Dendrology 101 & Tree Identification Techniques

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1 Dendrology 101 & Tree Identification Techniques Presented by Craig Hensley, Park Interpreter Guadalupe River State Park Saturday, October 21 Texas Master Naturalist 18 th Annual Meeting

2 Step 1: Purchase a Field Guide Field Guide to Texas Trees by Benny J. Simpson Texas Trees Field Guide by Stan Tekiela Texas, Shrubs, and Vines of the Texas Hill Country by Jan Wrede Texas Trees: A Friendly Guide by Paul W. Cox & Patty Leslie Native and Naturalized Woody Plants of Austin & the Hill Country by Brother Daniel Lynch, C.S.C. Step 2: Become Familiar with it Review the Book particularly the coverage range and the descriptions/terminology Keep in mind that Texas has more than 5,000 vascular plants within its borders If you are going to get serious, a good jeweler s loupe will come in handy 10x is recommended

3 Dendrology: The Scientific Study of Trees and other Woody Plants Woody plants include trees, shrubs, bushes, sub-shrubs and vines The definition of a tree, according to Utah State University is a woody plant having one erect perennial stem (trunk) at least three inches in diameter at a point 4.5 feet above the ground, a definitely formed crown of foliage, and a mature height of at least 13 feet.

4 Transport The Tree as a System* ENVIRONMENT TREE FUNCTION STRUCTURE Carbon Dioxide Light Photosynthesis Leaves Support Branches Stems Shoot System Water Nutrients Stability Uptake Woody Roots Fine Roots Root System *From The Growing Tree by Brayton F. Wilson

5 Tree Growth Trees are dynamic systems Trees grow through using materials they produce leading to changes in thickness and length of each branch For trees to grow they must produce more photosynthate than they need to maintain themselves The difference in fast- vs. slow-growing trees or those of different species result not from different processes, but different rates of those processes

6 Keys to Identification of Woody Plants: 1. Deciduous vs. Evergreen 2. Bark 3. Silhouette 4. Twig Morphology 5. Flowers 6. Fruit 7. Leaf Characteristics a. Shape b. Margin c. Venation d. Pubescence/lack of e. Lobing/lack of f. Simple/Compound

7 Deciduous vs. Evergreen

8 Bark Characteristics

9 Basswood Elm Maple

10 Walnut Hickory

11 Live Oak Burr/Post Oak

12 Tree Buds Leaves, flowers, and/or stems emerge from the apical meristem deep inside a bud Tree buds are useful tools for tree identification, particularly during winter months for deciduous trees The orientation of the buds help determine the growth direction and thus shape of a tree By counting the bud scale scars on a branch, you can determine the age of that branch

13 Twig Morphology

14 Leaf Basics

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17 Leaf Margins

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21 Let s Practice

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29 Dichotomous (Taxonomic) Keys Used to sort out species of similar living things Design consists typically of couplets of choices, for example: 1: Plant with deciduous leaves; 1 : Plant with evergreen (needle-like) leaves Choosing one or the other leads to a new couplet for each Following this path leads you to the identification of the specific organism or thing

30 1 Plant evergreen or feathery and thin, fruit a cone 2 1 Plant deciduous Leaves tiny, sharp, scale-like; fruit a bluish cone (berry-like). Ashe Juniper 2 Leaves feathery, alternate to ¾ inches long; cone green turning brown..bald Cypress 3 Leaves opposite one another on branch or stem Leaves arranged alternately along branch or stem.14 4 Leaves compound 5 4 Leaves simple..9 5 Leaves palmately compound; 5 leaflets all attached at central location.yellow Buckeye 5 Leaves pinnately compound; not as above..6 6 Leaflets 3, entire, strong odor when crushed Wafer Ash (Hop Tree) 6 Leaflets 3 or more, if three leaflets, not entire. 7 7 Leaflets 3 to 5, coarsely toothed above middle, stems green...box Elder 7 Leaflets 5 or more Leaflets 9-10 pairs, leaflets toothed. Elderberry 8 Leaflets 5, margins entire. Green Ash

31 9 Leaves in whorls of three, margins entire... Buttonbush 9 Leaf opposite in pairs Leaves oval, finely toothed, rusty hairs on lower central vein Rusty Blackhaw 10 Leaves not as above Leaves with coarse teeth, upper surface rough..texas Lantana 11 Leaves entire Leaves small, diamond-shaped, entire, stems at 90-degree angle from stem..elbowbush 12 Stems and leaves not as above Leaves small, entire, oval, sometimes clustered. Whitebrush (Bee Brush) 13 Leaves larger, rough on upper surface, veins parallel or nearly so Rough Leaf Dogwood 14 Leaves compound Leaves simple Leaves twice compound Leaves only once-compound

32 Virginia Creeper

33 Basswood or Linden

34 Rough-leaf Dogwood

35 Mexican Buckeye

36 Slippery or American Elm

37 Box Elder

38 Poison Ivy

39 Sycamore

40 Cedar Elm

41 Sugarberry Hackberry

42 Blackjack Oak Spanish or Texas Red Oak

43 Shin Oak

44 Walnut

45 Redbud

46 Escarpment/Black Cherry

47 Honey Mesquite

48 Ashe Juniper

49 Thank you