TREES AND SHRUBS

A KEY TO SOUTH DAKOTA TREES

(Modified from the key developed by Collins and Helwig in The Trees of South Dakota, 
SDSU Extension Circular 566)

1a. Leaves green over winter; fruit a dry cone or berry-like ............................................................2
b. Leaves turn color and usually shed in the fall; fruit variable ........................................................15
2a. Leaves needle-like; fruit a dry cone ............................................................................................3

b. Leaves scale-like or awl-shaped; fruit a dry cone or berry-like ...................................................13

3a. Several needles attached to the branch in bunches of 2 or more .................................................4

b. Needles attached to the branch singly ...........................................................................................9

4a. Needles in bunches of five or more (may be single needles on new shoots) ...................................5
b. Needles in bunches of two's or two's and three's ..........................................................................6
5a. Needles in bunches of five; needles 3" to 5" long, slender, flexible ...........................................Eastern White Pine
b. Needles single on new shoots but in bunches on older stems; needles shorterthan 2", lost in fall ....European Larch
6a. Needles in bunches of two's or three's; needles more than 4 inches long ...................................Ponderosa Pine
b. Needles in bunches of two's; needles 4 inches long or shorter ..................................................7
7a. Needles more than 3 inches long, stiff and sharp-pointed ..........................................................Austrian Pine
b. Needles usually shorter than 3 inches ........................................................................................8
8a. Needles flexible; cones point back toward trunk .......................................................................Scotch Pine

b. Needles stiff; cones point forward, away from trunk .................................................................Jack Pine
9a. Needles 4-sided, pointed and easily rolled between two fingers ..............................................10
b. Needles flattened, not sharp pointed, and will not roll easily between fingers .........................12
10a. Needles yellowish-green; twigs pendulous; cones 3" to 7" long .............................................Norway Spruce
b. Needles whitish-green or bluish-green; cones less than 4" ......................................................11
11a. Needles rigid and sharp-pointed; cones 2 5" to 4" with papery, wedge-shaped scales ...........Blue Spruce
b. Needles not as sharp to the touch; cones shorter than 2" with rounded scales ...........................White Spruce
12a. Needles with short petioles and not sharp to the touch; cones 2" to 4" long with 3-pointed bracts extending beyond the scales ..................................................................................................Douglas-fir

b. Needles without petioles; bracts on cones shorter than scales ..................................................White Fir
13a. Leaves all scale-like; branchlets flat in cross section; fruit a small, dry cone Northern ..........White-cedar

b. Leaves both scale-like and awl-shaped; branches 4-angled in cross section; fruit berry-like ...14

14a. Leaves usually dark green; fruit ripens in one season ..............................................................Eastern Redcedar
b. Leaves silvery to pale green; fruit ripens in two seasons ..........................................................Rocky Mountain Juniper
15a. Needles single on new shoots but in bunches on older stems ..................................................European Larch
b. Leaves not needle-like but with an expanded blade ..................................................................16

16a. Leaves two or more on opposite side of branch at same spot (opposite or whorled) ..............17

b. Leaves only one at a location on a stem (alternate) ...................................................................25

17a. Large smooth-edged leaves attached 3 or more around the stem; fruit a long bean pod ...........Northern Catalpa

b. Two leaves attached opposite one another on a stem ................................................................18
18a. Leaves composed of several small leaflets (compound) .........................................................19

b. Leaves composed of one single blade (simple) .........................................................................21

19a. Leaflets arise from a common point of attachment (palmately compound) ...............................Buckeye

b. Leaflets attached opposite one another along a central stem (pinnately compound) ...................20

20a. Leaflets 3 to 5 arranged as shown; fruit a double samara .........................................................Boxelder

b. Leaflets 7 to 9 and toothed; fruit a single samara .......................................................................Green Ash

21a. Small, shrubby tree; leaves 3-lobed with central lobe longer than side ones; leaf edges doubly serrate .....Amur Maple

b. Large tree, leaves with 3 to 5 lobes that are either smooth or toothed .......................................22
22a. Leaves silvery underneath with edges toothed; fruit ripens in spring .......................................Silver Maple

b. Edges of leaves smooth; fruit ripens in fall ................................................................................23
23a. Sap milky; samara wings widely divergent ..............................................................................Norway Maple
b. Sap not milky; samara wings form horse-shoe shaped fruit ........................................................24
24a. Leaves usually 3-lobed, green and hairy along veins below; petioles hairy .............................Black Maple

b. Leaves usually 5-lobed, whitish-green and hairless below; petioles hairless ............................Sugar Maple
25a. Leaves pinnately compound ......................................................................................................26

b. Leaves are single blades .............................................................................................................33

