Inflorescence Types - Horticulturebc.info

Verticillaster: Florets occurring in false whorls at nodes on a elongate stalk usually with 

pedicels and leaf-like bracts. Members of the Lamiaceae only and may appear spike-like. 

Inflorescence Types © Kwantlen.ca/Horticulture

Cyme: the growing tip becomes a floret before more arise from axillary buds. May apprea 

corymb-like and sometimes head inflorescences are arranged in cymes. 


Raceme: elongated inflorescence with floret pedicels of about equal length that develop 

along a rachis. 


Panicle: a main axis supports several racemes so that the inflorescence appears branched. 

Term often applied to any highly branched, elongate, inflorescence whose flowering 

sequence is s unclear, even if cymose. 


Catkin: florets unisexual, apetalous, and tightly packed together on a rachis that 

usually droops downward (found only in some woody dicots, e.g. willow, birch, alder, oak). 


Spikelet: inflorescence consisting of an axis (rachilla), above two bracts (glumes) and one or 

more very small florets with perianths reduced paired bracts (the palea and lemma). 

Spikelets may be arranged in spikes, racemes, or panicles. Found in grasses and sedges. 


Spadix: racemose inflorescence consisting of many tiny florets on an enlarged fleshy axis 

which is usually partially enclosed by a large bract (the spathe). In the Araceae only. 


Spike: inflorescence elongate and raceme-like but with very short or no pedicels. 


Head (Asteraceae): florets small, closely packed, lack pedicels, and arise from a flattened 

axis that is surrounded or subtended by bracts to appear as a large flower. Head 

inflorescences are commonly arranged in cymes and may be small. 


Head: florets small, closely packed, lack pedicels, and arise from a flattened axis that is 

surrounded or subtended by bracts to appear as a large flower. Mainly in Asteraceae. 


Umbel: pedicels (and rays if a compound umbel) of about equal length all arising from the 

apex of the peduncle. Mainly occur in the Apiaceae. 


Corymb: florets are formed on lateral stalks of different length, the longest being at the 

base creating a flat-topped inflorescence. 


Cyathium: consists of a simple female floret (one pistil) in the center surrounded by many 

simple male florets (one stamen each) on bracts. F.Y.I. - Found only in the Euphorbiaceae. 


Use the 

Key to the Basic Inflorescence Types 

in your lab manual or lecture handouts 

to identify the following unknowns . 

Practice identifying inflorescence unknowns 


Unknown #1 


Unknown #2 


Unknown #3 


Unknown #4 


Unknown #5 


Unknown #6 


Unknown #7 


Unknown #8 


Unknown #9 


Unknown #10 


Unknown #11 


Answer Key 

1) Catkin 

2) Verticillaster 

3) Head 

4) Corymb 

5) Raceme 

6) Panicle 

7) Spikelet (arranged in a panicle) 

8) Cyme 

9) Spadix 

10) Spike 

11) Umbel

Inflorescence Types - Horticulturebc.info

Create successful ePaper yourself

Delete template?

Save as template?