The tree that bleeds... metal?
Friday, September 14, 2018
Posted by: Dana Walker
Heavy metals like nickel and zinc are usually the last thing that plants want to grow next to
in high concentrations.
But a specialised group, known as hyperaccumulators, have evolved to take up the normally toxic metals into their stems, leaves and even seeds.
Researchers have been studying Pycnandra acuminata in particular - a tree that grows on the island of New Caledonia in the south Pacific.
They think it may use the nickel to defend against insects.
Its latex has an unusual blue-green colour as it contains up to 25% nickel.
"Pycnandra acuminata is a large (up to 20m tall) rare rainforest tree, restricted to remaining patches of rainforest in New Caledonia," says Dr Antony van der Ent, a researcher at the University of Queensland who has been studying the tree.