Northern Ontario Plant Database
- Spike -
an elongate, unbranched, indeterminate inflorescence with sessile flowers.
- Spikelet -
a small spike, characteristic of grasses and sedges.
- Raceme -
an elongate, unbranched, indeterminate inflorescence with pedicelled flowers.
- Panicle -
a branched raceme.
- Corymb -
a flat-topped raceme with elongate pedicels reaching the same level.
- Compound Corymb -
a branched corymb.
- Umbel -
a flat-topped or rounded inflorescence with the pedicels originating from a common point. Umbels can be determinate or indeterminate.
- Compound Umbel -
a branched umbel, with primary rays arising from a common point, and secondary umbels arising from the tip of the primary rays.
- Capitulum (or head) -
a dense vertically compressed inflorescence with sessile flowers on a receptacle and subtended by an involucre of phyllaries, characteristic of the Asteraceae. Heads can be determinate or indeterminate.
- Thyrse -
a many-flowered inflorescence with an indeterminate central axis and many opposite, lateral dichasia; a mixed inflorescence, with determinate and indeterminate shoots.
- Simple Cyme or Dichasium -
a determinate inflorescence with 2 dichotomous lateral branches and pedicles of equal length.
- Compound Dichasium -
a branched dichasium
- Compound Cyme -
a determinate thyrse.
- Helicoid Cyme(or bostryx) -
a determinate cyme in which the branches develop only on 1 side, due to the abortion of opposing paired bud, the inflorescence thus appearing simple.
- Cincinnus -
a tight, modified helicoid cyme in which the pedicels are very short.
- Scorpioid Cyme(or rhipidium) -
a zig-zag determinate cyme with branches developing alternately on opposite sides of the rachis, due to abortion of opposing paired bud.