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Glossary

Showing 50 of 248 terms

Abaxial
The surface or portion of a lateral structure away from the bearing axis; the lower surface

Achene
Small, dry, one-seeded fruit. See drawing of fruits.

Acuminate
Gradually tapering to a sharp point. See leaf apex drawings.

Acute
Abruptly terminating in a sharp point. Less tapering than acuminate, i.e. at a sharper angle. See leaf apex drawings.

Adaxial
The surface or portion of a lateral structure toward the bearing axis; the upper surface

Aerole, Areola
1. small space on a surface, usually in reference to a space bounded by veinlets on a leaf surface; 2. small, spine-bearing area on a cactus.

Alternate
Leaves placed singly one above the other, usually on alternate sides of the stem. See drawing of leaf arrangements.

Annual
A plant that lives only one year or season. The plant must grow from seed each year.

Anther
The part of the stamen which contains pollen. See drawing of flower parts.

Anthesis
Flowering, or the point in time when pollination takes place.

Antrorse
Directed upward or toward the apex.

Apiculate
Ending in a small, flexible, short-pointed tip. See leaf apex drawings.

Arachnoid
Resembling a spiderweb or cobweb.

Aril
An appendage growing on a seed in the area of the hilum.

Arillate
Having an aril.

Aristate
Possessing a long, narrow apex or apex with a short awn or bristle .

Ascending
Sloping or angled upward. See drawing of stem forms.

Attenuate
Gradually narrowing to a long, slender point, more extreme than acuminate.

Auricle
Small ear-like projections. Found at the junction of the blade and the sheath in grasses. See drawing of parts of a grass plant.

Awn
A slender, stiff, bristle-like extension of a plant part, such as the beard on wheat. See drawing of parts of a grass plant.

Axil
The angle formed between two plant parts. Usually refers to the upper angle between a leaf and stem.

Barbellate
Having barbels (short, straight bristles).

Bearded
Having long or stiff hairs arranged in a row or tuft.

Berry
A fruit that is fleshy throughout.

Biennial
A plant which completes its life cycle in two years. Usually has leaves and stores food in underground parts the first year and then blooms, produces seeds and dies the second year.

Bifid
Two-cleft.

Blade
The flat, expanded part of a leaf that is above the sheath and away from the stem. See drawing of parts of a grass plant.

Bract
A reduced or modified leaf, often below a flower or flower cluster.

Bulb
An underground leaf bud enwrapped in fleshy scales or coats.

Bunch grass
A grass that forms a more or less circular, compact bunch.

Caducous
Falling off early.

Callus
Hard, downward extension of a mature lemma.

Calyx
The outer part of the floral envelope (perianth). Composed of the sepals and usually green in color. A collective term for the sepals.

Canescent
A fine, gray or white pubescence.

Cathartic
A substance that purges or cleanses, usually in reference to the bowels

Catkin
Long, spike-like inflorescence of small unisexual flowers without petals, each flower subtended by a bract.

Cauline
Borne on the stem, rather than basally.

Chasmogamous
Flower that is open at time of pollination.

Ciliate
Fringed with hairs on the margin.

Clasping
Surrounding or partially wrapping around a stem. See drawing of leaf attachments.

Cleistogamous
Small flowers that remain closed and are self-pollinated.

Collar
The portion of a grass leaf where the sheath and blade join.

Connate
Fused to a like part, such as petals fused to petals.

Connivent
Coming together but not actually fused.

Cordate
Heart-shaped , with the point upward. See drawing of leaf shapes.

Corm
Short, solid, bulb-like underground stem that produces leaves and flowering stalks.

Corolla
The inner part of the floral envelope (perianth), immediately surrounding the stamens. Composed of petals and often brightly colored. A collective term for the petals.

Corymb
A flat-topped or convex flower cluster with the outer flowers blooming first. See drawing of inflorescence types.

Crenate
Rounded, shallow teeth or scalloped.

Culm
The stem or stalk of a grass or sedge. Usually has a seed head at the top.