KEY AND GUIDE TO NATIVE TREES, SHRUBS AND WOODY VINES OF DALLAS COUNTY

by
NORMA STILLWELL
Dallas, Texas
April, 1939

PRINTED BY
PROCTOR-ADAMS PRINTING SERVICE
DALLAS, TEXAS

PREFACE

This simple key and guide to the woody plants—trees, shrubs and woody vines—which grow naturally in Dallas County, Texas, has been prepared to help beginners of any age in getting better acquainted with these leafy neighbors and friends. Woody plants offer one of the best places to begin a study of nature: first because there are but few kinds to learn in comparison with many other living forms—about 90 of these plants against estimated numbers for the county of about 300 birds, 500 to 1000 other flowering plants and over 25,000 insects; second, woody plants remain in one place, freely available for observation at any hour or season and year after year—if they escape human interference. And what more helpful link toward acquaintance with other interesting forms of natural life can be found than an intimate friendship with their mutual friends, the trees!

The distinctions between trees and shrubs or between shrubs and woody vines are often purely arbitrary, depending in part on age. A plant which grows at least twenty feet tall and usually (not always) has just one woody, self-supporting stem at the ground is considered a tree. A plant which rarely grows taller than twenty feet, in a given region, and usually has more than one woody stem rising from the ground is considered a shrub. The separation of herbs from woody plants divides those plants which usually die down to the ground each winter from those having woody stems which persist above ground year after year. Some ninety different woody plants are distinguished from one another and briefly described in this key and guide. Each description represents a single species with the exception of the cactus, yucca, red oaks and red haws; the differences between the various species of these plants are too complex for this brief manual.

Scientific names are included here, not with any thought that they should be memorized or that they need be used in ordinary conversation, but to avoid the possibility of misunderstandings such as often arise from some common names which are used by different persons to designate different plants. Many plants have more than one common name and often one common name is used for two or more quite unlike plants. Common names listed first are the ones considered more suitable.

The first part of the scientific name represents the genus (plural, genera), a degree of relationship or grouping smaller than the family but more inclusive than the species. The second name represents the species or specific kind of plant; species are occasionally divided into varieties (var.). The abbreviation following the scientific name stands for the name of the botanist who first described or named the plant, scientifically. L. stands for Linnaeus, “the father of modern botany”, who first used this double-name (binomial) system of scientific classification.

More extended descriptions and further information about these plants may be found in some of the reference books listed in the back of this booklet; many, if not all of them, are available in the Dallas Public Library. Only the more necessary technical words have been used and these are defined or illustrated herein. Although this booklet endeavors to include all the woody plants growing naturally in Dallas County, no doubt omissions and errors will be found and the author will be glad to be informed of them.

Grateful acknowledgement is made to Dr. W. M. Longnecker and Dr. E. P. Cheatum of the Department of Biology, Southern Methodist University, and to Dr. B. C. Tharp of the Department of Botany and Bacteriology, University of Texas, for their most helpful suggestions and criticisms. Although this booklet is based upon the field observations of the author and her husband, Jerry E. Stillwell, who assisted her in many ways, she has made free use of such technical information as was needed from the volumes listed in the bibliography.

The illustrations used in this publication were drawn for it by Alice Ferguson.

NORMA STILLWELL, Dallas, Texas.

Copyright 1939 by the author.

HOW TO USE THE KEY

This key is based chiefly on leaves and twigs, as they offer the easiest clues for identification, especially in this climate where leaves are present about three-fourths of the year. The best method of study is to carry this booklet to the woody plant or plants you want to know. If this is not convenient, have at least a leafy twig in hand. When collecting specimens for study (a large-paged magazine will do for carrying and pressing), notes should include the date and location, any peculiarities of the bark, nature of thorns if not on the specimen taken, color of twigs or any other features which might change in drying, flowers or seeds or any such extra clues which might help to find the right name for the plant. Small specimens of leafy twigs may be taken in suitable locations without endangering or damaging woody plants provided they are always cut, never torn from the branches.

The sizes as well as shapes of leaves are usually more typical on older plants or on the higher branches of trees. When either leaves or twigs are described as opposite, this condition will be found to be true for both, although sometimes the opposite member is missing; but leaflets (leaf-like units of a compound leaf) may sometimes be opposite when the complete leaves are not—the position of leaves, not leaflets, is used in this key. The terms rare, common or abundant are used to apply solely to Dallas County.

