RACEME:An unbranched inflorescence of stalked flowers.
RACHIDIAN: Of or pertaining to a rachis.
RACHILLA: A secondary stem or axis of a spikelet in grasses and sedges.
RACHIS: That portion of an inflorescence, above the peduncle, bearing flowers.
RADIATE: 1. Spreading outward in a wheel shape from the center, as leaves around a stem. 2. Bearing ray flowers, as do many members of the Daisy family, Compositae.
RADICAL: Pertaining to or growing from the root.
RADICATE: 1. To take root. 2. To cause to take root; to plant deeply and firmly.
RADICICOLOUS: Living upon or in roots.
RADICLE: The initial root of an embryo or seedling.
RADICULOSE: Producing numerous rootlets.
RADIX: The root of a plant.
RAISED BED: A raised area for growing plants, usually enclosed by landscape timbers, in which the growing medium can be accurately determined.
RAMENTACEOUS: Covered with, consisting of, or resembling ramentum (See below).
RAMENTUM: A thin, brownish, fringed scale that appears on the young shoots or leaves of many ferns.
RAMICAUL: The leafy stem of some sympodial Orchids, such as those in subtribe Pleurothallidinae; distinguished from the rhizome.
RAMOSE: Branched; having many branches.
RAMULIFEROUS: Having many small branches.
RAMULUS: A small branch or branchlet.
RAPHE The part of the supporting stalk of an ovule that is fused to its outer covering. It is usually shaped like a ridge.
RAY: 1. One of the flower stems in an umbel, a flower cluster in which all such stems arise from the same point. 2. A daisy-like or ray flower.
RAY FLOWER: One of the petal-like parts of the flowers of many of the Compositae (Daisy family), such as the Sunflower and Aster.