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Glossary

Showing 50 of 248 terms

Papillose
Bearing minute, pimple-like projections.

Pappus
In the Asteraceae, the modified calyx, usually consisting of a series of bristles, scales, or teeth.

Pedicel
The stem or stalk of an individual flower of an inflorescence or the stalk that supports a spikelet in grasses.

Peduncle
The stem or stalk of an inflorescence or a solitary flower.

Pendent
Hanging downward, drooping.

Perennial
Plant that lives for three or more years, producing leaves and stems each year from rootstock, crown buds, or branches.

Perfect
A flower that has both functional stamens and pistils.

Perfoliate
The bases of two opposite, sessile leaves are united around the stem so that the stem appears to pass through the leaf.

Perianth
The floral envelope, consisting of the calyx and corolla.

Perigynia
The inflated, sac-like sheath surrounding the pistil in Carex.

Petal
One part of the corolla. Often brightly colored and conspicuous. See drawing of flower parts.

Petiole
The stalk of a leaf. See drawing of leaf attachments.

Petiolule
The stalk of a leaflet in a compound leaf.

Phyllaries
Involucral bracts subtending the flower head in Asteraceae.

Pilose
Covered with long, thin, soft, distinct hairs. See pubescence drawings.

Pinnae
Primary division of a compound leaf.

Pinnate
A compound leaf with the leaflets arranged on both sided of the central axis. Odd pinnately compound leaves have a single leaflet at the end of the central axis. Even pinnately compound leaves have no leaflet terminating the central axis.

Pinnatifid
Divided pinnately into segments, but the segments are not distinct leaflets. Not cleft all the way to the rachis.

Pinnatisect
Pinnately cleft with sinuses extending nearly to the rachis.

Pinnule
Secondary segement of a compound blade.

Pistil
The female reproductive (seed-bearing) structure of a flower that receives the pollen. Flowers may have one to several pistils.

Pistillate
A flower bearing pistils but no stamens.

Pleurisy
Inflammation of the lungs causing a dry cough and painful breathing.

Pollen
The dust-like male spores in the anther.

Pome
A fleshy fruit of the apple type.

Poultice
A soft, moist pulp applied to sores and inflamed areas.

Prickle
Small, sharp spinelike outgrowth on the surface of a plant.

Primocane
In the genus Rubus, the first-year growth of a biennial stem that bears only leaves.

Prostrate
Lying flat on the surface of the ground. See drawing of stem forms.

Proximal
Situated near the point of attachment.

Pubescent
Covered with short soft hairs.

Raceme
A simple, elongated inflorescence with stalked (pediceled) flowers. See drawing of inflorescence types.

Racemose
A raceme-like branch of the inflorescence.

Rachis
The central axis of a spike or raceme inflorescence or pinnately compound leaf.

Resinous
Producing or containing a sticky secretion or sap.

Retrorsely
Bent or pointed downward, toward the base.

Retuse
A shallow notch at the rounded apex. See leaf apex drawings.

Revolute
Rolled backward, toward the lower side.

Rhizome
An elongated, underground, horizontal stem. See drawing of parts of a grass plant.

Root
The underground part of a plant that absorbs water, obtains and stores nutrients, and provides anchoring support in the soil.

Rosette
A circular and often flattened cluster of basal leaves radiating from a common point.

Sagittate
Arrowhead-shaped, with the basal lobes pointing downward or toward the petiole or stem.

Salverform
A slender-tubed corolla that expands at the top into a flat portion. See flower shape drawings.

Scabrous
Rough to the touch. Feels like sandpaper.

Scape
Leafless stalk arising from the ground or a basal whorl of leaves and bearing one or more flowers.

Scarious
Thin, dry, membranous, and somewhat translucent.

Schizocarp
A dry fruit that seperates into indehiscent, 1-seeded segments called mericarps.

Scientific Names
There are three parts to a plant's scientific name. The first part is the "genus", which is determined by similarities in morphology, flowering characteristics, or genetic relationships. The second part of the scienctific name is the "epithet". The genus and specific epithet together provide the name of the species. Species are also determined by similarities in morphology, flowering characteristics, or genetic relationships. The third part of the scientific name is the "authority". This is the person first credited with naming and describing the plant. Authorities appearing in parentheses had their work revised by a later plant taxonomist whose name follows. Sometimes species are divided into varieties, which is denoted by the abbreviation "var.". A scientific name that is no longer accepted is called a "synonym". Synonyms are indicated by an equal sign.

Secund
Directed to one side.

Sedge
A grass-like plant with a triangular stem often growing in wet areas. See drawing of plant group characteristics.