Chilean rhubarb

Description

Gunnera tinctoria, known as giant rhubarb or Chilean rhubarb, is a flowering plant species native to southern Chile and neighbouring zones in Argentina. It is unrelated to rhubarb, as the two plants belong into different orders, but looks similar from a distance and has similar culinary uses. It is a large-leaved perennial plant that grows to more than two metres tall. It has been introduced to many parts of the world as an ornamental plant and in some countries (for instance New Zealand, Great Britain and Ireland) it has spread from gardens and is becoming a weed problem. It is known under the synonyms: Gunnera chilensis Lam. and Gunnera scabra Ruiz & Pav. It was first described in 1782 by Juan Ignacio Molina as Panke tinctoria, and was transferred to the genus, Gunnera, in 1805 by Charles-François Brisseau de Mirbel. Gunnera tinctoria is a giant, clump-forming herbaceous perennial. The leaves can grow up to 2.5m across, cordate and palmate with up to 9-lobed margins.It has erect spikes of cone-shaped inflorescences (to 1m) from spring to early summer, with small flowers. The fruit is orange. The number of seeds is estimated from 80,000 per seedhead to 250,000 per plant. In its native Chile, where it is called nalca or pangue, it is used in a similar way to European rhubarb: the stalks are eaten fresh or cooked into jam or cordial. The leaves are used in the preparation of the traditional Chilean dish curanto. n parts of New Zealand the Chilean rhubarb has become a recognised pest plant. For instance in Taranaki, on the west coast of the North Island it was spread to riverbeds, coastal cliffs and forest margins. G. tinctoria is on the National Pest Plant Accord. Under Section 52 and 53 of the Biosecurity Act, it is an offence to knowingly propagate, distribute, spread, sell, offer for sale. In Great Britain it has become well-established and sometimes problematic in western districts and appears to be spreading. In the west of Ireland, G. tinctoria is a major invasive species, in particular on Achill Island and on Corraun Peninsula, County Mayo. Its large leaves create dense shade, preventing other species from germinating or growing.