The Geranium Family
 |
 |
| Pelargonium var. Avenir. spp. |
Geraniaceae sylvaticumspp. |
The Geraniaceae are widely distributed, found in both temperate and subtropical regions. They are not commonly found in the tropics.
If they are it is generally at high altitudes. There are 14 genera and 775 species in the Geraniaceae family.
The three major genera include; Geranium with 300-400 species, Pelargonium with 250-280 species and Erodium with 60-90 species.
They are annual or perennial herbs or shrubs that are often times aromatic.
Click here for a distribution map of the Geraniaceae in the U.S.A.
Vegetative Characters | Reproductive Characters |
Diagnostic Characters | Economic Importance/Fun Facts
| Evolutionary Adaptations and Relationships | Glossary of Terms |
References and Links | Pictures
- pubescence glandular, with ethereal oils
- stems are jointed at the nodes
- leaves can be palmately or pinnately compound or simple with lobes
- usually 5 petals and 5 sepals
- inflorescence determinate
- generally shrubby plants
- flowers are usually actinomorphic and perfect
- leaves alternate or opposite
- often have rhizomes
Back to top
- androecium usually has 10 stamens that are arranged in 2 whorls
- sometimes there are stamen and stamenoids
- gynoecium consists of one pistil that usually has 5 carpels
- ovary is superior
- the fruit is a schizocarp with 5 segments
- schizocarps in many Geranium species are explosive
- endosperm reduced or not present
- pollinated by insects
- in the Geranium family seeds are kept in closed segments containing
hygroscopic awns. The awn uncoils in response to moisture and drives the fruit section
into the ground.
- style persists in the fruit, appears as a beak
- plants are synoecious
- most are protandrous some self pollinate
Back to top
- many are highly aromatic
- five carpelate gynoecium
- long pointed beak that forms from the style
- five petals and sepals with 10 stamen
Back to top
- oils are used in perfumes
- cultivated as ornamentals
- many Geranium are native to North America
- Erodium cicutarium is a weedy annual that is edible for cattle when young but the dried mericarp
can cause livestock injury
Back to top
- most of the species are members of the monophyletic tribe Geraniaea that is characterized
by two ovules per carpel and an elastic schizocarp
- thought to be closely related to the Oxalidaceae
- may also be related to the Crossosomataceae and Stephyleaceae
- no morphological synapomorphies are known for the Geraniaceae
- Geraniaceae are monophyletic
- capsular fruits are a pleisomorphic feature
- bilateral flowers and a spurred sepal are considered autapomorphies for Pelargonium,
Erodium and Geranium
Back to top
- awn- a stiff bristle
- hygroscopic- change in form or size with change in moistures
- schizocarp- a fruit from a compound ovary that breaks into single carpelate unites that contains one or more seeds
- protandrous- anthers mature and shed polled prior to stigmas becoming receptive
Back to top
- Judd et al., 1999. Plant Systematics: a phylogenetic approach. Sinauer Associates, Inc. Sunderland, MA U.S.A.
- Walters, D.R. and D.J. Keil, 1996. Vasccular Plant Taxonomy, Fourth Edition. Kendall/Hunt Publishing Co. Dubuque, IA 52002
- Zomlefer, Wendy B., 1994. Guide to Flowering Plant Families. The University of North Carolina Press Chapel Hill, NC USA.
Back to top
 |
 |
| Carolina cranesbill Geranium carolinianum L |
beak structure from a geranium flower Geranium carolinianum L |
 |
 |
| Crane's Bill (Stork's Bill, Filaree), Erodium cicutariumspp. |
Geraniumspp. notice lobed leaves |
Back to top
For questions or feedback, contact:
Catharine Calandra