Begin with the numbers 1 in the key and decide which of these fits the woody plant whose name you are seeking. Turn to the key number following the 1 you have chosen and again choose between the two descriptions bearing the same number. Continue this process until you have reached the name of a plant. This name will be followed by some number above 200; turn to this number in the guide and see whether this more complete description fits. If each of your choices in the key has been correct you now know the name of your plant. If this description in the guide does not fit your plant, go over the key again, selecting this time the other choice at any number where you may have been in doubt.

Whenever it has been necessary to use an obscure or variable characteristic an effort has been made so to arrange the key that the right answer will be reached whichever the choice. That is why some plant names appear more than once in the key. If the following points are noted any careful observer should be successful in identifying the native woody plants of Dallas County by the use of this key. It will be found helpful in other regions where the native plants are similar to those of Dallas County.

1. Look carefully for thorns or prickles.

2. Notice anything unusual about the bark of trunk and branches—knotty, flaky, peeling, color, etc.

3. Try to choose mature leaves of typical shapes and sizes rather than the unusual ones.

4. Look for flowers, fruits or seeds on or under a tree or other woody plant. These may furnish just the confirmation you need to feel sure of the right name.

GLOSSARY

axil: the angle where a leaf stem joins a twig.

deciduous: losing its leaves in winter, not evergreen.

dioecious: bearing staminate, or male, flowers on separate plants from the pistillate, or fruit-bearing flowers; hence some plants of certain species never bear fruits or seeds.

fruit: that part of any plant which contains the seeds.

lenticel: air pore in the bark.

monoecious: bearing the two kinds of flowers on the same plant.

opaque: not admitting or transmitting light.

perfect: having both stamens and pistils in one flower, as most showy flowers have.

pistillate: possessing a pistil or pistils and lacking stamens; female, or fruit-bearing.

staminate: possessing stamens and lacking a pistil; male, or pollen-bearing.

translucent: admitting some light but not clear or transparent.

Spike

Cyme

Umbel

Panicle

Catkin

Twigs

Opposite

winter bud

leaf scar

Alternate

Flower Parts

anther

pistil

stamen

sepal

petal

Pea Shaped Flower

Elliptical

Acute Tip

Coarsely Serrate (toothed) Margin

Lobed

Rounded

Pointed

Oblong

Crenate Margin

Midrib

Ovate

Acuminate Tip

Notched Margin

Truncate Base

Linear

Heart

Serrate Margin

More than one main vein at the base

Sickle

Obovate

Doubly Serrate Margin

veins united near margin

Pinnate

odd leaflet

Palmate

Twice Pinnate

leaflet

KEY TO NATIVE WOODY PLANTS OF DALLAS COUNTY
Based Principally On Leaves

Numbers below 200 refer to the key,
above 200 to the guide (p. 20).

1. Leaves evergreen 2

1. Leaves deciduous 7

2. Leaves pinnately compound 71

2. Leaves not pinnately compound 3

3. Plants with very thick, fleshy, flattened, leaf-like stems, usually covered with many prickles prickly-pear cactus 269

3. Leaves not very thick and fleshy and not prickly except at tips 4

4. Leaves in large rosette close to ground 5

4. Leaves needle-like, not in rosettes 6

5. Leaves sword-shaped yucca 205

5. Leaves fan-shaped palmetto (rare) 203

6. Inner bark yellowish brown, berries light blue red cedar 201

6. Inner bark darker brown, berries larger and darker, purplish mountain cedar (rare) 202

7. Leaves simple 8

7. Leaves compound 67

8. Leaves and twigs alternate 9

8. Leaves and twigs opposite 54

Leaves Simple and Alternate

9. Leaves linear (long and narrow) 11

9. Leaves not linear 10

10. Leaves smooth and very glossy on both sides, broadly truncate at base, stems flattened cottonwood 207

10. Leaves not possessing all three characteristics as given in 10 above 12

11. Leaves usually less than ¾ inch wide, midrib yellowish and prominent on both sides willow 206

11. Leaves usually more than ¾ inch wide, midrib not yellowish nor prominent on both sides peach 239

12. Trunks or twigs with thorns or spines 13

12. Trunks and twigs without thorns or spines 18

13. Thorny vines greenbrier 204

13. Thorny trees or shrubs 14

14. Leaf margins entire (smooth) 17

14. Leaf margins not entire, variously serrate or toothed 15

15. Leaves either blunt at tip or shallowly lobed or cut, primary veins usually straight to margins, often doubly serrate red haws 232

15. Leaves pointed at tip, serrate, not cut or lobed, veins united or curving near margins 16

16. Leaf width more than half the length, leaf flat, glands, if present on leaf-stem near leaf, dark wild plum (tree) 237

