During the past 10 years, orchard practices in Kentucky have changed dramatically. Many of these practices contributed to conditions conducive for diseases and pests. Growers began to shift from traditional plant spacing to high density plantings, increasing tree stress and humid microclimates conducive for diseases. Smaller trees, however, reduce pruning labor and enable better spray coverage as compared with larger tress. Cultivar selection has changed with consumer demand, and with each shift in cultivar comes new challenges, such as increased disease susceptibility. Additionally, new and emerging pests/diseases present different challenges, while many pesticides and fungicides have been discontinued and new ones have entered the market.
Innovative new tools and technologies have been adopted by some of the more progressive growers, thus reducing inputs and resulting in more precise pesticide applications. For example, pheromone traps combined with trapping data can help growers identify thresholds before insecticide applications. During the past 4 years, the University of Kentucky Fruit IPM Working Group has updated and streamlined the UK AgWeather Plant Disease and Insect Prediction Model site to assist grower decision-making. Growers also have access to university-produced printed publications, virtual information, and social media sites. The University of Kentucky Fruit IPM Working Group has developed specific recommendations and practices that are suitable for the unique conditions present in Kentucky.
Variations in farm size, grower practices, crop selection, business models, and available resources result in a variety of farm types across the Commonwealth. A recent survey of growers indicated that actual on-farm practices varied greatly from grower to grower and from those recommended by University of Kentucky State Extension Specialists. Table 1 compares grower practices to University of Kentucky pest management recommendations which are applicable for this point in the season.
- A Profile of Commercial Apple Production in Kentucky 2017 (Link)
- Backyard Apple Disease & Pest Management Using Cultural Practices (with Low Spray, No Spray, & Organic Options) (PPFS-FR-T-21)
- Effectiveness of Fungicides for Management of Apple Diseases (PPFS-FR-T-15)
- Fruit, Orchard, and Vineyard Sanitation (PPFS-GEN-05)
- IPM Scouting Guide for Common Problems of Apple (ID-219)
- Midwest Fruit Pest Management Guide (ID-232)
- Scouting Guide for Problems of Apple Mobile Website (Apple Scout)
- Simplified Backyard Apple Spray Guides (PPFS-FR-T-18)
By Kim Leonberger, Plant Pathology Extension Associate and Nicole Gauthier, Plant Pathology Extension Specialist