Department of Primary Industry and Fisheries Central Queensland cotton extension officer, Susan Maas, said spray drift prevention was an essential aspect of using agricultural chemicals responsibly.

Ms Maas, who works in cooperation with the Cotton Catchment Communities CRC and Research Development Corporation, said crop damage caused by spray drift of agricultural herbicide or pesticide was a significant concern for all growers and livestock producers.

"Herbicide spray drift damage to cotton has again been reported on the Central Highlands, Dawson Valley and on the Mackenzie River," Ms Maas said.

The 2008-09 predominantly irrigated cotton planting in Central Queensland amounts to 12,000 hectares on the Central Highlands and 4800ha in the Dawson-Callide.

Ms Maas said it was vital to communicate with neighbours and spray contractors to initially identify any sensitive crops in the area and then use well set-up, calibrated equipment to improve spray efficacy as well as minimise the risk of drift.

"The bulk of the damage has been attributed to phenoxy-type chemicals such as 2,4-D and Starane moving off target trapped in meteorological inversion layer air movements," Ms Maas said.

"Despite some excellent summer planting rains, some grain growers are opting to hold over fallow cultivation country to plant early winter wheat or chickpeas due to low sorghum grain market values.

"To control grass and broadleaf weed growth and to conserve soil moisture, growers should be selecting spray nozzles to apply coarse droplets that are too heavy to remain suspended in thermal air movement."