How to Manage Pests
Pests in Gardens and Landscapes
Stamen blight—Haplosphaeria deformans
Flowers infected with stamen blight are white and powdery. Infected flowers may appear larger than healthy
flowers as their stamens are flattened against the petals and sepals; the stamens of healthy flowers
are in a ring around the stigmas. Anthers become be discolored and swollen. Fruit tends to be small and
hard to pick.
Stamen blight, caused by the fungus Haplosphaeria deformans, can be spread by wind, rain, bees, or even
mechanical means. Use disease-free plants and remove any wild blackberries or raspberries from the area
as they can provide a source for the disease. The alternate-year fruiting system may also help to provide
control of this disease, reducing any source of inoculum.