Cockspur coral tree

Erythrina crista-galli is a small tree, the girth of its trunk measuring 50 cm (20 in). Normally it grows 5–8 m (16–26 ft) tall, although some individuals, such as in the Argentine provinces of Salta, Jujuy and Tucumán, can grow up to 10 m (33 ft). The woody trunk of the tree is equipped with irregular and thorny branches and can reach 50 cm in circumference. The root is a taproot with nodules produced by nitrogen-fixing bacteria. The bacteria live in symbiosis with the tree, facilitating the tree's absorption of nitrogen in return for organic substances which the bacteria need. The tree's trunk is woody with irregular, spiny branches. These branches form a layer without definite form and die after flowering.

Flowers and fruit. The red flower, arranged in inflorescences of the raceme type, is pentameric, complete, and of bilateral symmetry. Its calyx is gamosepalous, like a little red thimble. The corolla, like that of other legumes like common beans, is butterfly-shaped; however, the largest petal, called the "standard", is arranged in the lower part. The two petals called "wings" are so small that they are practically hidden within the calyx. The remaining two petals partially fuse together on occasion and form the flower's keel or "carina"; this protects its reproductive organs. …

It is distributed throughout northeastern and central western Argentina, eastern Bolivia, southern Brazil, much of Paraguay, and almost all of Uruguay. It lives in low, flood-prone places, and along the watercourses of the Chaco and the Eastern Region. It does not inhabit high forests or dry places without floods, as it tolerates water-saturated soils very well. This species characteristically grows wild in gallery forest ecosystems along watercourses, as well as in swamps and wetlands. It is naturalised in parts of Australia where it is a declared weed in some areas.

It has dyeing and medicinal applications: its bark is used to treat rheumatism wounds and serves as a diuretic antispasmodic; its resin can cure intestinal diseases; Its leaves contain camphor, that helps wound healing and has anti-inflammatory properties for tumors.

In cultivation in the United Kingdom this plant has gained the Royal Horticultural Society's Award of Garden Merit. In urban settings, it is often planted in parks for its bright red flowers.