Phytolacca dioica (Ombu)
(Unranked): Core eudicots
Species: P. dioica
Binomial name: Phytolacca dioica
Synonym: Pircunia dioca
Common names: Ombu
Phytolacca dioica a massive deciduous tree native to Argentina, Brazil and Uruguay of South America. It has a short, thick bole and a massively branched rounded crown that spreads to a girth of 12 to 15 meters. The tree can attain a height of 12 to 18 meters. It is the only tree-like plant that lives on the Pampas because it does not need a lot of water to survive. Because of this water shortage plants are found grow widely spaced.
The Phytolacca dioica’s massive enlarged base may grow to 4 m in diameter, spreading above the ground so that the tree appears to be standing on a mound. This base and the trunk contain water storage tissue which can contain up to 80% of water. This is an excellent fire resistant adaptation for the intense grassland fires which are common in this region. Since is derived from herbaceous ancestors, its trunk consists of unusual secondary thickening rather than true wood. As a result it grows fast so its wood is soft and spongy and can be cut with a knife. Since the sap is poisonous, the Phytolacca dioica is not grazed by cattle and is immune to locusts and other pests. The leaves are sometimes used as a laxative.
The bush is covered with dark, glossy, green leaves up 15 cm in length. The leaves occur alternately on different sides of the branchlets and have long pinkish petioles. The trees bark is rough, grey to pale brown and becomes gnarled with age.
Small creamy green white flowers are borne on terminal pendulous sprays up to 15cm long. The flowers have many stamens arising from 5 green sepals. They are unisexual and male and female flowers are borne on separate trees. After flowering yellow to black berries develop which hang in clusters.
Click here to see a photo of the flowers. Image at Plantsystematics.org Copyright © 2006 by M. Bonifacino
This is a report of the special tree photographed below. Report is from New Zealand's Register of Notable Trees: http://register.notabletrees.org.nz/tree/view/144
Photo of a Phytolacca dioica. It is the large tree (20 metres tall, 25-metre spread) in the middle of the photo. Photo taken on the corner of Leach and Hobson streets New Plymouth. It one of New Zealand's ten most notable trees.