Apple scab caused by the fungus Venturia inaequalis is economically the most destructive disease in apple production worldwide. Apple scab control requires multiple applications of fungicides during ...

BOULDER COUNTY – Gardeners who plant apple trees are hopeful souls, putting in saplings as they dream of future pies, sauce, and tarts. With each season of growth, we croon encouragement at the plant.

The fungal infection causes dark scabby lesions on the leaves and skin of the apple, which leaves the flavor unaffected, but does effectively make it unsalable. “It’s a huge issue,” says Peter Wagner, ...