Basal
Beginning from the lower extremity of a plant part, as in leaves from the base of a stem.
Base
The bottom; the proximal (nearest the stem) portion of a leaf (See also Apex).
Bipinnate
Referring to a compound leaf where the pinnate leaflet has subdivided into smaller leaflets giving a more feather-like appearance.
Blade
In trees, shrubs, vines and grasses, blade refers to the individual leaf; often referred to as Lamina.
Bloom
White or waxy coating on the surface; also referred to as being glaucous.
Bract
A modified leaf that is frequently showy and thought of as part of a flower; appears below actual flowers.
Branch
A secondary stem that forks off of the main stem or trunk.
Branchlet
A diminutive version of a branch; a small branch-like twig.
Broad-oval
An ellipse that is less than twice as long as it is wide; Used often for habit and leaf but can be used for other descriptions.
Broad-pyramidal
Pyramid shaped or triangular with a wider base than pyramidal.
Broad-rounded
Nearly circular, but wider than tall.
Bud
The unexpanded next season’s growth of leaves and flowers; undeveloped leaves and shoots.
Bud Scale
One of the sheaths that cover a bud; There can be a few to very many;
Bulbous
A tree bud that is rounded or ‘bulb-like’.
Bullate
A raised blistered appearance between veins. Tissue near veins appears to pucker.
Bundle Scar
Refers to the vascular bundles that are found in the scar left behind on a stem after a leaf falls off (abscises).