jacaranda

Jacarandas
Flowering Jacaranda
Scientific classification
Kingdom: Plantae (unranked): Angiosperms (unranked): Eudicots (unranked): Asterids Order: Lamiales Family: Bignoniaceae Genus: Jacaranda Juss.
Species
See text.

Jacaranda (pronounced /ˌdʒækəˈrændə/; Portuguese: [ʒakəɾãˈdə], Spanish: [hakaˈɾanda]) is a genus of 49 species of flowering plants in the family Bignoniaceae, native to tropical and subtropical regions of South and Central America, Mexico, and the Caribbean. The genus name is also used as the common name.

Symbol

In many parts of the world, such as Mexico and Zimbabwe and Los Angeles, the blooming of this tree is welcomed as a sign of spring.

Brisbane, Australia adopted the Jacaranda over 150 years ago as there are very few flowering trees and plants which could survive the typical long dry winter. Many locals believe it is native to the region.

Growth

The species are shrubs to large trees ranging in size from 2 to 30 m tall. The leaves are bipinnate in most species, pinnate or simple in a few species. The flowers are produced in conspicuous large panicles, each flower with a five-lobed blue to purple-blue corolla; a few species have white flowers. The fruit is an oblong to oval flattened capsule containing numerous slender seeds. The genus differs from other genera in the Bignoniaceae in having a staminode that is longer than the stamens, tricolpate pollen, and a chromosome number of 18.

Large Jacaranda in full bloom.

Genus

The genus is divided into two sections, sect. Jacaranda (syn. sect. Monolobos, an invalid name as it includes the type species of the genus, J. caerulea) and sect. Dilobos DC., based on the number of thecae on the anthers. Sect. Jacaranda (which includes Blue Jacarandas) has 18 species and is found primarily in western South America, Central America, Mexico, and the Caribbean. Sect. Dilobos, which is believed to be the primitive form, has 31 species and is found primarily in southeastern Brazil including the Paraná River valley. The anatomy of the wood in the two sections also differs. Although usually treated in sect. Jacaranda, J. copaia differs somewhat from all other members of the genus, and may be intermediate between the two sections (Dos Santos & Miller 1997).

Selected species

Cultivation and uses

Jacaranda seedling

Several species are widely grown as ornamental plants throughout the subtropical regions of the world, valued for their intense flower displays. The most often seen is the Blue Jacaranda Jacaranda mimosifolia (syn. J. acutifolia hort. non Bonpl.). Other members of the genus are also commercially important; for example the Copaia (Jacaranda copaia) is important for its timber because of its exceptionally long bole.

Jacaranda in full bloom on 12th Main, Indira Nagar, Bangalore, India

Pretoria in South Africa is popularly known as The Jacaranda City due to the enormous number of Jacaranda trees planted as street trees and in parks and gardens. In flowering time the city appears blue/purple in colour when seen from the nearby hills because of all the Jacaranda trees. The time of year the Jacarandas bloom in Pretoria coincides with the year-end exams at the University of Pretoria and legend has it that if a flower from the Jacaranda tree drops on your head, you will pass all your exams. Other towns and cities in South Africa have Jacaranda trees, but none produce such a show as that of Pretoria.

The city of Brisbane, Australia has a local reputation of having a significant population of Jacaranda trees. The University of Queensland in the city's inner west has a very high concentration of the tree, and due to the impressive display of purple flowers in mid-Spring, which wind up littering vast sections of the suburbs, local folklore claims that "one won't start studying for exams until the jacarandas have molted". At Sydney University there exists a similar expression "by the time the jacaranda in the main quadrangle flowers, it's too late to start studying for exams".

This has led to the slang name "exam tree" or "purple panic" being attached to the plant. At the University of Queensland students even maintain a joke superstition that if a Jacaranda bloom falls on their head during exam time, they will fail an exam. The bad luck can be broken by catching another bloom before it hits the ground.

The reason for the Jacaranda's proliferation in Brisbane is often attributed to the thirties and forties, when new mothers leaving the maternity hospital were given a jacaranda sapling to plant.

Jacarandas in bloom have become closely associated with Brisbane and South East Queensland. The Brisbane City Council have used jacarandas to line avenues, and commercial developments in some areas, particularly along the Brisbane River have incorporated jacarandas into their landscape design. The trees are common in parks throughout the city, most notably in a long curved avenue in New Farm Park, in Goodna, and in private gardens. Brisbane's hilly geography allows views of the city and suburbs in which the brightly coloured flowers can be easily seen for miles. The jacaranda has become so much a part of the city's identity that contemporary art, particularly of streetscapes, often incorporates the flowering jacaranda, despite the fact that it only flowers for approximately six weeks from September through October.

Old church surrounded by jacarandas in bloom, Wooroolin, Australia.

The city of Grafton on the north coast of New South Wales, Australia, is also famous for its Jacarandas. Every October the city has a Jacaranda festival during the period of full bloom. A street parade, local public holiday and a series of events are held. A local public holiday sees the city's businesses perform street theatre for passers by and street stalls proliferate. A Jacaranda Queen and Jacaranda Princess are named at a formal ball.

Many of Sydney's north shore and harbour suburbs in the east have a dominate purple glow during late spring.

Jacarandas are also popular in the southern and central parts of Florida and the southwestern United States, notably in Phoenix, Arizona and San Diego, California. Jacaranda can be found throughout most of Southern California, where they were imported by the horticulturalist Kate Sessions. In California, jacarandas are known as the trees that bloom twice a year, although the fall bloom is generally not as striking as the spring bloom. Tampa, St. Petersburg, and other southern Florida cities are ribboned by purple flowers during peak bloom of April. Jacaranda trees are principally found in parks and interspersed along the avenues and streets. Jacarandas were introduced to Israel over 50 years ago, where they are in full bloom during May. They are popular and can be found in cities all over Israel.

Brazilian Jacaranda is also used as the wood for the body of acoustic guitars.

Gallery

Santiago de Querétaro in Mexico, with Jacaranda trees all over town.	Brisbane, Australia is noted for its jacarandas which are common in public areas, parks and suburban backyards.	Jacaranda trees in Montagu Ave, Harare, Zimbabwe in 1975.	Purple jacaranda flowers carpet the ground as they fall.
Jacaranda trees in Bhutan	Jacaranda in Mountain View, California, USA	Jacaranda in Auckland, New Zealand	Jacaranda mimosifolia

References

Notes

Bibliography

External links

• Germplasm Resources Information Network: Jacaranda
• Dos Santos, G., & Miller, R. B. (1997). Wood anatomy of Jacaranda (Bignoniaceae): Systematic relationships in sections Monolobos and Dilobos as suggested by twig and stem rays. IAWA Journal 18: 369-383. Available online (pdf file).
• Goodna RSL Jacaranda Festival at Evan Marginson Park, Goodna