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ARS Home » Pacific West Area » Corvallis, Oregon » Horticultural Crops Research » Research » Research Project #438641

Research Project: Pesticide Rate Needed for Protection of Interior Canopies from Boxwood Blight

Location: Horticultural Crops Research

Project Number: 2072-22000-043-49-G
Project Type: Grant

Start Date: Aug 1, 2020
End Date: Oct 31, 2021

Determine the rate of water needed to adequately penetrate and cover various boxwood canopies.

A planting of 3 boxwood cultivars will be utilized for coverage trials. The evergreen boxwood cultivars include Buxus microphuylla japonica ‘Winter Gem’, Buxus sempervirens ‘Suffruticosa’ and Buxus x ‘Green Velvet'. The ‘Suffruticosa’ is tightly sheared while in comparison the others have a more open canopy. A standard 50 gallon Pak-blast Rears air blast sprayer will be used. This sprayer has been retrofitted with the Intelligent Spray System (a Lidar laser sensor, Doppler speed sensor, embedded computer, and individual pulse width modulation solenoid valves). The sprayer will be operated in both standard and Intelligent (ISS) mode. A flow meter will also allow for precise calculation of spray volume. Coverage will be evaluated utilizing water sensitive cards (TeeJet Technologies, Wheaton, IL) clipped back-to-back with a sign holder (VersaGrip, Deflecto LLC, Indianapolis, IN). Cards will be placed inside and in the lower half of each canopy evaluated. Spray volume rates from 50 to 400 gal/A will be evaluated for how well spray cards are covered in the center of these boxwood canopies using the sprayer in both standard and ISS mode. The entire sprayer will be transported to at least one commercial nursery to evaluate coverage on nursery grown boxwood plants. Ideally plants grown in containers as well as in the field will be evaluated at similar gal/A.