Loose smut is recognizable as soon as the affected heads emerge from the boot.
Usually the entire head will be diseased. Infected seed does not show any outward symptoms, and seed germination is not affected. To be effective, the control method must kill the fungus inside the seed without injuring the germ. The only seed protectant materials effective against loose smut are those with systemic activity. Certified seed should be relatively free of loose smut infections.