Albizia julibrissin

author: Michael Shields
email: mshields@arches.uga.edu

Common Names: Acacia (Small 1933), Mimosa, Silk Tree (Isely 1990)

photo Michael Shields

Classification
Family: Fabaceae
Subfamily: Mimosoideae
Tribe: Ingeae
Genus: Albizia
Species: julibrissin

Identification
Here is how Small describes the species: "Shrub or tree becoming 10 m tall: leaves with 16-24 pinnae; leaflets 5-7, the blades falcate lanceolate, 7-16mm long, obliquely acute: calyx about 2mm long: seed elliptic, 3.5-4.5 mm wide. The spikes of the flowers are pink" (Small, 1933.). Isely goes on to describe the flowers and legumes: "in pink or rosy umbels 2.5-5cm in diameter; pedicels less than 1mm long, glabrate. Legume 15-20cm x 1.5-2.5cm." (Isely 1990). The genus and species were both originally described by Durazzini.

Geography
Albizia julibrissin is native to Asia, and introduced to the US. It grows throughout the Southeast from Florida to Lousiana, Kentucky and Maryland.
It is frequently found in Georgia and in Clarke County.

Albizia julibrissin

AREA STATUS REFERENCES
North America:
Continental United States; Canada
Yes Isely, 1990
Eastern North America:
United States east of Mississippi;
Ontario and eastern Canada
YesIsely, 1990
Southeastern United States:
AL AR DE DC FL GA KY MD NC SC TN VA WV
Yes, not WVIsely, 1990
Southern Appalachian States:
AL GA KY MD NC SC TN VA WV
Yes, not WVIsely, 1990
Coastal PlainYes(map book)
PiedmontWidespreadMichael Shields, pers. obs.
Blue Ridge MountainsYes(map book)
Great Smoky Mountains National Park
YesMichael Shields, pers. obs.
Ridge and ValleyYes(map book)
Cumberland PlateauYes(map book)
Central Arch?
GeorgiaFrequentMichael Shields, pers. obs.
Clarke County, GeorgiaWidespreadMichael Shields, pers. obs.
Sams Farm?
Old Field
?
Wetland
?
Woods
?
1-Hectare Plot
?
photo Michael Shields

Natural History
Albizia julibrissin grows the best in full sunlight, although it also tolerates partial shade. It is a very hardy plant, and will grow in a wide range of soil types, including sandy, well-drained, wet, alkaline, drought dried, clay, and can also tolerate acidic soil Floridata). The tree flowers in the spring and early summer. It is deciduous, but since it often grows in tropical and sub-tropical climates, often keeps its leaves year round (Small 1933). It was originally brought over to the US to be cultivated as an ornimental, but quickly naturalized. It is even considered a weed in some locales (Destefano 1998, , Gardenweb)

How to Encounter
Mimosa trees are easy to find, because they often grow right along roadsides as well as open pine forests and hummocks. They are often cultivated as ornimentals for lawns (Small 1933). They are easily recognizable because of their fern-like leaves, and especially by their pink flowers in the spring and summer (see images). I often find them bith on small neighborhood roads and along interstates. Near the UGA campus the access ramp to GA Hwy 316 W off College Station Rd. Is dominated by mimosa trees. Stands like this fill a warm summer night with their sweet scent. Make sure to stop and notice this if you cycle or drive with windows open.