Raceme An elongated cluster of flowers on a stalk. This feature helps explain how flowers are arranged, how pollination happens, or how seeds begin to form.
Arboretum Botanical Glossary
A botanical reference guide of morphological terms, plant structures, propagation techniques, and campus flora definitions.
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Explore terms organized by botanical structure, morphology, and arboricultural concepts.
Rachilla The axis of a grass or sedge spikelet; a small rachis
Rachis The central rib of a compound leaf or flower cluster
Radiate Having parts radially arranged about a central point. This feature helps describe plant form, function, or identification.
Radical On or near the roots of a plant. This feature helps describe plant support, storage, water movement, or vegetative spread.
Ramose With many branches. This feature helps describe plant form, function, or identification.
Receptacle The part of a flower that holds all the floral structures together. It is located at the top of the flower stalk, where the petals, sepals, stamens, and carpels are attached. Did You Know? In some plants, the receptacle becomes part of the fruit. For example, the fleshy edible portion of a strawberry develops primarily from the enlarged receptacle, while the tiny "seeds" on…
Reniform Kidney shaped. This feature helps describe plant form, function, or identification.
Resin A sticky substance secreted by a plant. This feature helps describe plant form, function, or identification.
Resupinate Upside down, due to twisting of the pedicel, as in the flowers of some orchids