26a. Stems with spines or thorns .......................................................................................................27
b. Stems without spines or thorns ....................................................................................................28
27a. Stems with paired spines at the base of each leaf; fruit small bean pod ....................................Black Locust
b. Stems with stout, often branched thorns arising above leaf attachment point; fruit a long, often twisted, bean pod ...Honeylocust

28a. Fruit a bean-like pod; leaflets smooth or finely toothed .............................................................29
b. Fruit not bean-like; leaflets sharply toothed .................................................................................30
29a. Leaves bipinnately compound; leaflets smooth edged ................................................................Kentucky Coffeetree
b. Leaves can be either pinnately or bipinnately compound; leaflet finely toothed ...........................Thornless Honeylocust
30a. Fruit a nut; bark ridged ................................................................................................................31
b. Fruit small and apple-like, occurring in clusters; bark smooth ......................................................32
31a. Nut spherical; bark with deep, narrow furrows and ridges ..........................................................Black Walnut
b. Nut oval; bark with shallow furrows and broad ridges ..................................................................Butternut
32a. Leaf stem and lower surface of leaflets can have dense, white hairs, leaflets rounded;
winter buds densely covered with white hairs .............................................................................European Mountain-ash

b. Leaf stem and lower surface of leaflets lack hairs; leaflets pointed tipped;
winter buds are hairless or, almost hairless ..................................................................................American Mountain-ash
33a. Leaves variously lobed or smooth without being toothed ............................................................34
b. Leaves variously toothed ...............................................................................................................43
34a. Leaves long, slender and smooth edged with silvery scales on top and bottom;
fruit small, yellow and olive-like ................................................................................................Russian-olive

b. Leaves lobed, not silvery above and below ..................................................................................35
35a. Leaves palmately 3 to 5 lobed; leaf edges coarsely toothed; bark mottled
on trunk; fruit rough, dry sphere ....................................................................................................Sycamore
b. Leaves not palmately lobed; fruit not as described above .............................................................36
36a. Sap milky; lobed and non-lobed leaves on same tree; multiple, fleshy, blackberry-like fruit ......37
b. Sap watery; fruit single or cone-like ..............................................................................................39
37a. Leaves rough above, hairy below; fruit reddish-black when ripe ................................................Red Mulberry
b. Leaves smooth above nearly hairless below; fruit variable in color .............................................38
38a. Leaves 2" to 5" long; fruits up to 1 " long, white, pink or purplish violet ...................................White Mulberry
b. Leaves up to 3" long; fruit 1/2" long, dark red ..............................................................................Russian Mulberry
39a. Leaf lobes smooth and rounded; fruit an acorn ............................................................................Bur Oak

b. Leaf lobed with edges variously indented; fruit not an acorn ........................................................40
40a. Young twigs, buds and underside of leaves covered by dense cottony felt; leaves shiny
and dark green above, variously lobed to coarsely toothed, and palmately veined .....................41
b. Twigs and leaves not as above; leaves pinnately veined ..............................................................42
41a. Tree with a broad crown; bark smooth and whitish except at base ............................................White Poplar

b. Tree branches pointing upward forming a narrow columnar crown .............................................Bolleana Poplar
42a. Bark white and papery; leaves deeply and sharply cut; fruit small, cone-like ............................Cutleaf Weeping Birch

b. Bark reddish to grayish-brown; leaves not as sharply cut; fruit apple-like ..................................Crab Apple
43a. Bark of main limbs and trunk white or greenish-white to light green .........................................44
b. Bark usually variously shades of gray or reddish-brown ............................................................51
44a. Bark white and papery; fruit cone-like and ripens in fall ...........................................................45

