A

Acorn—hard-shelled nut with pointed tip; found on oak trees

Alternate—arranged singly along a twig, branch, or shoot

Angled—with distinct ridges; not smoothly rounded

Aroma/Aromatic—producing a scent; fragrant

Axis (plural: axes)—central stalk of compound leaf or flower cluster

B

Bark—outer covering of trunk and branches

Bipinnate(ly)—leaflets arranged on side branches off of the main axis

Blade—broad and expanded part of the leaf

Blighted—affected by a blight, a bacterium, fungus, or virus that impairs growth

Bract—modified leaf structure that usually appears at the base of a flower (or their clusters) or a fruit (or fruits)

Branchlet—youngest and smallest part of a branch

Bristle tip—stiff hair at leaf tip

Bud—young (not developed) leaf, flower, or shoot frequently covered with scales

Bundle scar—small dots or lines found within the leaf scar when leafstalk is broken

Bur—prickly covering of seeds or fruit

C

Calyx—sepals of a flower

Cap—hardened, scaly top covering of an acorn

Capsule—dry fruit with 2 or more seeds

Catkin—small, unisexual flower or fruit cluster that is typically drooping and caterpillar shaped

Chambered (pith)—divided crosswise by plates

Cluster—bundled similar elements

Coarse-toothed—leaf edge with large teeth

Compound—leaf made up of 3 or more smaller leaflets

Cone—fruit with overlapping scales around an axis

Continuous (pith)—twig center not chambered or hollow

Cross-hatched—with sets of intersecting, parallel lines

Crown—the combination of branches, twigs, and leaves at the top of a tree that refers to a tree’s overall shape

Cultivated—planted and preserved by humans

D

Deciduous—losing foliage at the end of the growing season

Distribution—geographic range

Double-toothed—each tooth having smaller teeth

Dutch Elm Disease—disease caused by fungus, Ophiostoma ulm, and is passed through certain bark beetles or by grafting roots

E

Egg-shaped—ovately shaped and broader at the base than the tip

Elliptical—leaf shape that is widest in middle and tapers evenly to both ends; elongated oval

End bud, false—nearby bud that acts as an end bud when actual end bud is shed

End bud, true—bud or buds at the precise end of a twig

G

Girdle(d)—to remove a band of bark from a tree in order to kill it

Gland—small knob on a leaf’s surface that secretes a substance

H

Hayfever—allergic condition; symptoms frequently include sneezing, watery and itching eyes, and runny nose

Husk—shell or outer covering of some fruits and seeds

Hybrid—offspring that results in the cross of two different species

L

Lance-shaped—sharp-pointed

Lateral vein—vein that runs parallel to the natural curve of the leaf

Leaflet—leaflike subdivision of a compound leaf

Leaf base (or base)—lower portion of the leaf towards the leafstalk

Leaf scar—mark remaining on the twig or branch when a leaf falls or is removed

Leafstalk—stem that supports the leaf and connects it to the branches; also called petiole

Lenticel—corky, circular or stripelike spot on bark; pore for breathing

Lobe—leaf edge divided into separate, often rounded sections

Lowlands—areas that are low in elevation compared the surrounding areas

M

Maple sugar—sugar made from concentrated sap from Sugar Maple tree

Midvein—central vein of a leaf; also called midrib

N

Naturalized—introduced to foreign environment; adapted as if a native organism

Node—point where leaf, bud, or flower is attached

Nut—dry, 1-seeded fruit with thick and hardened shell

O

Oblong—elongated in form with parallel sides

Obovate—oval shape with broad tip

Opposite—arranged in opposing pairs along a twig

Ornamentation—decoration

Ovate—oval shape with broad base

P

Palmate(ly)—major veins spreading out to the edges from one point at the base of the leaf

Petal—brightly colored flower part; one of a group, often found in a circle

Petiole—Stalk that supports a leaf; leafstalk

Pinnate(ly)—with leaflet arrangement in 2 rows along main axis

Pith—spongy center tissue of a twig or stem

Pod—fairly dry, flat fruit containing one to many seeds

Pulp—part of fruit that is moist and soft

R

Resin—frequently aromatic plant secretion

Resin-dot—small, circular, yellow spots

S

Samara—dry, 1-seeded fruit with a wing; key

Sap—fluid that circulates through a tree

Saw-toothed—leaf edges that are divided into short, sharp-pointed protrusions

Scale—thin covering of a bud or acorn

Scaleless—without scales

Seed—part of mature fruit that house the embryo

Seed bed—area for growth

Sepal—part of flower that surrounds the reproductive organs; often green

Shoot—young twig or stem that is growing

Shrub—typically small plant with several stems growing from base; without single trunk

Side bud—bud in lateral position (on side of twig, not terminal or end bud)

Simple—made up of only one blade

Sinus—space between two leaf lobes

Species—group of individuals with small variation who interbreed

Spine—small, short woody growth emerging from twig or stem; a thorn

Sprout/Shoot—young plant growth

Spur branch—short side branch with dense, crowded leaves

Stalkless—without a leafstalk

Stamen—a male flower structure

Stipule—leaflike scale found at leafstalk base; frequently paired

Striation—parallel line

T

Tannin—chemical substance used for tanning and dye

Temperate—moderate weather conditions free from extremes

Thicket—areas with dense plant growth

Thorn—small, short woody growth emerging from twig or stem; a spine

Tooth (plural: teeth)—small, notched projection appearing along leaf edge

Trunk—major woody stem of tree

U

Untoothed—not toothed; without small projections along leaf edge

Uplands—areas of high elevation

V

W

Whorl—arrangement along twig or shoot that is in groups of 3 or more at each node

Wing—thin, flat, dry projection on fruit or seed

Wintergreen—distinct aroma, oil, or flavoring

F

Feather-compound—leaflets branching from a central vein at several points in featherlike arrangement

Feather-lobed—main lobes at right angles to midvein; pinnate-lobed

Fine-toothed—with small teeth

Fissure—long narrow crack or opening

Flower—reproductive structure of a tree or plant

Foliage—collective group of leaves

Fruit—seed-bearing part of a plant

K

Key—dry, 1-seeded fruit with a wing; a samara