Keep an eye out for alligator weed

South East Local Land Services regional weeds coordinator, Alicia Kaylock, said the incursions had been spotted mainly in the coastal areas and thought to be associated with machinery.

"Alligator weed spreads from plant fragments, so stem and root fragments. So if you get a little piece of it it will grow a whole new plant from that," she said.

"When earth moving machinery and mowing machinery is used in an area where there's alligator weed and then taken somewhere else without being cleaned properly, you can end up with new infestations of alligator weed.

"That's what has been the biggest vector of spread for us in the south east."

A small, low growing perennial soft plant, Ms Kaylock said there was three main identifying features of alligator weed.

"It's got shiny spear shaped leaves that occur in alternate pairs, small white paper flowers and its stems are hollow," she said.

"That combination is a really good indicator that you have got alligator weed."

Ms Kaylock said the weed can cause a variety of issues for producers including blocking irrigation channels, contaminating turf making it unsaleable, and blocking stock access to water.

"If you had a dam full of alligator weed the cows are going to find it very hard to get a drink," she said.

"If you get in a water storage system it can damage those pumps and other water infrastructure. If it go into our water supply systems that would be a huge, huge problem."

Ms Kaylock said the first thing producers need to do if they see the weed was to contact their local council biosecurity officer and for south east producers this was a legal requirement as the area fell into an alligator weed biosecurity zone.

"Your local council can help you make a plan to control it," she said.

"The most appropriate control measures will depend on how old the infestation is, if it is really new it is much easier to get rid of, then if it's been established for a while, the size of the infestation, and the situation that it's growing in.

"If it's in flowing water versus an area of turf there's going to be different methods that are appropriate so it's really important to get expert advice on it."

Ms Kaylock said the worst thing to do was to slash or mow the weed.

"That will just make the problem worse," she said.

"Because it grows from those little plant fragments, if you mow it you end up with thousands more plants so it is a really critical thing not to do."

Ms Kaylock said overall it was important for landholders to keep an eye out for the weed, particularly if they have had machinery come onto their property, or had dams cleaned out.

"If something new pops up really important contact council and get advice if they're concerned," she said.

"That is what their weeds officers are there for to help."