Cherry Tree Spray
The skill of the person applying the spray has an important role in minimizing the impact of the material used. Spray when the wind is still or nearly so. Know how much spray you need to cover the tree so that you don't mix up too much and have a disposal problem. Use protective clothing, rubber boots, use unlined plastic or rubber gloves.
Know what pests you are spraying for, and the various spray material options.
The major insect pests are plum curculio and spotted wing drosophila. Plum curculio is active from when the fruit are about 1/2 inch in diameter until about the 2nd week of June. Some locations are not bothered by this insect.
Probably the safest material is "Surround", which has kaolin clay as the active ingredient. This material will not work unless the tree and fruit are completely covered, so multiple sprays are needed on the tree prior to plum curculio egg laying.
Spotted wing drosophila is an aggressive fruit fly that can cause larvae in the fruit.
See the following article, especially the section mentioning kaolin clay and spinosad for this insect.