Pennsylvania Forest Stewardship Program: Identifying Pennsylvania Trees

Overview

• Objective: Help individuals learn to identify common Pennsylvania trees using the Summer Key to Pennsylvania Trees.
• Materials: Images and suggested narrative available as a PowerPoint presentation.
• Prepared by: Paul Roth & Rance Harmon from The Pennsylvania State University.
• Sponsors: Pennsylvania Bureau of Forestry & USDA Forest Service.

Tree Identification Basics

• Factors for Identification:
  • Leaves
  • Bark
  • Twigs
  • Buds
  • Flowers
  • Fruits
• Focus: Leaves for tree identification.

Leaf Types

• Scale-like: Thin, flat, closely appressed as in Arbor-vitae.
• Broad and Flat: Common in many deciduous species.
• Needles: Sharp or blunt as in pines, spruces, Eastern Hemlock.

Leaf Arrangement

• Alternate: Petioles staggered along the stem.
• Opposite: Two leaves attach directly across from each other.
• Whorled: Three or more leaves at the same point.

Leaf Structure

• Simple Leaf: Not divided into leaflets.
• Compound Leaf: Divided into leaflets (Pinnately & Palmately compound).

Leaf Margins

• Types:
  • Serrate: Sharp, forward-directed teeth.
  • Double Serrate: Each tooth bears small teeth.
  • Dentate: Teeth point outward.
  • Lobed: Large, rounded projections.
  • Entire: No teeth or lobes.

Tree Identification Using the Key

• Errors in Key: Check for updates if key is older than 2002.
• Identification Examples:
  • Red Maple (Acer rubrum): Opposite leaves, 3-5 lobes, coarsely toothed.
  • Sugar Maple (Acer saccharum): Opposite, simple, 5-lobed.
  • Flowering Dogwood (Cornus florida): Opposite, smooth margins.
  • Northern Red Oak (Quercus rubra): Alternate, simple with bristle-tipped lobes.
  • White Oak (Quercus alba): Alternate, simple with rounded lobes.

Notable Trees and Features

• American Beech (Fagus grandifolia): Alternate, stiff leaves with sharp-toothed margins.
• Yellow Birch (Betula alleghaniensis): Alternate, simple, doubly-toothed.
• Sweet Birch (Betula lenta): Alternate, simple, unevenly saw-toothed.
• Eastern Hemlock (Tsuga canadensis): Evergreen needles.
• Eastern White Pine (Pinus strobus): Needles in clusters of five.

Additional Tree Details

• Horse Chestnut (Aesculus hippocastanum): Opposite, palmately compound.
• Red Pine (Pinus resinosa): Clusters of two needles, dark green.
• Pitch Pine (Pinus rigida): Clusters of three stiff needles.
• American Elm (Ulmus americana): Alternate, rough upper surface.
• Black Walnut (Juglans nigra): Compound, alternate with many leaflets.

Unique Features

• Sassafras (Sassafras albidum): Aromatic leaves in various shapes.
• Tulip Poplar (Liriodendron tulipifera): Large, with four-lobed leaves.

Resources

• References: Common Trees of Pennsylvania, Field Guides, and University Websites.
• Acknowledgements: Contributions by forestry experts and institutions.

This summary captures the essence of the tree identification presentation, covering the key aspects of identifying trees using their physical characteristics. The presentation is a resourceful guide for educators and enthusiasts in Pennsylvania to understand and identify local trees effectively.