Scenarios for exposure of aquatic organisms to plant protection products in the Netherlands. Part 3, Spray applications in avenue tree nurseries and downward spraying underneath fruit trees

A new exposure assessment methodology for various tree crops and application methods was developed by Wageningen UR and PBL Netherlands Environmental Assessment Agency. In addition to the scenario for upward and sideways spraying in fruit orchards, which was published in 2021, this report describes the methodology for upward and sideways spraying in avenue tree nurseries and downward spraying in such nurseries and in fruit orchards. The new procedure calculates the exposure concentration based on a statistical distribution of the exposure concentration in all relevant Dutch watercourses. The methodology results in a so-called 90th percentile exposure concentration considering all watercourses alongside fruit orchards or avenue tree nurseries. The methodology accounts for the exposure by plant protection products through spray drift, drainage and atmospheric deposition. The scenarios include drift-reducing application techniques and crop-free buffer zones. With the scenarios in this report and the report on upward and sideways applications in fruit orchards, a more realistic exposure assessment is possible for edge-of-field watercourses next to fruit orchards and avenue tree nurseries regarding both upward & sideways applications and downward applications in the Netherlands.