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Glossary   arrow

Achene — A small, dry, one-seeded fruit

Acuminate — Tapering gradually to a point.

Acute — Tapering rapidly to a point.

Alternate — Plant parts that are placed individually along a stem, in a zigzag arrangement, one leaf at each node, not opposite each other.

Angiosperm — A class of plants characterized by the formation of flowers and seeds enclosed in fruits.

Apex — The extreme top or tip of a plant part.

Appressed — Pressed closely and flatly along the length of a plant part.

Arcuate — Arching, as in leaf venation when veins arch from the midrib and follow the margin back to the tip of the leaf.

Axil — The upper angle formed by a leaf petiole with the stem.

Bark — The tissues formed on the outside of a woody stem.

Base — The bottom portion of an object.

Berry — A fleshy fruit without a stone, usually containing many seeds embedded in the pulp.

Bipinnate — More than one set of leaflets per leaf.

Blade — The flat, expanded portion of a leaf.

Bloom — White, powdery layer on plant parts. Usually easily rubbed off.

Branch — One of the divisions of the trunk.

Bristle — A stiff, thin hair which may be straight or hooked.

Bud — The undeveloped state of a branch, leaf and/or flower cluster, with or without hard scales.

Bud Scale — Modified leaves forming a covering which protects the bud from drying out and other injuries.

Bundle — A cluster of plant parts.

Bundle Scar — Marks within the leaf scar produced when the petiole separates from the stem, indicating the broken ends of the xylem and phloem strands.

Capsule — A dry fruit with many seeds, opening near the tip.

Catkin — A slender, pendulous, dense flower cluster.

Chambered — A solid pith that is interrupted by uniformly spaced partitions of hollow spaces.

Collateral — Being side by side, as in buds on a stem.

Compound — The leaf blade is divided into several separate sections called leaflets.

Concave — Depressed or hollowed out.

Conifer — A cone-bearing tree or shrub.

Continuous — Solid, no cavities or hollow spaces.

Convex — Arched

Cordate — Heart-shaped.

Crenate — A leaf margin with rounded, shallow teeth.

Crown — Upper part of a tree, the living branches with their foliage.

Deciduous — Plant having all leaves that fall off each year (fall).

Deltoid — Triangular.

Dentate — Sharp teeth of leaf margin pointed out, not forward.

Dissected — Finely divided.

Divergent — Bud stick out, point away from stem.

Downy — Plant part is coated with soft hairs.

Elliptic — Widest at the middle, tapering equally to each end.

Entire — Leaf edge (margin) has not indentations or teeth at all; completely smooth.

Evergreen — A woody perennial bearing foliage throughout the year.

Exfoliate — To peel or flake off in thin layers.

Flower — Reproductive organ of an angiosperm.

Fluted — Regularly marked by alternating ridges and grooved-like depressions.

Fruit — A ripened, mature ovary.

Furrowed — Longitudinal ridged and grooves.

Glabrous — No hairs, bristles, or scales. Smooth.

Gland — A tissue or protruding structure secreting oils, balsams, or resins; usually on a leaf or petiole.

Glaucous — Smooth and covered with a fine, white or blue powder (bloom) which can be rubbed off.

Globose — Round in form, or nearly so.

Granular — Minutely roughened.

Habit — General appearance of a plant as seen from a distance.

Herbaceous — Not woody; soft tissues.

Imbricate — Overlapping, like shingles on a roof.

Internode — The space between nodes that is lacking leaves and buds, such as on a stem.

Keeled — A prominent central ridge, like the keel of a boat.

Lanceolate — Tapering gradually from the base to a point; narrow and long.

Lateral — Situated or produced on the side.

Leaf — Appendage of a stem composed of a flat, veined blade, and a stalk attaching the appendage to the stem.

Leaf Scar — Scar left on the stem at the point where the leaf fell off.

Leaflet — One of the small, individual blades of a compound leaf.

