Southeast Exotic Pest Plant Council Invasive Plant Manual

Glossary of Botanical Terms

Achene: A small, dry, hard one-locular, one-seeded closed fruit with a thin pericarp, derived from a one-carpellate ovary.

Acuminate: Long-tapering to a pointed apex.

Adventitious: Buds or roots that develop without pattern.

Annual: Life cycle completed in one year or one season.

Axil: The angle found between any two organs or structures.

Biennial: Plant with life cycle completed in two years or seasons.

Bipinnate: A pinnate leaf with the divisions also being pinnate, twice pinnate.

Bracts: A reduced leaf, particularly one subtending a flower as the involucral bracts in Asteraceae.

Calcareous: Of the nature of, or containing, lime.

Calyx: The usually green, outer whorl or series of whorls surrounding flower petals.

Cauline: Pertaining or belonging to an evident stem or axis, as opposed to basal.

Ciliate: With hairs arranged on the edge of a flattened structure such as a leaf or petal.

Compound: Composed of two or more similar and united parts, as in a compound pistil or leaf.

Cordate: With a sinus or rounded lobe at the base.

Corolla: The inner, usually colored or otherwise differentiated, whorl or whorls of the perianth.

Corymb: Short, broad, more or less flat-topped indeterminate inflorescence, the outer flowers opening first.

Crenate: Shallowly round-toothed or teeth obtuse; scalloped.

Cuneate: Wedge-shaped; triangular, with the narrow end at the point of attachment, at the bases of certain leaves or petals.

Cyme: A broad, flattish determinate inflorescence, the central flowers maturing first.

Deciduous: Not persistent or evergreen.

Decumbent: Reclining or lying on the ground, but with the end ascending.

Dioecious: Having staminate and pistillate flowers on separate plants.

Drupes: A fleshy, usually one-seeded indehiscent fruit with seed enclosed in a stony endocarp.

Eciliate: Without hairs arranged on the edge of a flattened structure such as a leaf or petal.

Elliptic: Having narrow to relatively round ends and being widest at or about the middle, two-dimensional, essentially laminate.

Entire: A margin without teeth, lobes or divisions.

Glabrous: Without hairs, smooth.

Glaucous: Covered with a fine, waxy, removable powder that imparts a whitish or bluish cast to the surface.

Globose: Globular or spherical in shape.

Hirsute: With rather rough or coarse hairs.

Hymenopterous: Pertaining or belonging to an order of insects, Hymenoptera, having four membranous wings, comprising the wasps, bees, ants, etc.

Inflorescence: The flowering section of a plant.

Involucre: A whorl or collection of bracts surrounding or subtending a flower cluster or a single flower.

Lanceolate: Lance-shaped, much longer than wide, widened at or above the base and opening to the apex.

Lenticels: A lens-shaped, biconvex spot on the surface of a plant, which serves as a pore.

Mericarps: The individual, separated carpels of a schizocarp as in the Apiaceae or the "nutlets" in the Boraginaceae.

Monoecious: With staminate and pistillate flowers on the same plant.

Monotypic: Having only one representative, as a genus with a single species.

Non-ionic surfactant: A surface active agent that reduces the surface tension between it and another liquid not occurring in the form of ions.

Obtuse: Blunt, rounded at the end.

Odd-pinnate: Pinnately compound and with a terminal leaflet, so that typically there is an odd num-ber of leaflets.

Ovate: With an outline like that of a hen's egg, the broader end below the middle, having two dimen-sions.

Panicles: An indeterminate branching raceme; an inflorescence in which the branches of the primary axis are racemose and the flowers pedicellate.

Pedicel: The support of a single flower in a cluster, any stalk or stem between sepals and main axis.

Perennial: A plant living three or more years duration.

Perfect flowers: Bisexual; having both male and female sexual organs.

Petiole: The stalk by which a leaf is attached to the stem; leaf stalk.

Phytophagous: Herbivorous.

Pinnate: With the leaflets or pinnae of a compound leaf placed on either side of the prolongated peti-ole, feather-like.

Plumose: Feathery appearance often from long dense pubescence; the pappus of some Asteraceae.

Polygamous: Bearing unisexual and bisexual flowers on the same plant, or different individuals of the same species.

Pubescent: Covered with soft, short hairs.

Raceme: A simple, elongated, indeterminate inflorescence with pedicelled or stalked flowers.

Rhizome: Usually elongate, horizontal underground or subsurface stem, usually rooting at the nodes.

Samaroid: Like or as a samara; an indehiscent, usually one-seeded winged fruit, such as a maple or elm.

Schizocarp: A fruit that splits between carpels into two or more one-seeded portions, as in the Apiaceae or Boraginaceae.

Serrate: With sharp teeth pointing forward.

Sessile: Attached by the base without a stalk or stem.

Silique: The long slender fruit of certain Brassicaceae, much longer than broad.

Squarrose: Abruptly spreading or recurved at some point above the base.

Suborbicular: Circular or round on the under side or beneath.

Surfactant: Any substance that when dissolved in an aqueous solution reduces its surface tension between it and another liquid.

Terete: Cylindrical, usually solid or slightly tapering, and round in cross-section.

Terminal: Growing at the tip or end of a branch or stem, as in a bud or inflorescence.

Tomentose: Closely covered with down or matted hair.

Truncate: Square or broad at the end, not tapered, base or apex essentially straight across.

Tuberous: Having a fleshy enlarged portion of a rhizome or stolon with only vestigial scales; true tubers found in the Solanaceae.

Umbel: An inflorescence with pedicels or flower stalks or both, nearly equal in length and arising from a common point; umbrella shaped.

Whorl: Three or more leaves or flowers at one node in a circle.

References

Gleason, H. A.; Cronquist, A. Manual of vascular plants of northeastern United States and adjacent Cananda, 2nd Ed. Bronx, NY: The New York Botanical Garden; 1991.

Radford, A. E.; Ahles, H. E.; Bell, C. R. Manual of the vascular flora of the Carolinas. Chapel Hill, NC: The University of North Carolina Press; 1968.

Harris, J. G.; Harris, M. W. Plant identification terminology: an illustrated glossary. Spring Lake, UT: Spring Lake Publishing; 1994.