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Midwestern Wetland Flora

Field Office Guide to Plant Species


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.
Anther
The pollen-producing part of a stamen.
Arcuate
Curved.
Auriculate
Bearing ear-shaped lobes.
Awn
A bristle-like process.
Bearded
With a tuft of hairs.
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.
Bractlet
A small bract.
Bristle
A stiff hair.
Calyx
All the sepals of a flower.
Capsule
A dry, dehiscent fruit splitting into 3 or more parts.

Cilia
Marginal hairs.
Ciliate
Bearing marginal hairs.
Clasping
Said of leaves that partially encircle the stem at the base.
Compressed
Flattened.
Connate
Union of like parts.
Cordate
Heart-shaped.
Composite
Referring to an inflorescence that is made up of many tiny florets crowded together on a receptacle.

Corm
An underground, tuber-like stem that stores food.
Corolla
All the petals of a flower.
Corymb
a type of flat-topped, branched inflorescence.
Crest
A small ridge.
Cyme
A type of inflorescence in which the central flowers open first.
Cymose
In the form of a cyme.
Deciduous
Falling off.
Dehiscent
Splitting at maturity.
Diaphragmed
Divided by partitions.
Disk
The central group of flowers in the head of the aster family; a fleshy growth that sometimes surrounds the ovary.
Drupe
A fruit with the seed surrounded by a hard, dry covering which, in turn, is surrounded by fleshy material.
Drupelet
A small drupe.
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.

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

Furrowed
Grooved.
Glabrous
Smooth.
Glaucous
Having a bluish appearance.
Globose
Round.
Glume
A sterile scale found in grasses
Hastate
Arrowhead-shaped, except that the basal lobes spread outward.
Hemispherical
Half-round.
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.
Involute
Rolled up lengthwise.
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.
Latex
Milky sap.
Lemma
A fertile scale found in grasses.
Lenticel
A small opening on a stem.
Ligule
A structure on the inside at the junction of the leaf blade and leaf sheath.
Linear
Elongated and uniform in width throughout.

Mucronate
With a short point sticking out the tip.
Node
That place on a stem where leaves and buds arise.
Nutlet
A small nut.
Obconic
Reverse cone-shaped.
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.

Pappus
Tufts of hairs attached to achenes of the aster family.
Peduncle
The stalk of an inflorescence.
Peltate
Attached at the middle.
Pendulous
Drooping.
Perennial
Living for 3 or more years.
Perforation
A circular opening.
Perianth
All the sepals and petals of a flower.
Perigynium
A sac-like structure enclosing the pistil in Carex.
Petiole
Leaf stalk.
Pinnate
Divided once along an elongated axis into distinct segments.

Pinnatifid
Divided nearly to the axis.
Pistil
The ovule-producing part of the flower.

Pith
The central, often soft, part of a stem.
Plumose
Feathery.
Prostrate
Lying flat on the ground.
Raceme
A grouping of flowers along an elongated axis where each flower has its own stalk.

Rachis
The axis of a flowering branch.
Ray
A flattened flower part in the aster family that is actually several petals fused together.
Receptacle
That part of the flower to which the sepals, petals, stamens, and pistils are usually attached.
Recurved
Curving downward.
Reflexed
Turned downward.
Reticulate
Like a net.
Revolute
Turned under along the edges.
Rhizome
An underground, horizontal stem.

Ribbed
Bearing ridges.
Rosette
A cluster of leaves around the base of the plant.
Samara
An indehiscent winged fruit.

Scale
A tiny, leaflike structure; the structure that subtends each flower in a grass or sedge.
Septate
With cross-walls.
Sessile
Without a stalk.
Setose
Bearing bristles.
Sheath
The base of a leaf that encircles the stem.
Sori
Structures found in ferns that contain the spore-producing sporangia.
Spadix
A fleshy axis in which flowers are embedded.
Spathe
A large bract subtending or sometimes enclosing a cluster of flowers.
Spatulate
Shaped like a spatula, broadest at the tip and tapering to the base.
Spike
A grouping of flowers along an elongated axis where each flower lacks a stalk.

Spikelet
A small spike.
Spinulose
Bearing small spines.
Sporangia
Structures that bear spores.
Spore
A microscopic reproductive body in ferns.
Spur
A slender, backward-pointing part of some flowers.
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.
Subglobose
Nearly round.
Succulent
Fleshy.
Superior
Referring to the position of the ovary when it is above the point of attachment of sepals, petals, stamens, and pistils.

Sutures
Seams; areas where splitting ocurs.
Tendril
A device, usually coiled, that enables some vines to climb.
Ternate
Divided into 3's.
Truncate
Cut straight across.
Tuber
A thickened, underground stem that stores food.
Tubercle
A wart-like process.
Umbel
A cluster of flowers in which the flower stalks arise from the same level.

Undulating
Wavy.
Valvate
Placed edge to edge.
Valve
The wing of the fruit in Rumex.
Whorl
The arrangement of 3 or more structures at a point on the stem.

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