Botanical Name: Excoecaria agallocha
Species: E. agallocha
Common Names: Genwa, Blind-your-eye mangrove, Blinding tree,Buta buta tree, Milky mangrove, Poisonfish tree, and river poison tree.
Habitat: Excoecaria agallocha grows in saline or brackish water in tropical mangrove forests, in a distribution bounded to the west by India, to the north by Bangladesh, to the south by Australia. Within Australia, it thrives from northern New South Wales along the northern coastline around to Western Australia.
Excoecaria agallocha is an evergreen, or briefly deciduous shrub or small tree growing 10 – 30 metres tall. The bole, which branches from low down, has stilt roots. Trees are either male or female (dioecious). Male flowers form drooping tassels, while female flowers appear as shorter spikes. Pollinators such as bees commonly visit the flowers. The fruit is a small dark capsule.
The plant is sometimes harvested from the wild for local use as a medicinal herb. It is also often cultivated as an ornamental.
A widespread and common species, though there are some localised threats and there has been an overall population decline caused by coastal development throughout its range. The plant is classified as ‘Least Concern’ in the IUCN Red List of Threatened Species.
A plant of the lowland tropics and subtropics, where it is found at elevations up to 400 metres. It grows best in areas where annual daytime temperatures are within the range 20 – 30°c, but can tolerate 15 – 37°c. It prefers a mean annual rainfall in the range 1,000 – 2,000mm, but tolerates 800 – 4,100mm.
Requires a sunny position. Succeeds in a wide range of fertile soils. Tolerant of saline soils. Prefers a pH in the range 6.5 – 7, tolerating 6 – 8.
A dioecious species, both male and female forms need to be grown if fruit and seed are required.
Propagation: Through seeds.
Edible Uses: Not Known.
The latex is used as a caustic for removing obstinate ulcers. The latex is rubbed around the tip of the penis and left for three days. Although this causes irritation, it is also believed to enlarge the penis.
The juice is emetic and purgative. Very small amounts are taken orally with coconut juice to treat pneumonia or asthma. It may also be taken to clear out the body as a poison antidote.
The resin is used as an anthelmintic, for its purgative effect.
Oil extracted by distillation of the wood or latex is applied to cutaneous diseases.
Chewing a little piece of bark will cause instant vomiting and purging, but is in general considered too drastic a cure for constipation.
The root is used as an abortifacient.
Applied externally, the root is pounded with ginger and used as an embrocation to reduce swellings on the hands and fee.
Certain parts of the wood are used for incense. The white wood is soft and spongy. The roots are sometimes used as floats.
All parts of the plant are poisonous.
The tree exudes a very acrid poisonous juice, particularly from the fresh cortex when cut, which raises blisters on the skin and is injurious to the eyes of wood-cutters, whence the name ‘blinding tree’.
The latex is used as a fish poison. The crushed leaves, when placed in the water, stupefy the fish and cause them to float to the surface.
Disclaimer : The information presented herein is intended for educational purposes only. Individual results may vary, and before using any supplement, it is always advisable to consult with your own health care provider.