Summary: Lawrence Price, Northern Grower Alliance Timing foliar sprays to defeat aphids before too much damage is done to a crop is the key to the cost effectiveness of a post emergent chemical response to the pest. But getting the timing right is not easy. Often by the time aphids are noticed in a paddock damage has been done and predator insects are already building sufficient numbers to control the aphids making a foliar spray unnecessary and uneconomical. Early detection therefore...
