Invasive weed control authority Castlereagh Macquarie County Council (CMCC) is advising landowners across the region to be on the lookout as a new invasive species crawls south into NSW.

The toxic Sticky Florestina competes with native grasses and is harmful to grazing animals as all parts of the plant are toxic and unpalatable.

Andrea Fletcher-Dawson, Senior Biosecurity Weeds Officer from CMCC said sheep travelling from central Queensland have spread it through central NSW.

"We're really on the alert because it's a new weed coming in from Queensland that has not yet had the opportunity to establish in NSW due to our early detection procedures," said Ms Fletcher-Dawson.

"A lot of people won't know what to look for, so my message is, if you spot anything that's growing that you haven't seen before, just ring Castlereagh Macquarie or your local control authority to get it identified."

Sticky Florestina grows about one metre tall, is covered in short sticky white hairs and has numerous flower heads with small white-coloured flowers, sometimes pink purplish.

The plant produces sticky seeds which can easily be distributed on vehicles, livestock and native animals.

Armidale Regional Council announced on 12 August that the weed may have entered its area, while Narrabri Shire believes the weed has also appeared there.

The weed was first detected in our area in 2021 by a Gilgandra landowner, Ms Fletcher-Dawson said.

The plant is native to southern Texas and Mexico, and was accidentally introduced to Australia via contaminated pasture grass seed in the mid-1960s, according to the Queensland government.

Ms Fletcher-Dawson said recent rainfall has provided fertile ground for the weed, which can flower throughout the year.

"So, we're all about jumping on early detection and awareness. That's our daily mantra."

She said that Hudson pear and Green Cestrum - both harmful weeds which have been present in the wsetern plains for several years - will also have the chance to spread.

Green Cestrum is poisonous to people, pets, livestock and native animals, and is spread by birds.

"There have been many reports of cattle deaths from Green Cestrum, and I urge anyone with stock to regularly check their paddocks especially under trees and fence lines," she said.

In mid-August, she said three Hudson pear cactus plants were found along a road in the Warrumbungle shire about 17 kilometres from a contained infestation at Quanda in the Coonamble Shire.

County Council Chairman Doug Batten said he strongly urged all residents of the region to be on the lookout and suggested residents familiarise themselves by using the Local Land Services website to help with identification of invasive weeds for their region.

Sticky Florestina flowers. Sticky Florestina seedlings.[IMAGE: DAF Qld]

"All managers of land have an obligation to control invasive weeds on their land, and it’s best to know what weeds you are dealing with in your area, so you can act quickly to ensure problem weeds are dealt with in a timely manner to reduce their spread and long-term effects on the environment," Mr Batten said.

"I would encourage residents to contact CMCC Biosecurity Officers if they need help with weed identification, as its important for all stakeholders to work together to control and reduce the spread of invasive weeds."