See:
Fungicide Effectiveness as Seed Treatments for Cereal Diseases
Cause A fungus, Ustilago avenae, carried on seed.
Symptoms Powdery, black spore masses replace kernels and chaff. Black, smutted heads are easily distinguished as soon as heads emerge from the boot. Spore masses soon disperse and may not be evident at harvest.
Cultural control Avoid using contaminated seed.
Chemical control Seed treatments.
- Apron (Group 4) or Captan (Group M4) alone are ineffective.
- Dividend Extreme (Group 3 + 4) at 2 to 4 fl oz/100 lb of oat seed. See label for reentry restrictions.
- Raxil MD (Group 3) at 5 to 6.5 fl oz/100 lb seed plus a dye. See label for reentry restrictions.
- Vitavax (Group 7) is registered but gives only fair control.