See:
Fungicide Effectiveness as Seed Treatments for Cereal Diseases
Cause Ustilago segetum (= U. kolleri), a fungus carried on seed.
Symptoms Blackish masses of smut spores replace kernels. The smut mass tends to remain enclosed by a whitish membrane until broken by harvesting. Chaff is not completely destroyed as it is with loose smut of oats.
Cultural control Avoid using contaminated seed.
Chemical control Seed treatments.
- Apron (Group 4) alone is ineffective.
- Captan (Group M4) is registered but gives only fair control.
- Dividend Extreme (Group 3 + 4) at 2 to 4 fl oz/100 lb of oat seed. See label for reentry restrictions.
- Raxil PRO MD (Group 3 + 4) at 5 to 7.5 fl oz/100 lb seed. See label for restrictions and application directions.
- Vitavax (Group 7) at 2 fl oz/100 lb seed plus a dye. Do not graze livestock in treated areas for 6 weeks.