b. Bark greenish-white to green but not papery; fruit on a drooping catkin that ripens in spring ......46
45a. Bark dark-furrowed at base of trunk; leaves ovate to triangular .................................................European White Birch
b. Bark remains papery on older trunks; leaves ovate ......................................................................Paper Birch
46a. Young twigs, buds and underside of leaves covered by dense cottony felt;
leaves shiny and dark green above, usually some of leaves lobed .............................................41
b. Twigs and leaves not as above ....................................................................................................47
47a. Leaves with rounded petioles; bark greenish-brown that become gray-furrowed ......................Balsam Poplar
b. Leaves with flattened petioles especially where it attaches to leaf blade ....................................48
48a. Tree branches pointing sharply upward forming a columnar crown;
leaves diamond shaped and finely toothed ................................................................................Lombardy Poplar
b. Trees not columnar; leaves triangular, ovate or round .................................................................49
49a. Leaves broadly triangular and coarsely toothed; bark of trunk becoming
deeply furrowed and dark gray ...................................................................................................Eastern Cottonwood

b. Leaves not broadly triangular; twigs mostly brown to reddish-brown ........................................50
50a. Leaves finely toothed; bud scales shiny and smooth ..................................................................Quaking Aspen

b. Leaves coarsely toothed; bud scales dull and hairy .....................................................................Bigtooth Aspen
51a. Sap milky; some leaves with lobes ............................................................................................37
b. Sap watery; leaves not lobed .......................................................................................................52
52a. Leaves 2-ranked; young branches will lie flat on table with all leaves touching table ...............53
b. Leaves in more than 2 ranks; when young branches are on table,
leaves will project up, away from the table .................................................................................60
53a. Leaves round or heart-shaped; fruit a cluster of small spheres under
a long, slender leaf-like bract ....................................................................................................American Basswood

b. Leaves twice as long as wide ......................................................................................................54
54a. Bark of trunk with narrow, crowded, steep-sided corky ridges or warts; fruit
a small, green, single sphere that is purple when ripe, and with one pit ....................................Hackberry

b. Bark of trunk may be furrowed but lacks corky ridges; winged, dry fruit or nutlet ......................55
55a. Leaves usually unequal at base; fruit a samara ...........................................................................56

b. Leaves usually equal at base ........................................................................................................59
56a. Leaves 2" or shorter, usually toothed .........................................................................................Siberian Elm
b. Leaves over 4" long; doubly toothed ............................................................................................57
57a. Small twigs warty or corky-ridged; leaf upper surface smooth or nearly so ..............................Rock Elm
b. Twigs not as above; upper surface of leaves usually rough (this characteristic
is variable so check several leaves) ............................................................................................58
58a. Leaves folded along midrib; buds and twigs densely hairy .........................................................Slippery Elm

b. Leaves more or less flat; buds not hairy .......................................................................................American Elm

59a. Leaves about 2" long, usually toothed; fruit a samara .................................................................Siberian Elm

b. Leaves about 4" long, sharply doubly toothed; fruit a nutlet inside a papery sac
with the sacs attached to a central stem in dense clusters .............................................................Eastern Hophornbeam
60a. Buds covered by a single cap-like scale; leaves lance-shaped ...................................................61
b. Buds covered by several overlapping scales; leaves broader than above ....................................62
61a. Twigs greenish-gray to olive-brown; leaf stem with small glands .............................................White Willow
b. Twigs reddish-brown to orange, shiny and hairless; leaf stem without glands .............................Peachleaf Willow
62a. Fruit on drooping catkins that ripen in late spring .......................................................................63
b. Fruit apple-like or a sphere with one pit .......................................................................................64
63a. Leaves triangular and coarsely toothed .......................................................................................Eastern Cottonwood
b. Leaves usually ovate and finely toothed ........................................................................................Balsam Poplar
64a. Leaf stems with small glands; fruit a sphere with one pit ............................................................65
b. Leaf stems without glands; fruit apple-like ...................................................................................66
65a. Fruit yellowish and peach-like ...................................................................................................Apricot
b. Fruit small spheres attached in clusters and black when ripe .......................................................Black Cherry
66a. Fruit pear-shaped and yellowish; teeth of leaf edges ending in bristle-tips ................................Harbin Pear
b. Fruit apple-like; teeth of leaf edges not bristle-tipped ..................................................................Crab Apple

Modified by:
Dr. Erika Tallman, Northern State University, Aberdeen, SD 57401

Illustrated by:
Dorean Ball, student in Visual Arts Dept , SDSU, Brookings, SD 57007 Those drawings with DR were drawn by Dr. Diane
Rickerl, Plant Science Dept , SDSU Douglas fir cone was drawn by Adventura Design Agency, NSU.

Publication of the Key to South Dakota Trees fact sheet was funded by the S D Department of Agriculture, Division of
Forestry, Pierre, SD 57501