Corn Cane White Fluffy Dust: Pollen, Mites, Scale, or Mildew?

12-year corn cane, 2 new canes added. One flowered (fragrant, sappy). White fluffy "dust" spread during flower drying. Mites?

Possibilities

• Pollen from dried flower — wash off test
• Spider mites — webbing, leaves dry up
• Cottony scale — leaves brown
• Powdery mildew — rare on canes

Test

• Wash off first
• If insects: Safer's Insecticidal Soap 3–4 days × 3