CASSIA FISTULA: CHARACTERISTICS, TAXONOMY, HABITAT, DISTRIBUTION, USES - BIOLOGY - 2025

Cassia fistula is an ornamental tree belonging to the Fabaceae family. It is commonly known as caña fistula, cañafistula, carao, cañadonga, canafistola, cassia purgative, or golden shower.

It is a medium-sized tree around 15 m, gray stem, beautiful yellow flowers grouped in hanging clusters that adorn the environment where these trees are found.

Cassia fistula tree. Source: The original uploader was Peter1968 at English Wikipedia.

It is a species native to India but is cultivated in many tropical and subtropical countries. It grows in warm, dry environments, in well-drained soils, and is found in the wild in deciduous forests.

It has numerous medicinal uses such as antifungal, antioxidant, antimicrobial, anti-inflammatory, antitumor, hepatoprotective, hypoglycemic and others.

On the other hand, its pulverized seeds are useful for the coagulation of raw water during the treatment of water for human consumption.

characteristics

Appearance

It is a medium-sized tree up to 15 m tall and has no thorns. The crown of this tree is not leafy, on the contrary it is quite open and concise. It has a smooth bark, brown or gray in color, which darkens as time passes. The branches have lenticels, are devoid of pubescence, are ascending and finally hang down.

The Cassia fistula has hanging flower clusters from which it owes its name Golden Shower. Source: pixabay.com

Leaves

The leaves of this tree are alternate, paripinnate, 15-40 cm long, with a 10-30 cm rachis, no glands and a glabrous petiole up to 10 cm long.

The leaflets have a semicoriaceous texture, they are located from 3 to 8 opposite pairs. The shape is ovate or elliptical and measures 7 to 18 cm long by 4 to 8 cm wide, with a wavy or smooth edge, pointed apex and obtuse base.

The color of the leaflets is dark green with a shiny appearance on the upper surface, while the underside is somewhat opaque.

In addition, it has non-pubescent petioles that are between 3 and 10 mm long; also drooping stipules about 2 mm long, with trichomes.

flowers

The flowers are produced from spring to summer. They are supported by thin pedicels 6 cm in length. They form hanging, axillary, not very branched clusters that are 20 to 40 cm long, where each cluster bears 15 to 60 yellow flowers that measure 3 - 5 cm in diameter.

The flowers have a strong odor, open simultaneously, have linear or caudate bracts, deciduous and puberulent.

The calyx contains 5 yellowish-green sepals with some pinkish tones. The shape of the sepals is obovate-elliptical and they are 7 to 10 mm long.

Cassia fistula flowers. Source: pixabay.com

For its part, the corolla has 5 oval yellow or golden petals and they measure 30 to 35 mm long and 10 to 15 mm wide.

The androecium is made up of ten stamens of which three are longer than the others and whose filaments are curved, measuring 30 to 40 mm long. The anthers are 5 mm long and have both apical and basal clefts.

The gynoecium is formed by a stipitate, tomentose ovary, with a style that is approximately 4 mm long and ends in a small stigma.

Fruit

As in other fabaceae, the fruit of the Cassia fistula is a cylindrical legume that hangs from the branches, does not present pubescence and is indehiscent.

The pod is 20 to 60 cm long by 2 cm wide, round at the ends, dark brown or black at maturity.

The ripening of the fruit occurs slowly, it occurs from December to March and the fruits hang from the tree for a long time. Each legume can contain at least 40 seeds, and at most 100 seeds.

Immature legume and leaves of Cassia fistula. Source: Jim Conrad

Seeds

The seeds are obovoid or ellipsoidal, 7 to 10 mm long by 6 to 7 mm wide, smooth, reddish-brown, and surrounded by a mucilage of a sweet dark color and rubbery texture.

Taxonomy

-Kingdom: Plantae

-Filo: Tracheophyta

-Class: Magnoliopsida

-Subclass: Magnoliidae

-Superorden: Rosanae

-Order: Fabales

-Family: Fabaceae

-Gender: Cassia

-Species: Cassia fistula L. (1753)

Some synonyms for this species are: Bactyrilobium fistula, Cassia bonplandiana, Cassia excelsa, Cassia fistuloides, Cassia rhombifolia, Cathartocarpus excelsus, Cathartocarpus fistula, Cathartocarpus fistuloides, Cathartocarpus rhombifolius.

Habitat and distribution

Cassia fistula is a tree native to India, but it is grown in many tropical and subtropical countries.

Its distribution is in Angola, Argentina, Antigua and Barbuda, Australia, Belize, Barbados, Brazil, China, Colombia, Costa Rica, Cuba, Dominican Republic, Guatemala, El Salvador, Ethiopia, Grenada, Guyana, Haiti, Malaysia, Mexico, Nicaragua, Pakistan, India, Iraq, Iran, Panama, the Philippines, Tanzania, Thailand, the United States, Venezuela or Vietnam, among others.

In the wild, this tree is found growing in deciduous forests. It adapts to both hot and dry conditions and where frost does not occur, with temperatures of 18 to 30 ° C and well-drained soil.

Cassia fistula is a very ornamental species. Source: pixabay.com

Applications

Cassia fistula is used primarily for ornamental purposes in gardens or streets, and as shade trees around houses.

In recent research, the seed powder of this plant showed coagulant properties to purify or treat raw water, without the addition of chemicals. This is due to the set of proteins present in the golden shower.

As well, the coagulant produced by the pulverized seeds can diminish the turbidity and the color of the water treated for consumption.

The dose of the seed powder for effective coagulation is 20 parts per million. This dose does not affect the pH, alkalinity and hardness of the water for the 20 mg / L concentration of coagulant established in Colombia for drinking water, where the research was carried out.

In this sense, Cassia fistula can substitute inorganic coagulants harmful to health such as alum during the treatment of water for consumption.

Medicinal properties

This plant has shown to have medicinal effect or activity as an antifungal, antioxidant, antimicrobial, anti-inflammatory, antitumor, hepatoprotective, hypoglycemic.

In addition, its consumption is recommended for the treatment of jaundice, gout, fatty liver, bronchitis, and some skin diseases.

The pulp of the fruit is used as a mild laxative, to treat heart conditions, or for digestive problems such as acid reflux.

The flowers are used to lower fever, and its root as a diuretic.

The leaves and bark are used to treat skin conditions.

On the other hand, the seeds are antibiotic, appetizing, carminative and laxative.

References

1. Ajay, K., Satish, S., Ibrahhim, S., Karunakara, H. 2017. Therapeutic Uses of Cassia fistula: Review. International Journal of Pharma and Chemical research 3 (1): 38-42.
2. Sánchez de Lorenzo-Cáceres, JM 2015. Cassia fistula (Leguminosae-Caesalpinioideae) in Murcia ?. Taken from: arbolesornamentales.es
3. Catalog of Life: Annual Checklist 2019. Species details: Cassia fistula L. Taken from: catalogueoflife.org
4. Tropics. 2019. Cassia fistula L. Taken from: tropicos.org
5. Guzman,. L., Taron, A., Núñez, A. 2015. Cassia fistula seed powder as a natural coagulant in the treatment of raw water. Biotechnology in the Agricultural and Agroindustrial Sector 13 (2): 123-129.