Pasture burning benefits controlled grass growth and reduces woody plant species, but it also controls parasites. A 2012 study conducted in Iowa and Oklahoma examined the impact of patch burning on horn fly populations.

“By patch burning alone we were able to reduce the horn fly population without any insecticides,” says Justin Talley, entomologist with Oklahoma State University, who took part in the research.

A 41% reduction in horn flies was observed in patch-burned pastures versus non-burned pastures.

“We kept the fly levels down to a manageable level of around 200 flies per animal,” Talley says.

During peak fly season, cattle on non-burned pastures had more than 300 flies per animal, which is above the threshold for economic losses.

In the patch burning situation manure pats were being distributed in different areas helping to move around the fly populations. Also, the heat of the fire burnt the manure present in the pasture that would otherwise be a host for horn fly pupa.