16. Leaf width less than half the length, tending to fold lengthwise, usually two bright red glands on leaf-stem near leaf dwarf plum 238

17. Leaf smooth or glossy, tip pointed, juice of stem milky bois d’arc or Osage orange 226

17. Leaf wooly on under side, especially when young, usually rather blunt at tip, juice of stem not milky wooly bumelia, chittam wood or gum elastic 272

18. Leaves either lobed or coarsely toothed 33

18. Leaves neither lobed nor coarsely toothed, sometimes doubly toothed 19

19. Leaf margin serrate or crenate or doubly toothed 20

19. Leaf margin smooth or wavy 47

20. Vines rattan 261

20. Not vines 21

21. Leaf margins doubly toothed (large and small teeth) 22

21. Leaf margins not doubly toothed 25

22. Leaves 3 to 7 inches long, twigs not corky winged 23

22. Leaves 1 to 3 inches long, twigs sometimes corky winged 24

23. Inner bark mucilaginous (“slippery” when chewed), leaves rough above, downy below red or slippery elm 220

23. Inner bark not mucilaginous, leaves rather smooth above and downy below white or American elm 221

24. Leaves 1 to 2½ inches long, rather blunt tips, flowers in fall cedar elm 222

24. Leaves 1½ to 3 inches long, tapering point, flowers in spring winged elm (rare) 223

25. Bark of trunk with warty or knotty projections rough-leaved hackberry 224

25. Bark of trunk without warty projections 26

26. Leaf length more than 4 times width peach 239

26. Leaf length less than 3 times width 27

27. Larger twigs with whitish cross-streaks, flowers and fruit in catkin-like racemes wild cherry (rare) 236

27. Twigs without whitish cross-streaks, flowers and fruits not in racemes 28

28. Lowest pair of primary leaf veins much longer than others New Jersey tea 260

28. Lowest pair of primary leaf veins not much, if any, longer than others 29

29. Leaf veins and midrib yellowish and prominent on under side, primary veins closely and evenly spaced Indian cherry 259

29. Leaf veins and midrib not yellowish, if prominent on under side not closely and evenly spaced 30

30. Leaves 3 to 5 inches long (rarely much larger), sometimes mitten-shaped or, on young shoots, intricately lobed, margins rather coarsely serrate or toothed red mulberry 227

30. Leaves 1 to 3½ inches long, margins finely serrate or crenate, not lobed 31

31. Leaves 1 to 2 inches long, margins crenate, veinlets not conspicuous, twigs pale gray swamp holly 253

31. Leaves 2 to 3½ inches long, margins serrate, veinlets netted and conspicuous below, twigs purplish or reddish 32

32. Width of leaves more than half their length, flat, glands on leaf-stem dark wild plum (tree) 237

32. Width of leaves less than half their length, tending to fold lengthwise, usually 2 bright red glands on leaf-stem near leaf dwarf plum 238

33. Lobed or coarsely toothed leaves on vines 34

33. Lobed or coarsely toothed leaves not on vines 38

34. Leaf margins smooth, though sometimes slightly lobed 35

34. Leaf margins deeply lobed or coarsely toothed or both 36

35. Leaves 2 to 4 inches long Carolina moonseed (sarsaparilla) 229

35. Leaves 4 to 10 inches long Canada moonseed (very rare) 230

36. Leaf surfaces not downy or wooly 37

36. At least lower leaf surfaces somewhat wooly grapes 266 and 267

37. Leaves mostly 3-divided or deeply lobed or cut, fleshy cow-itch vine 264

37. Leaves coarsely toothed, not divided or deeply lobed, grapelike except thin and smooth, or nearly smooth Cissus ampelopsis 265

38. Leaves as broad as long sycamore 231

38. Leaves not as broad as long 39

39. Leaves toothed, not tough, rough above, not broader toward tip, often lobed on young trees red mulberry 227

39. Leaves tough, not rough above, lobed or notched 40

40. Leaves regularly notched but not deeply lobed 44

40. Leaves deeply lobed or else broader toward tip, not regularly notched 41

41. Lobes few and shallow or sharp-pointed at tips 42

41. Lobes not sharp-pointed at tips 45

42. Lobes, if any, few and shallow and near tip, leaves decidedly broader toward tip 43

42. Leaves with several to many sharp-pointed lobes, some of them always fairly deep, variously shaped, (more than one species) red oaks 219

