Then a second paddock, also sown with oats, started to develop the same pattern.

Mr Wilson believes the crops have been poisoned, and he's called in the Environmental Protection Agency to conduct tests.

Without knowing what the paddocks have been sprayed with, he's too fearful to put his cattle on the oats and risk harm to them.

"I'm hoping its going to be only Round Up, but the way its burned in, who knows," Mr Wilson said.

A big zig zag, easily a metre wide, of dead crop is easily visible in a 25 acre paddock stretching all the way along a hillside.

Cattle had already been turned in to graze another 35 acres of oats while Mr Wilson was in hospital, with the pattern only obvious after he arrived home and too late to stop them.

He is also awaiting tests on those cattle, to check they are ok.

"Why would anyone stoop so low, especially in these conditions, when farmers need as much feed as they can get," Mr Wilson said.

"You really have to be scraping the bottom of the barrel."

Mr Wilson said the EPA investigators had indicated to him that such poisoning could attract a fine of $125,000 and even a jail sentence.

Mr Wilson said he has been in contact with police, but without any proof as to who sprayed the crop, there is little they can do.

He is currently considering hiring an investigative team to take the matter further.