Locust battle reaching its peak in South Australia

The battle in South Australia to contain the worst locust plague in 40 years is entering its most important phase, with Premier Mike Rann describing it as a major challenge.

Mr Rann said an aerial spraying program had so far engaged five aircraft flying more than 233 hours and striking 248 targets across the states mid north, Flinders Ranges, the Riverland and the mallee.

The government has deployed 140 people in addition to support personnel from Natural Resource Management (NRM) boards and local government.

Aerial spraying has so far covered nearly 270,000 hectares, while crews on the ground are also involved in the eradication.

"With South Australia expecting its best harvest since 2001, its vital that we do everything possible to ensure any locust threat to that bumper crop is minimised," Mr Rann said.

"We know its impossible to eradicate all locusts that have or will hatch in coming weeks, but with a concerted co-operative effort between the state government, NRM boards, landholders and councils we can significantly reduce potential damage from locusts and importantly reduce their ability to swarm."

Mr Rann said one of the five planes used in the aerial sorties was exclusively spraying the organic fungicide, Green Guard, in conservation parks and similar sensitive sites.