Pre-Delivery Pear-baiting for Phytophthora

Story and photos by Maddie Ginn.

At Central Coast Wilds nursery, we participate in the CalPhytos Best Management Practices (BMP) program. A critical step in our production pipeline is pre-delivery pear-bait testing for Phytophthora, a devastating group of water mold pathogens responsible for sudden oak death and other plant diseases.

The pear-bait method involves placing unripe d'Anjou pears in recently irrigated plant containers. If Phytophthora is present in the soil, the zoospores are attracted to the pear tissue and cause visible lesions within a few days. These samples are sent to the California Department of Food and Agriculture for lab analysis.

This testing ensures that every batch of plants leaving our nursery is free of harmful pathogens before they are outplanted in sensitive restoration sites across California's watersheds.