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Local Flora I: Spring
Grasslands | |
Plant Parts |
Monocots | Liliaceae | Other Monocot spp. | | Dicots | Ranunculaceae | Other Dicot spp.
Flower Morphology | Inflorescence Glossary
The flower is the basic reproductive unit of the flowering plant. Important characters for identification include presence or absence of floral series, the number of floral parts and their insertion.
From: Taxonomy of Flowering Plants, C.L. Porter (University of Wyoming), W.H. Freeman and Company, San Francisco.
Inflorescence Glossary - Arrangement of flowers
An inflorescence is an arrangement of one or more flowers on a floral axis. The number of flowers, their positional relationships, the degree of development of their pedicels, and the nature of the branching pattern within the flower cluster determine the particular inflorescence type.
Panicle: is a more or less elongated inflorescence with a central axis along which there are branches that are themselves branched. There may be a sequence of blooming from the base upwards.
Raceme: is an elongated inflorescence with a central axis along which are simple pedicels of more or less equal length. The order of blooming is usually from the bas up, but some racemes have flowers opening almost simultaneously or irregularly.
Spike: is an elongated inflorescence with a central axis along which are sessile or subsessile flowers. The usual order of blooming is from the base upward. Very small spikes, particularly in grasses and sedges, are known as spikelets. These may be grouped into various arrangements such as panicles, racemes, or spikes.
Corymb: is a more or less flat-topped inflorescence having a main vertical axis and pedicels or branches of unequal length produced along it. The side branches may branch or they may be simple pedicels.
Umbel: is an inflorescence having several branches arising from a common point at the summit of the peduncle. If these branches end in flowers, we have a simple umbel.; if they end in secondary umbellets, we have a compound umbel. The blooming sequence is generally from the outside in. The umbel may have a group or whorl of bracts, collectively called an involucre, at the summit of the peduncle. The main branches of a compound umbel are called rays, and the corresponding members of the umbellets are called pedicels.
Head: is a short condensed spike; also referred to as a capitulum.
Department of Botany, The Field Museum
Chicago, IL 60605-2496