Summer Tree ID Made EasySanford S. Smith, Ph.D. (“Sandy”)

Extension Specialist

Natural Resources and Youth Education

School of Forest Resources

Penn State Cooperative Extension

Tree ID, why?

DiagnosisManagement

Right ___ Right ___ Fun

Tree ID

Year ‘round

What can we use?

• Sometimes– Leaves– Flowers– Fruit

• All times (almost)– Bark– Location– Shape– Size– Shape– Smell– Taste

– TWIG!!!!

Leaf Terminology

Leaf Terminology

blade

leafmidrib

petiole

stipule

bud

stem

Simple Leaf

rachis

leaflet

petiolule

bud

Compound Leaf

Leaf Types

Broad and flat

Needles

Scale & awl-like

Leaf-type Comparison

Leaf Arrangement

Alternate

Opposite

Whorled

Leaf Arrangement Comparison

Leaf Structure

Compound Leaflet ArrangementsPalmately Compound

EvenPinnate

Bipinnately Compound

Leaf margins

Dentate

EntireDouble serrate

Lobed

Serrate

Leave the Leaves!

Fruit typesAchene

Acorn (nut)

Double and Single Samara

Nut

Legume

Capsule

Pome

Drupe

Berry

Tree Shapes

Branches: Pendulant Ascending

Willow White Oak

Parts of a twig

• Buds (scales, size, arrangement)

• Leaf scars (shape, size, vascular bundle scars)

• Stipule scars (presence, size)

• Lenticels (visibility)

• Pith (cross section shape & longitudinal appearance)

Pith types

Bud T

ypes

Identification Time

Tree ID with a Key to the Leaves

One decision at a time

Identification keys

• Dichotomous key

– most common type of key– simplistic and complex use– one decision at a time– On-line example

4-H Summer Key to PA Trees

Direct Online Link:

http://downloads.cas.psu.edu/4H/Summerkeyfortrees.pdf

Leaf Terminology

blade

leaf

petiole

bud

stem

Simple Leaf

rachis

leaflet

petiolule

bud

Compound Leaf

Leaf Arrangement Comparison

Lets practice!

Hint: opposite

Red MapleAcer rubrum

Red Maple

Hint: opposite

Sugar MapleAcer saccharum

Sugar Maple

Hint: alternate

Northern Red OakQuercus rubra

Northern Red Oak

Hint: opposite

Horse Chestnut Aesculus hippocastanum

Horse Chestnut

Eastern HemlockTsuga canadensis

Eastern Hemlock

Hint: lvs. alternate, sap not milky

Black LocustRobinia pseudoacacia

Black Locust

Hint: opposite

Flowering DogwoodCornus florida

Flowering Dogwood

Hint: alternate

White OakQuercus alba

White Oak

White Oak Red Oak

Hint: alternate

American BeechFagus grandifolia

American Beech

(one bundle joined by a small papery sheath at base)

Eastern White PinePinus strobus

Eastern White Pine

Clue: alternate, sap not milky

Bitternut HickoryCarya cordiformis

Bitternut Hickory

Hint: opposite

White Ash

Hint: alternate / hairy

Yellow Birch Betula alleghaniensis

Yellow Birch

Hint: alternate/hairySweet (Black) Birch ID Slide

Sweet (Black) BirchBetula lenta

Sweet (Black) Birch

Eastern RedcedarJuniperus virginiana

Eastern Redcedar

Hint: lvs. alternate, rough, and hairy

American ElmUlmus americana

American Elm

Hint: 3 lvs. shown, alternate

SassafrasSassafras albidum

Sassafras

Hint: lvs. alternate

Sweetgum Liquidambar styraciflua

Sweetgum

Hint: lvs. alternate, milky sap in leaf stalk

Norway MapleAcer platanoides

Norway Maple

Hint: leaves do not have stalks

Balsam FirAbies balsamea

Balsam Fir

Norway SprucePicea abies

Norway Spruce

Balsam Fir Norway SpruceFir versus Spruce

Hint: lvs. alternate, not hairy, margins have fine teeth; leaf stalks have glands.

(Single leaf) (Branch)

Black CherryPrunus serotina

Black Cherry

Hint: lvs. alternate, sap not milky, leaves hairy

Black WalnutJuglans nigra

Black Walnut

American LarchLarix laricina

American Larch

Hint: lvs. alternate

Yellow-poplar Liriodendron tulipifera

Yellow-poplar

Hint: lvs. alternate, milky sap

Smooth SumacRhus glabra

Smooth Sumac

•Prepared by Paul Roth, Former Research Assistant, Rance Harmon, Former Extension Associate, and Sanford Smith , Forest Resources Extension Specialist, The Pennsylvania State University, School of Forest Resources & Cooperative Extension

Acknowledgements•Idea development and review: Jason Hall, Sandra Insalaco, and Cecile Stelter – Service Foresters – Pennsylvania Department of Conservation and Natural Resources, Bureau of Forestry

•Review: James Finley, The Pennsylvania State University School of Forest Resources & Cooperative Extension

•Images provided courtesy of Virginia Tech & The University of Wisconsin.

•Line art courtesy of The Pennsylvania State University College of Agricultural Sciences and the Pennsylvania 4-H Program

References•Common Trees of Pennsylvania, Department of Conservation & Natural Resources, Bureau of Forestry

•The Audubon Society Field Guide to North American Trees Eastern Region, Knolph, Alfred A. Inc. 1980

•Virginia Tech Dendrological Web Page, www.fw.vt.edu/dendro/dendrology/main.html

•University of Wisconsin, botanical images, www.wisc.edu/botit/dendrology/names.html

•Textbook of Dendrology. Harlow, Harrar & White. 1978. McGraw-Hill Book Company

•Manual of Woody Landscape Plants. Dirr.Penn State is committed to affirmative action, equal opportunity, and the diversity of its workforce.

© The Pennsylvania State University, 2009

Sanford S. Smith (“Sandy”)

sss5@psu.edu1-800-235-9473

Penn State is committed to affirmative action, equal opportunity, and the diversity of its workforce