The sight of low-flying planes spraying mists of pesticides and fungicides over Iowa’s farm crops has been more common than usual this summer. Iowa’s Secretary of Agriculture Bill Northey says there are a couple of reasons for the increase in crop-dusting.

First, Iowa farmers have been battling an infestation of soybean aphids this year. And Northey says farmers are being very protective of their corn crops because of high prices created by the demand for ethanol.

Northey says there’s strong export demand, as well. He says over two billion bushels of Iowa’s nearly 12 billion bushel crop is being exported.

With more crop-dusters, come more risks for accidents. Earlier this month, a plane crashed south of Vinton after clipping a power line. Also, an Arkansas company was ordered to stop flying in Iowa after a pilot doused field workers with chemicals in Marshall County.