In western Colorado, home to the treasured Palisade peach, cytospora canker is one of the most economically consequential fungal diseases faced by growers. A recent survey conducted by Colorado State University in Orchard Mesa found that 100% of the orchards have trees infected with cytospora canker. In some orchards, you can smell the sweetness of gummosis, the sweet oozing of sap from a tree that occurs from injury, stress, pathogen infection or insect damage. We are part of a team of fruit tree growers, extension personnel and researchers who are developing tools for mitigating cytospora canker in fruit tree orchards in Colorado and Utah. In a study we published, we estimate this disease results in at least $3 million in annual economic losses for growers in Colorado. In infected large branches, which are called scaffolds, the damage can result in a 50% loss of peaches per tree. Peaches were first planted in Palisade and Grand Junction in 1882 by one of the first white settlers to the area, John Harlow.…