Botrytis is damaging because it extensively sporulates in strawberry flowers and can spread quickly, particularly under the warm, wet conditions common at bloom time. As the fruit matures, Botrytis develops into a noxious gray mold that renders berries inedible. Consumers won't buy moldy strawberries and grower profits disappear into the nearest compost bin. To fight Botrytis, growers usually apply one or two chemical fungicides at bloom time. Trichoderma can be applied as a spray, but coverage would be wasted because sprays cover leaves as well as flowers.
Bees are by far the most efficient and effective delivery system.
Bees achieve better control, using one-tenth of the amount that would have to be used in a sprayer. Joseph Kovach inspects a super of bees that deliver Trichoderma to strawberry fields to fight gray mold. Pollination by bees also increases yield. The inserts slip into a reusable, lightweight 'doorstop'. The only maintenance required on the part of the grower or the beekeeper is to change the insert when it is empty, which could be every five to seven days during bloom, depending on bee activity and the weather.