USGS - science for a changing world

Northern Prairie Wildlife Research Center

  Home About NPWRC Our Science Staff Employment Contacts Common Questions About the Site

Midwestern Wetland Flora

Illustrated Glossary of Floral Terms


Achene
A one-seeded, dry, indehiscent fruit with the seed coat not attached to the mature ovary wall.

Alternate
In reference to leaves: occurring at different levels successively on opposite sides of stem.

Annual
Living only for one year.
Auricle
An ear-shaped appendage to a leaf or stipule.
Awn
A bristle-like process.
Berry
A fruit with the seeds surrounded only by fleshy material.
Biennial
Living for two years.
Bract
An accessory structure at the base of some flowers, usually appearing leaflike.
Bracteole
A secondary bract.
Bristle
A stiff hair.
Capsule
A dry, dehiscent fruit splitting into 3 or more parts.

Ciliate
Bearing marginal hairs.
Clasping
Said of leaves that partially encircle the stem at the base.
Composite
Referring to an inflorescence that is made up of many tiny florets crowded together on a receptacle.

Corm
An enlarged, solid, rounded, underground stem, which is covered with a few thin scales or leaves.
Corolla
All the petals of a flower.
Cyme
A type of inflorescence in which the central flowers open first.
Dehiscent
Splitting at maturity.
Drupe
A fruit with the seed surrounded by a hard, dry covering which, in turn, is surrounded by fleshy material.
Ellipsoid
Referring to a solid object that is broadest at the middle, gradually tapering to both ends.
Elliptic
Broadest at the middle, gradually tapering to both ends.

Fibrous
Referring to a cluster of slender roots, all with the same diameter.
Filament
The stalk of a stamen.
Follicle
A dry, dehiscent fruit that splits along one side at maturity.

Glaucous
Having a bluish appearance.
Glume
A sterile scale found in grasses
Indehiscent
Not splitting open at maturity.
Inferior
Referring to the position of the ovary when it is below the point of attachment of the sepals and petals.

Inflorescence
A cluster of flowers.
Lanceolate
Lance-shaped; broadest near the base, gradually tapering to the narrower apex.

Lanceoloid
Referring to a solid object that is broadest near the base, gradually tapering to the narrower apex.
Lemma
A fertile scale found in grasses.
Linear
Elongated and uniform in width throughout.

Mucro
A sharp point at termination of an organ or other structure.
Nutlet
A small nut.
Oblanceolate
Reverse lance-shaped; broadest at the apex, gradually tapering to the narrower base.

Oblong
Broadest at the middle, and tapering to both ends, but broader than elliptic.

Oblongoid
Referring to a solid object that, in side view, is nearly the same width throughout.
Obovate
Broadly rounded at the apex, becoming narrowed below.

Obovoid
Referring to a solid object that is broadly rounded at the apex, becoming narrowed below.
Opposite
In reference to leaves: forming a pair opposite each other on the stem.

Orbicular
Round.

Ovary
That part of the pistil that contains the ovules.
Ovate
Broadly rounded at the base, becoming narrowed above; broader than lanceolate.

Ovoid
Referring to a solid object that is broadly rounded at the base, becoming narrowed above.
Ovule
Immature seed.
Palmate
Divided radiately, like the fingers of a hand.

Panicle
An arrangement of flowers consisting of several racemes.

Perennial
Living for 3 or more years.
Perianth
All the sepals and petals of a flower.
Perigynium
A sac-like structure enclosing the pistil in Carex.
Pinnate
Divided once along an elongated axis into distinct segments.

Pistil
The ovule-producing part of the flower.

Prostrate
Lying flat on the ground.
Raceme
A grouping of flowers along an elongated axis where each flower has its own stalk.

Receptacle
That part of the flower to which the sepals, petals, stamens, and pistils are usually attached.
Rhizome
An underground, horizontal stem.

Samara
An indehiscent winged fruit.

Scale
A tiny, leaflike structure; the structure that subtends each flower in a grass or sedge.
Spadix
A fleshy axis in which flowers are embedded.
Spathe
A large bract subtending or sometimes enclosing a cluster of flowers.
Spike
A grouping of flowers along an elongated axis where each flower lacks a stalk.

Spikelet
A small spike.
Stamen
The pollen-producing organ of a flower.

Stigma
The terminal part of a pistil.
Stipule
A leaflike outgrowth at the base of a leaf stalk.
Stolon
A horizontal stem lying on the surface of the soil.
Style
That part of the pistil between the ovary and the stigma.
Succulent
Fleshy.
Superior
Referring to the position of the ovary when it is above the point of attachment of sepals, petals, stamens, and pistils.

Terete
Nearly cylindrical in section.
Tubercle
A wart-like process.
Umbel
A cluster of flowers in which the flower stalks arise from the same level.

Valve
The wing of the fruit in Rumex.
Whorl
The arrangement of 3 or more structures at a point on the stem.

Return to Main Menu

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo USA.gov logo U.S. Department of the Interior | U.S. Geological Survey
URL: http://www.npwrc.usgs.gov/resource/plants/floramw/gloss.htm
Page Contact Information: Webmaster
Page Last Modified: Saturday, 02-Feb-2013 06:06:59 EST
Reston, VA [vaww54]