A Brazilian beetle with an appetite for a certain invasive weed could help to control the plant that grows thick in Maui’s forests and outcompetes native species.
Syphraea uberabensis is a small beetle whose adults and larvae feed on cane tibouchina in the beetle’s native region of Brazil. The state Departments of Agriculture and Land and Natural Resources are proposing the beetle’s release on state lands — starting with Maui and Hawaii Island — as a form of biocontrol against the invasive tibouchina and other related weeds.
“For a nasty weed like tibouchina, what we’re trying to do is . . . basically create more balance between the target tibouchina and the environment,” said Darcy Oishi, biological control section chief for the DOA. “It’s basically creating another tool to slow the weed down and allow more active and aggressive control mechanisms.”
A draft environmental assessment for the release of the beetle was published Thursday in the Office of Environmental Quality Control’s “The Environmental Notice.”
Cane tibouchina, known as Tibouchina herbacea, is a noxious weed native to southern Brazil, Uruguay and Paraguay. Its young stems are angled and hairy, with pink and purple flowers, and bright yellow anthers. Each plant can produce hundreds of seed capsules that can in turn produce up to 700 seeds the size of a grain of sand. These tiny seeds are easily dispersed through the wind or by wild animals, humans, vehicles or water.