Members of the mustard family often have their flowers in bractless racemes. (That’s so very un-animal-like! Are your feet older than your head?) The most typical plant inflorescences are thus indeterminate, and sometimes called “racemose,” after the most representative type, the RACEME. These regions of cell division are called “apical mersitems.” Thus, a typical plant stem that is producing flowers as it elongates will have: (a) no precisely set, predetermined number of flowers, i.e., it is of “indeterminate” length and flower number and (b) the lower portions are actually older than the upper portions. Plants grow by adding cells at their tips. (raceme, panicle, spike, catkin/ament, spikelet, spathe & spadix) ELONGATE DETERMINATE (RACEMOSE) INFLORESCENCES Pale white violet is a “stemless,” having a SCAPOSE inflorescence. The so-called “stemless” violets exemplify the solitary scapose inflorescence type. Scapes may either one-flowered, or few-several flowered. Sessile trillium flowers are non-stalked (sessile), solitary, and terminal.įlowers may be placed singly in the axils of normal foliage leaves, as in this Gattlinger’s false-foxglove ( Agalinus gattlingeri, family Orobanchaceae).įalse foxglove flowers are SOLITARY in the leaf AXILS.Ī SCAPE is a bare flowering stem arising from a cluster of leaves at the base of the plant. “Sessile” is term that, in botany, means “stalkless,” i.e., lacking an evident pedicel in the case of flowers (or lacking a petiole if it’s a leaf that’s being described). Large-flowered trillium solitary, stalked terminal inflorescence.Ī contrast that illustrates well another condition with respect to flower stalks is provided by another trillium, the aptly named “sessile trillium,” Trillium sessile. Note also in this species that the flower is stalked, i.e., having a pedicel (which in thus case is also a peduncle). grandiflorum) proudly displaying its TERMINAL SOLITARY inflorescence. Solitary inflorescences can be terminal, as in the genus Trillium. Some inflorescences are one-flowered, in which case the pedicel may (oddly, it seems) also be regarded to be a peduncle. Often, there will be a small leaf-like BRACT subtending a pedicel. A PEDUNCLE is the stalk of an entire inflorescence.

First, some basic terminology.Ī PEDICEL is the stalk of an individual flower. Moreover, some inflorescences are associated with particular plant families, for example: umbels in the carrot family (sometimes thus called the “Umbelliferae”) spikelets in the grass and sedge families, and a spathe/spadix combination in the arum family. The manner in which flowers are arranged on plants varies tremendously, and is often a key feature used to identify plants.

Cyme or panicle