43. Leaves 4 to 10 inches long black jack oak 218

43. Leaves 2 to 3 inches long water oak, duck oak or pin oak 217

44. Leaf notches pointed chinquapin oak 216

44. Leaf notches rounded swamp chestnut oak 215

45. Leaves 6 to 12 inches long bur oak 214

45. Leaves less than 6 inches long 46

46. Leaves 3 to 5 inches long post oak 212

46. Leaves less than 3 inches long scrub oak 213

Leaf Margins Smooth or Wavy, Not Lobed or Toothed

47. Vines 48

47. Not vines 50

48. Leaves 2 to 4 inches long Carolina moonseed 229

48. Leaves 4 to 10 inches long 49

49. Leaves deeply heart-shaped at base, wooly, leaf margin not extending beyond base of stem, not angled or lobed wooly pipevine 228

49. Leaves not always deeply heart-shaped at base, not wooly, leaf margin extending slightly beyond base of stem, leaves often angled or shallowly lobed Canada moonseed (very rare) 230

50. Leaves broad, at least nearly as broad as long, more than one main vein at base redbuds 240 and 241

50. Leaves decidedly longer than wide, one main vein at base 51

51. Leaves smooth or shiny above 52

51. Leaves not smooth, or shiny above southern hackberry 225

52. Leaf midrib and veins yellow and very prominent beneath, primary veins closely and evenly spaced, not branched Indian cherry 259

52. Leaf veins not very prominent beneath, not yellow, not evenly spaced 53

53. Leaves broader toward tip, sometimes lobed 43

53. Leaves not broader toward tip, not lobed persimmon 273

Leaves Simple and Opposite

54. Upper pairs of leaves often united around stem 55

54. Upper pairs of leaves not united around stem 56

55. A vine, leaves evergreen coral honeysuckle (rare) 282

55. A shrub, though some of stems long and straggling bush honeysuckle 283

56. Leaf margins entire or wavy 57

56. Leaf margins serrate or coarsely toothed 63

57. Leaves ½ to 1½ inches long 58

57. Leaves 1½ to 10 inches long 59

58. Leaves light yellowish green, glossy, narrowly oblong-obovate St. Andrew’s cross (sandy land) 268

58. Leaves dark green above, lighter and downy beneath, not glossy, ovate Indian currant 284

59. Leaves glossy above, often in whorls of three or sometimes more, midrib broad and yellow button bush 281

59. Leaves not glossy above, not in whorls, midrib not yellow 60

60. Leaves 7 to 10 inches long catalpa or cigar tree (rare) 279

60. Leaves less than 6 inches long 61

61. Twigs dark, with conspicuous light dots, primary veins not prominent below nor indented above, usually less than 2½ inches long swamp privet 277

61. Twigs without conspicuous light dots, primary veins prominent below and indented above, usually over 2½ inches long 62

62. Leaves smooth but not glossy above, tending to cluster towards ends of twigs flowering dogwood (rare) 270

62. Leaves rough above, distributed along branchlets dwarf or rough-leaved dogwood 271

63. Twigs bright green, often 4-sided or ridged, leaves smooth but not glossy, acuminate tips waahoo 254

63. Twigs neither green nor 4-sided 64

64. Leaves very glossy above black haw 285

64. Leaves not glossy above 65

65. Leaves 3 to 5 inches long, rather coarsely toothed French mulberry 278

65. Leaves ¾ to 3 inches long, finely serrate or crenate 66

66. Leaves blunt at tip spring herald 276

66. Leaves tapering at both ends swamp privet 277

67. Compound leaves alternate 68

67. Compound leaves opposite 91

Leaves Compound and Alternate

68. Trunks or twigs with spines or thorns 69

68. Trunks and twigs without spines or thorns 74

69. Low shrubs, 6 inches to 2 feet high pasture rose 234

69. Not low shrubs 70

70. Leaves with 3 to 5 leaflets 71

70. Leaves with more than 5 leaflets 72

71. Stems trailing, usually on the ground dewberries 235

71. Stems climbing prairie rose (rare) 233

72. Thorns long, often branched honey locust 243

72. Thorns or prickles short 73

73. Leaflets ovate and with odd leaflet at tip prickly ash 246

73. Leaflets oblong and without odd leaflet at tip mesquite 240

74. Vines 75

74. Not vines 78

75. Leaves twice-pinnately compound pepper vine 263

75. Leaves palmately compound or with 3 leaflets 76

76. Three leaflets 77

76. Five or more leaflets Virginia creeper 262

77. Leaves succulent (thick and juicy), sometimes three-lobed instead of parted cow-itch vine (rare) 264

77. Leaves not succulent, leaflets always fully parted, plant often shrubby when young poison oak or poison ivy 251

78. Leaves twice-pinnately compound chinaberry 248

78. Leaves not twice-pinnate 79