Phenological Study and Management of Red Fescue (Festuca rubra) in Wild Blueberry

Abstract

Red fescue is a perennial rhizomatous and sod forming turf grass species that is a newly emerging weed in wild blueberry fields of Nova Scotia. There is no published information on the impact, phenology and effective control management of red fescue in wild blueberry. A two year field study was conducted to study red fescue growth dynamics in wild blueberry fields, identify effective herbicides and maximize herbicide efficacy with proper application timing. Results indicate that if wild blueberry fields were maintained free of red fescue from May through October that the red fescue population reduced declined in the following year. Between 60 to 80% emergence of red fescue occurred at around 160 GDD before emergence of wild blueberry which occurred at 222-265 GDD and reached peak height between 850 to 920 GDD. Most of the spring applied herbicide increased berry yield comapared to control, but glyphosate also controlled red fescue (60-80%). Propyzamide was also effective in a fall application trial with 99% control with minimal risk of crop damage. We recommend fall applications of propyzamide followed by spring application of glyphosate, if substantial red fescue survives to the following spring.