A Decade of Hop Powdery Mildew in the Pacific Northwest

Fig. 6. Hop plants where basal growth has been removed by carfentrazone-ethyl (A) or left untreated (B, shown here). Removal of basal foliage with chemical desiccants effectively reduces inoculum of Podosphaera macularis, and is important for reducing later infection of leaves and cones. Achieving adequate cover of dense basal growth, as in B, during fungicide applications is difficult.



Image from Plant Health Progress article:
A Decade of Hop Powdery Mildew in the Pacific Northwest