Farmers in southern and western NSW are facing a locust plague as the drought eases in parts of the state.

The NSW Government said hundreds of landholders around Wagga Wagga, Narranderah and Dubbo have reported locusts breeding on their properties in the last few weeks.

It is racing against time to identify and eliminate the locusts with aerial spraying over the next 10 days, before the insects form giant swarms, said Primary Industries Minister Ian Macdonald.

"A locust swarm is a fearsome thing and it does massive damage, and that would be the cruel irony of the situation with the drought easing," Mr Macdonald said. "We are urging farmers to get the message and get out there and check [their properties]."

The area of NSW officially in drought has declined slightly to 69.2 per cent, with 16.8 per cent classed as marginal and 14 per cent satisfactory, according to government figures released today. This time last year, about 78 per cent of the state was in drought. Coastal zones are faring better than the inland.

Crop production has leapt from 1.8 million tonnes in 2007 to 5.8 million this year, though it is still below "normal" levels of eight to 10 million tonnes.

Thanks to good September rains, the Hunter, Maitland, northern New England and Tamworth regions are now classified at satisfactory.

However, the regional divisions of South Coast, Wanaaring and Wilcannia have moved from marginal to drought.

Ben Cubby is the Herald's Environment Reporter