Lippia

• Summer-growing, broadleaved perennial herb with thick, woody taproot.
• Leaves are 1–3cm long, in pairs at stem nodes, have blunt serrated edge towards tip, taper to short stem.
• Stems and leaves are greyish-green.
• Flowers are small; tubular; white, cream, pinkish or pale lilac; 5–10mm in diameter.
• Fruits are rounded, 1–1.5mm in diameter, split when mature to release 2 flat, brown, oval seeds.

• Well-adapted to floodplain environments and prefers heavy clay soils.
• Readily establishes on bare ground and can take over large areas of land along waterways and adjacent higher ground.

• Well-established in Condamine and Border Rivers catchments in southern Queensland.
• Present in Burnett region and Maranoa-Balonne and Warrego-Paroo catchments.

• Flowers appear between spring and autumn.
• Tolerates drought and frost, can survive long periods of inundation.

Environmental

• Serious environmental and pastoral weed in Murray-Darling river system.
• Poses serious threat to protected wetland areas.
• Dense carpet-like spread prevents growth of other riparian vegetation.
• Resulting soil erosion decreases bank stability and degrades waterway health and quality.

Economic

• Aggressive weed that out-competes pasture species, reducing stocking rates by up to 90%.

• Spread by floodwater, seed dispersal, vehicles, machinery, birds and livestock.
• Spread appears to be related to flood events, with significant rainfall and flooding likely to result in population 'explosions'.

• Find out how farmers can prevent weed spread.
• Find out how gardeners and outdoor enthusiasts can prevent weed spread.

Mechanical control

• Short-term control can be achieved where infestations can be ploughed or harrowed. This method is not practical if lippia is growing in riparian zones (such as creekbanks) due to high risk of erosion and soil loss.
• Not usually a problem in cropping areas as can be readily ploughed into soil. However, machinery easily spreads lippia, so machinery working in infested areas should be washed down before leaving area.
• When lippia is actively growing and soil moisture levels are good, herbicide can be used in conjunction with mechanical control to give better results.

Herbicide control

• As lippia is a broadleaved weed that occurs in pasture situations, some herbicides can be used to reduce lippia without harming competitive grasses.
• Limited herbicides registered for use, but no currently available herbicide will effectively suppress growth in the long term. Due to lippia's ability to rapidly recover and spread, multiple herbicide applications within a season have been shown to give better suppression than single applications. However, herbicide control can become costly in areas with large infestations.
• Herbicide control is not suitable in riparian areas due to risk of polluting waterways. Also, herbicides should not be applied immediately after rain or if heavy rain is forecast.

Read the lippia fact sheet (PDF, 714KB) for herbicide control and application rates.

• Lippia is not a prohibited or restricted invasive plant under the Biosecurity Act 2014. However, by law, everyone has a general biosecurity obligation (GBO) to take reasonable and practical steps to minimise the risks associated with invasive plants under their control.
• Local governments must have a biosecurity plan that covers invasive plants in their area. This plan may include actions to be taken on Lippia. Some of these actions may be required under local laws. Contact your local government for more information.