Learn the Anatomy of a Tree

Tree Shape

Columnar: Tall and thin trees with upward facing branches.

Conical: Trees that are wider at the base and narrower at the top. Conical (also called pyramidal) trees have a distinct cone or pyramid shape with a triangular top. 

Crown: The foliage and branches at the top of a tree.

Habit: The term to describe the overall shape of a tree. Refers to the general mode of tree or plant growth.

Oval: The branches of the tree form an oval shape, spreading from the central trunk.

Round: The branches of the tree form a round shape, spreading from the central trunk.

Spreading: Wide trees with horizontally reaching branches.

Vase: Tree branches that grow upward at a sharp angle and that flare at the top, creating a wide crown.

Weeping: Tree branches droop downwards.

Foliage Type 

Conifers: Trees that are usually evergreen, have needle- or scale-like foliage, and bear cones. Commercial wood from conifers is often called softwood.

Deciduous: Trees that lose all of their leaves annually.

Evergreens: Trees that have foliage year round. Only the tree’s oldest leaves or needles fall each year.

Leaf Shape

Cunate: A leaf that has an acute angle base and is wedge-shaped.

Cordate: A heart-shaped leaf where the stem is attached at the wide end of the leaf (inversely indented).

Deltoid: A triangular-shaped leaf. The bottom two corners are usually rounded off.

Elliptical: An oval-shaped leaf. Its widest part is at its center and the two tips usually tapper equally.

Lanceolate: A leaf that is significantly longer than it is wide and has its widest section just below its middle.

Oblanceolate: A leaf that is significantly longer than it is wide and has its widest section just above its middle.

Oblong: A leaf that is longer than it is wide and has parallel sides. It may resemble a rectangle with rounded edges.

Obovate: An egg-shaped leaf where the widest part is above the middle of the leaf and the stem is attached to the narrow end.

Oval: A broadly elliptical (oval-shaped) leaf that has a width greater than half its length.

Ovate: An egg-shaped leaf where the widest part is below the middle of the leaf and the stem is attached to the wide end.

Round: A leaf that has a full sweeping arc base.

Spathulate: A leaf with a spatula-like shape. Its top is broadly rounded and its bottom curves downward toward the base.

Leaf Structure

Alternate: Leaves are staggered along the branch/twig (not directly across from each other).

Bipinnate: Leaves are attached on either side of the stem and the leaflets are also attached on either side of a stem (a two time subdivided pinnate arrangement).

Compound: Leaves are attached to a middle vein but also have their own stalks.

Even Pinnate (Paripinnate): Leaves are arranged in pairs along the stem without an extra leaf at the top.

Odd Pinnate (Imparipinnate): Leaves are arranged in pairs along the stem with one extra (pairless) leaf on top.

Paired: Leaves are arranged directly across from each other along the branch/twig.

Palmate: The blades, lobes, or veins of a leaf are arranged circularly or like fingers on the palm of a hand.

Pedate: The blades, lobes, or veins of a leaf are arranged like feet.

Pinnate: Leaves or the veins of a leaf that are arranged in pairs across from each other, or like the vanes of a feather. 

Bark 

Exfoliating: Bark that peels in shreds or thin layers.

Furrowed/Fissured: Bark with narrow openings or breakages.

Lenticels: Loosely packed mass of cells that appear on the bark as raised horizontal lines. Lenticels allow for gas exchange between the atmosphere and the interior tree tissue.

Ridged: Bark with narrow raised bands.

Fruit Types

Acorn: Comes from an oak tree

Berry: A fruit without a stone

Buckeye: Comes from a buckeye tree

Cone: Comes from a conifer

Drupe: Fleshy fruit with thin skin and central seed bearing stone

Pod: A case that holds a tree's seed

Samara: One seeded winged fruit

Flowers 

Anthers: The part of the stamen that contains pollen.

Bract: Part of the flower found above the leaves but below the flower. A modified leaf that bears a flower.

Catkin: Clusters of petalless flowers. Catkins are usually unisexual.

Dioecious: A flower that has male and female reproductive organs on separate flowers.

Monoecious: A flower that has both male and female reproductive organs on the same flower.

Panicle: A loosely branched cluster of flowers.

Racemes: Unbranched flower clusters where each flower grows on a small stalk, equally spread along a central stem.

Spike: A flower arrangement where the flowers are tall and unbranched.

Stamen: The male reproductive organ of a flower that produces pollen. The stamen is made up of the stem and the anther.

Soil 

Acidic: Soil that has a pH level of less than 7.

Alkaline: Soil that has a pH level of more than 7.

Clay: Soil that is very dense and resistant to water movement.

Loam: Soil that is comprised of about equal parts sand and silt and a little less clay. Loam is often considered the ideal gardening soil.

Sandy: Very porous soil.

Silt: Soil that is made up of small particles and minerals that are smaller than a grain of sand but larger than a clay particle. These particles and minerals are easily carried and deposited by water.