Leaf Presentations Review Material

Step 1: Tree Type When identifying trees, you will need to determine whether they are conifers or deciduous trees. --Gymnosperms are a taxonomic class that includes plants whose seeds are not enclosed in an ovule (like a pine cone). Gymnosperm means as "naked seed". This group is often referred to as softwoods. Gymnosperms usually have needles that stay green throughout the year. Examples are pines, cedars, spruces and firs. Some gymnosperms do drop their leaves - ginkgo, dawn redwood, and baldcypress, to name a few.

Conifer Examples

Tree Type Angiosperms are a taxonomic class of plants in which the mature seed is surrounded by the ovule (think of an apple). This group is often referred to as hardwoods. Angiosperms are trees have broad leaves that usually change color and die every autumn. Oaks, maples and dogwoods are examples of deciduous trees. Some angiosperms that hold their leaves include rhododendron, live oak, and sweetbay magnolia.

Angiosperm

Step 2: Branching Pattern Leaves either grow on opposite or alternate sides of a twig. If they are growing on opposite sides of a twig, there is a very good chance that the tree is a maple, ash or dogwood. Buds will also be on opposite or alternate sides of a twig. This is very helpful during winter tree identification

Mad Dog Chases a Buckeye!

Leaf Parts Major parts we need to know are Apex: tip of leaf Petitole: Stalk Midrib(vein): Central Blade: expanded portion Stipule: A growth at base of petitole, leaves scars on the twig when dropped

Simple Leaves have a single leaf blade. Step 3: Leaf Types Individual leaves can also be classified as either simple or compound (several to many leaflets per leaf) Simple Leaves have a single leaf blade.

Actually this type of compound is know as pinnately compound. Step 3: Leaf Types Compound leaves have several leaflets attached to a midrib or rachis.  The rachis is not particularly woody and no buds occur at the base of the leaflets. Actually this type of compound is know as pinnately compound.

Step 4: Margins Leaf margins (the edge around the leaf) can have many different forms. When tiny to large coarse teeth are present along the margins it is said to be Serrate. Serrate comes in many forms such as fine, coarse, single, or double toothed but for us we’ll just define it as serrate.

Step 4: Margins Other trees have lobed leaves; that is, the blade is divided into lobes by shallow to deep notches. The parts of the blade that extend from the leaf are called lobes the indentations are called sinuses. Sometimes Lobes and serrate come in combination too!

Step 4: Margins If the margin of the leaf is smooth and unvaried the leaf is said to be entire.

Step 5: Vein Patterns or Compound Patterns The pattern the veins make in a leaf can described commonly as either; *Pinnate (arcuate) *Palmate Parallel Reticulate

Step 5: Vein Patterns or Compound Patterns For our purposes we’ll use only pinnate and palmate with arcuate falling under pinnate. Compound leaves fall under these descriptions too but all of our leaves will be pinnately compound.

Step 6: Basic Leaf Shapes Egg or Ovoid Elliptical or Oval Lanceolate

Step 6: Basic Leaf Shapes Feather Lobed or pinnately lobed Fan-lobed or Palmately Lobed Heart Shaped or Cordate

Step 6: Basic Leaf Shapes Narrow or linear Wedge or Obovate Acicular

Step 6: Conifer Leaves Leaves can grow on conifers as either scales, single needles, or in groups called fascicles. Cedar leaves grow as scales.  Spruces, firs, hemlocks as well as others grow single needles.  Pines grow needles in fascicles. Remember the shape is usually considered acicular for the needles

Step 6: Conifer Leaves Scales Single-Needle # needles per fascicle

Dog Wood Margins - Entire Veination - Pinnate Type - Simple Shape - Egg

Loblolly Pine Needles in Cluster 3 Length 5-7 inches

Red Bud Margins - Entire Venation - Palmate Type - Simple Shape - Heart

Willow Oak Margins - Entire Veination - Pinnate Type - Simple Shape - narrow

Walnut Margins - Serrate Veination - Pinnate Type - Pinnately compound Shape - Oval

Winged Elm Margins - Serrate Veination - Pinnate Type - Simple Shape - Elliptical

Sweet Gum Margins - Serrate and Lobed Veination - Palmate Type - Simple Shape - Fan

Eastern Red Cedar Scales

Red Maple Margins - Serrate and Lobed Veination - Palmate Type - Simple Shape - Fan

Crape Myrtle Margins - Entire Veination - Pinnate Type - Simple Shape - Elliptical

White Oak Margins - lobed Venation - Pinnate Type - Simple Shape - Feather

American Beech Margins - Serrate Veination - Pinnate Type - Simple Shape - Elliptical

Tulip Poplar Margins - Lobed Veination - Pinnate Type - Simple Shape - Fan

Short Leaf Pine Needles to a cluster Two Size 3-5 inches

Scarlet Oak Margins - Serrate and Lobed Veination - Pinnate Type - Simple Shape - Feather

American Holly Margins - Serrate Veination - Pinnate Type - Simple Shape - Elliptical

Black Cherry Tree Margins - Serrate Veination - Pinnate Type - Simple Shape - oval

Butternut, Sand Hickory Margins - Serrate Veination - Pinnate Type - Pinnately Compound Shape - Elliptical

Northern Red Oak Margins - Serrate and Lobed Veination - Pinnate Type - Simple Shape - Feather

Sourwood Margins - Serrate Veination - Pinnate Type - Simple Shape - elliptical, narrow

Water Oak Margins - Entire Veination - Pinnate Type - Simple Shape - Wedge

Southern Magnolia Margins - Entire Veination - Pinnate Type - Simple Shape - narrow

Black Gum Margins - Entire Veination - Pinnate Type - Simple Shape – oval, Elliptical

Ash Margins - Serrate Veination - Pinnate Type - pinnately compound Shape - narrow

Post Oak Margins - Lobed Veination - Pinnate Type - Simple Shape - Feather

Southern Red Oak Margins - Serrate and Lobed Veination - Pinnate Type - Simple Shape - Feather

White Pine Five needles to a cluster soft needles 3-5 inches long

Southern Sugar Maple Margins - Serrate and Lobed Veination - Palmate Type - Simple Shape - Fan

Sycamore Margins - Serrate and Lobed Veination - Palmate Type - Simple Shape - Fan

Mimmosa Margins - Entire Veination - Pinnate Type - Bipinnatelycompound Shape - narrow

American Elm Margins - Serrate Veination - Pinnate Type - Simple Shape - Elliptical

River Birch Margins - Serrate Veination - Pinnate Type - Simple Shape - egg, oval

Black Oak Margins - Serrate and Lobed Veination - Pinnate Type - Simple Shape - Feather Fuzzy Leaf

Willow Tree Margins - Serrate Veination - Pinnate Type - Simple Shape - narrow