Weeding out the invaders

The University of Queensland St Lucia campus is known for its lakes, sandstone and lush greenery, but invasive species are lurking among the foliage.

While the rosewood (Tipuana tipu) might be identified as an attractive ornamental tree, it is one of 28 species on the Department of Environment’s Alert List for Environmental Weeds that threaten biodiversity.

UQ Senior Grounds Supervisor Shane Biddle is determined to weed out the rosewoods and other pest plants, and to replace them with mature natives.

“In summer the rosewoods provide excellent shade but unfortunately, being an introduced species, they also bring problems,” Mr Biddle said.

“The tree has the ability to spread into open areas very quickly and disrupt natural ecosystems.”

The UQ Properties and Facilities division will replace rosewood trees on Walcott Street with mature 4-6 metre deep yellowwood (Rhodospheara rhodanthema).

The eastern Australian natives already feature on campus. Notably, yellowwoods were planted late last year as part of the Sir Fred Schonell entry upgrade.

“Due to the aggressive pruning to avoid the power lines, the rosewood’s we’re removing are lopsided which makes them a hazard in a storm,” Mr Biddle said.

“The new trees we’re planting will provide a good canopy without interfering dangerously with the power lines.”

Removing weeds and replanting native species is part of a larger year-long program at the St Lucia campus.

This year thousands of natives have been planted on the Brisbane River bank, along Sir William Macgregor Drive, to help prevent erosion and provide homes for native species.

“We’ve just dug another 500 holes and we’re looking for more volunteers to help us plant native trees.” Mr Biddle said.

For more information on volunteer tree planting, head to the UQ sustainability website.

Media: Casey Fung, c.fung@uq.edu.au, +617 3346 7887