Lenticel — A small breathing pore on the stem of plants, may be showing up as a different colored dot on the stem, somewhat corky.

Linear — Long and narrow with nearly parallel sides.

Lobe — Rounded or pointed extensions of the leaf blade margin.

Lustrous — Shiny, glossy.

Margin — The very edge of a leaf blade.

Midrib — The mid or central vein of a leaf.

Naked Bud — Lacking a covering, as in a bud with no protective hard scales.

Needle — Very narrow leaf, as in conifers.

Node — The place on a stem where buds and leaves arise, usually a swollen area on the stem.

Oblanceolate — Long and narrow but broadest near the tip.

Oblique — Lopsided.

Obovate — Egg-shaped, broadest near the tip.

Obtuse — Blunt at the tip, almost rounded.

Opposite — Plant parts arise opposite each other along a central axis.

Ovate — Egg-shaped, broadest below the middle.

Palmate — With divisions spreading from a common center.

Panicle — A branched flower cluster, the lower branches longest and flowering first.

Pendulous — Hanging down, drooping.

Persistent — Remaining attached, not falling off after the growth period.

Petiole — The leafstalk which attached the leaf blade to the stem.

Petiolule — The leafstalk of a leaflet in a compound leaf.

Pinnate — Leaflet or veins arranged on each side of a common stem; feather-like.

Pith — The central-most, softer portion of a stem.

Prickle — A needle-like outgrowth arising from the outer layer of stem, leaf or fruit cell (example: rose thorn).

Pubescent — Hairy or downy.

Rachis — The leafstalk of a compound leaf.

Reflexed — Abruptly bent or turned downward.

Resin — An excretion production of certain plants.

Reticulate — Net-like, many small irregular veins throughout a leaf.

Revolute — Rolled back toward the lower side, as in a leaf margin.

Root — Underground part of a plant which supplies the plant with nourishment, anchors the plant, and is a storage area.

Rugose — Coarsely wrinkled, uneven, rough.

Samara — A dry, winged, on-seeded, papery fruit.

Scabrous — Rough to touch.

Serrate — Leaf edge (margin) composed of teeth pointing toward the tip of the leaf.

Sessile — Without a stalk, sitting directly on the base.

Sheath — A tubular envelope, possibly papery, clasping and enclosing other plant parts, such as the needles of a pine.

Shoot — A stem bearing foliage.

Shrub — A woody perennial usually having many trunks.

Simple — In one piece; not divided into smaller units.

Sinus — The recesses or indentations between two lobes.

Spine — A sharp, thin modified leaf, arising form a node on the stem, just like a leaf would (example: cactus).

Spur Shoot — A short, stubby branch bearing leaves, flowers or fruit.

Stellate — Star-shaped.

Stem — The leaf and flower-bearing part of a plant.

Stipule — A leafy appendage at the base of a petiole, usually one at each side.

Stipule Scar — The scar left on the stem when the stipules fall off.

Stomata — Breathing pores in leaves.

Strobile — A small cone or cone-like structure.

Sub-opposite — Almost opposite, not quite.

Sucker — An extra shoot arising above ground from a root.

Superposed — One bud above another.

Tendril — A modified leaflet, leaf, stipule, or branch used as a lateral climbing organ by the plant.

Terete — Circular in cross section.

Terminal — Situated at the end or tip.

Terminal Bud Scar — The scar remaining on a stem after a bud has elongated and the bud scales have fallen off.

Thorn — A modified stem, hard and sharp-pointed, arising from a node (example: Hawthorn).

Tomentose — Densely woolly, hairy.

Tree — A woody perennial with one main trunk.

Trifoliate — Three leaflets, or leaves arranged in threes.

Valvate — Meeting at the edges, not overlapping

Vein — A strand of conducting tissue in a leaf. Continuation of the xylem and phloem from the stem, through the petiole, into the leaf.

Venation — Arrangement of veins within the leaf.

Whorl — The arrangement of leaves in groups of three or more at nodes.