Treatment protects the buds, and the buds are only important to produce more shoots. Even treatment the year before sale may not be economically feasible. Scout trees, from the second year in the field until trees are 5 feet, in the fall in areas prone to rosette buds to determine if treatment will be needed the following spring. Dimethoate 4 EC marketed by Drexel Corporation is the only effective, legal pesticide to use against the rosette bud mite. It is only labelled for application with a high-pressure sprayer.
Good coverage is essential for good rosette bud mite control.
Trees should be sprayed from two opposing sides using a heavy fog pattern, as opposed to the straight stream pattern commonly used for balsam woolly adelgid control. From 300 to 500 gallons per acre are required depending on the spacing, height, and density of the trees. Complete coverage of the most current growth is required for control. Treatment can continue through the third week in June. Because growth is tender when trees are treated for the rosette bud mites, foliage burn can result.