The quality of infested trees is hard to improve, even with good chemical control and proper nutrition. Chemical control of rosette bud mites requires good coverage and proper timing. Spray droplets must hit all the new growth. Because of this, it is easier to successfully treat younger trees. There is no need to treat trees to be harvested that year.
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.