stevia

REDUCING INVASIVE WEEDS

HAVE YOU SEEN STEVIA (CANDY LEAF)?

JUNE 2024

The hunt is on for the invasive weed stevia in the Ravenshoe and Herberton region.

Stevia ovata, or candyleaf, is in flowering season so now (June) is the best time to identify it.

Terrain NRM is working with Tablelands Regional Council on a project to control this weed and to keep it from spreading any further in Australia than the Atherton Tablelands, the only place it has been found.

Flowering season – May-June – easiest time to identify stevia

Terrain’s Evizel Seymour said stevia, which has the potential to compromise grazing land and natural vegetation, is controllable if everyone works together.

“Research has shown the seed only lives for 18 months and is not as mobile as something like Siam weed,’’ she said. “It was first found in this region in 2007. The growing season is February to May with a flowering season from the end of May through June.

A controllable weed if everyone works together

“We know this is one of the weeds we can get on top of. The best time to control stevia is before it flowers but identifying it is the first step to controlling it.”

Terrain NRM secured funding through the Queensland Government’s Queensland Feral Pest Initiative to follow on from earlier stevia control work by partnering with Tablelands Regional Council to work with landholders and others including Ergon Energy, Powerlink, Clean Co and the Queensland Parks and Wildlife Service.

Control work, with herbicides, is reducing the size of outbreaks on private and public land.

“Getting to stevia before it flowers and sets seeds means there is no seed bank for the future,’’ Evizel said. “By July to August the top of the plant dies off naturally but the bottom can re-shoot with moisture and the problem continues unless it is being controlled.”

Stevia ovata (candy leaf) – Fast Facts

Native to tropical America, it was first found in Australia, on the Atherton Tablelands, in 2007. This is the only place it has been found in Australia. It’s a category 3 restricted invasive plant under the Queensland Government’s Biosecurity Act 2014.
Stevia can form dense stands of vegetation, can rapidly colonise open, disturbed habitats and has potential to replace native plants and pasture.
The plant is usually 50cm-100cm tall but it can grow up to 3m tall with some plants having over 30 stems and a large, strong rootball. It has white or light pink flowers in May-June. Its leaves
are arranged in mostly opposite pairs along the stem, but sometimes alternately.
It grows across a range of habitats on the Atherton Tablelands at the higher altitudes including open woodlands, native pastures and disturbed sites like roadsides and under powerlines.
Seeds can spread on the wind, in water, on machinery and animals.

If you think you have stevia ovata (candy leaf) on your property, or you have seen it in the region, or you want to know more about this invasive weed, contact Tablelands Regional Council at info@trc.qld.gov.au, by phoning 1300 362 242 or visiting the customer service centre.