Fruit an eggshaped capsule ⅛ to ¼ inch long, tiny seeds with cottony hairs. Mixed upland moist forests in disturbed patches or early successional sites. Very shade intolerant. Rapid growth. Clonal growth from root suckers is common. ne corner MO, n¼ IL, e½ IA, e2⁄3 MN, WI Largest diameter: 3 feet, 1½ inches, Iron WI Tallest tree: 114 feet, Kanabec MN

Quaking aspen

Populus tremuloides

Simple, alternate leaves, broadly egg-shaped to nearly round; blades 1½ to 3 inches long; margins with many fine teeth. Fruit an egg-shaped capsule ⅛ to ¼ inch long, tiny seeds with cottony hairs. Dry to moist uplands in disturbed patches or early successional sites. Very shade intolerant, fire adapted. Rapid growth. Vigorous clonal growth from root suckers. ne corner MO, n¼ IL, ne½ IA, MN, WI Largest diameter: 3 feet, 3 inches, Crow Wing MN and Ashland WI Tallest tree: 96 feet, Crow Wing MN

Black willow Salix nigra

Simple, alternate leaves; blades 2½ to 6 inches long, 5 to 11 times longer than wide; margins finely toothed; both surfaces a similar shade of green. Fruit a flaskshaped capsule ⅛ to ¼ inch long, tiny seeds with cottony hairs. Floodplains, swamps, open riparian habitats, early successional sites. Very shade intolerant, very flood tolerant. Life span 85 years. MO, IL, IA, se1⁄3 MN, s¾ WI Largest diameter: 9 feet, 10½ inches, Hennepin MN Tallest tree: 81 feet, Winneshiek IA

Common buckthorn Rhamnus cathartica

Simple, opposite or nearly opposite (rarely alternate) leaves; blades 1 to 2½ inches long, elliptic to round; 3 to 4 pairs of curving veins; dark green upper surface. Fruit fleshy, black, ¼ inch in diameter. Thorns often at tips of older twigs. Nonnative small tree or shrub, invasive in all habitats, noxious weed in IA and MN. Shade, flood, and drought tolerant. ne¼ MO, n2⁄3 IL, ne2⁄3 IA, MN, WI Largest diameter: 1 foot, 3 inches, Polk IA Tallest tree: 31 feet, Polk IA

leaflet

simple leaf

compound leaf

alternate leaves

opposite leaves

Drawings by Brent Butler, The Tallgrass Prairie Center Guide to Seed and Seedling Identification in the Upper Midwest

Valued for their lumber, their shade, and the beauty of their flowers and foliage as well as the nuts that nourish wildlife and humans alike, trees play important economic, ecological, and aesthetic roles in our lives. From maples to oaks to birches, Trees in Your Pocket provides identification and natural history information about forty prominent deciduous species found in the Upper Midwest states of Minnesota, Wisconsin, Illinois, Iowa, and Missouri.   Botanist Tom Rosburg provides diagnostic color photographs of leaves, acorns and other fruits, and bark along with descriptions and measurements of leaves and blades. The composition, arrangement, shape, and margin of leaves are most important for tree identification. Fruits can help confirm identification of separate species with similar leaves. The bark of a tree can be very helpful for identifying some species; as a tree ages, older bark (lower on the tree) can be quite different from younger bark (higher and on branches). In addition to these essential markers, Rosburg gives information about the trees’ range, habitat—savannas, moist forests, dry slopes, sandy soils, and so on—life-span, and tolerance of shade, fire, drought, and flood.   Each state in this region maintains a Big Tree program that honors the largest individual tree of each species. Champion trees are determined by adding together measurements of trunk circumference, height, and canopy spread. Rosburg identifies the trees with the largest diameter and the tallest trees among the champion trees in the Upper Midwest by their county and state. Together his superb photographs and key information make this guide the perfect companion for enjoying the diversity of trees in all kinds of environments. Copyright © 2012 by the University of Iowa Press. Printed in the U.S.A. $9.95

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