Powdery mildew of Strawberries

The disease is common in late summer.  The mildew survives as microscopic spores in tiny black spheres called cleistothecia.  In some areas cleistothecia are common.  In other areas their presence has not been confirmed.  Presence or absence of the cleistothecia is a critical factor in controlling the disease.  We need your help to confirm whether or not cleistothecia are found in your area.