Lantana is listed as a weed of national significance and currently infested some four million hectares of Queensland and NSW grazing lands.

"Lantana costs the grazing industry an estimated $104 million annually in lost productivity and control costs and has an invasive potential to cover 35 million hectares," Minister for Primary Industries, Tim Mulherin, said.

"There are graziers in the Mackay region who are literally confronted with a wall of lantana on their holdings and are at a point where they are keen to develop management plans to progress recommended control options.

"More than 200 people have attended a series of four lantana control field days held in the Mirani, Eungella, Proserpine and Sarina districts since December to watch demonstrations of cost-effective mechanical and chemical control measures."

Biosecurity Queensland officers, Corey Bell and Caroline Sandral, Mackay, hosted two field days in late April in the Sarina and Proserpine districts in conjunction with Mackay and Whitsunday Regional Councils, Sarina and Whitsunday Landcare Catchment Associations and Mackay Regional Pest Management Group.

Ms Sandral said there was no doubt the gas-operated splatter gun was a clear winner at the field day demonstrations and regarded as an effective way of applying selective herbicides.

The splatter gun delivered a 1:9 glyphosate and water concentrate mix in each 15-20ml squirt in a well-directed large droplet splatter.

"The main advantage is that the gun can squirt the concentrate six to 10 metres to a specific target which reduces chemical usage and the potential for off-target environmental damage," Mr Sandral said.

The field day team also demonstrated the use of foliar spray units and basal bark and cut stump herbicide treatments. Participants had the opportunity to inspect pre-treated areas to compare the efficacy of each operation.