Is a topical application of a highly refined petroleum product that has a additive emulsifier to allow it to mix. These oils kill exposed insects and mites by either suffocating (asphyxiation) them or by directly penetrating the cuticle and destroying internal cells. Best applied before bud break in ideal temperatures (40-70 degrees) in less than 6mph. of wind for full coverage. Plants under stress, especially drought could have increased risk of injury from this spray.
Other plants that are sensitive to oil sprays are;
Evergreens, Smoke Tree, Japanese Maples, Red Buds and Hickories, annual flowers
There are many issues with spraying as you can read. The chances of successfully getting full coverage are unlikely, there is no residual and the price for application is usually high. There is no gauge of success and you generally require more sprays throughout the growing season.
ALTERNATIVE THAT WORKS
How about an alternative that works; works longer , kills more damaging insects, leaves the beneficial insects safe, is cost effective and has full coverage season long.
We have been working with systemics now going on 10 years. And it all makes sense with added benefit; applied in the dormant season as a soil injection along with a slow release nitrogen fertilizer it will protect from damaging insects, increase health and vigor all growing season long.
The Tree Doctor
A tree doctor brings specific experience and expertise to your issue, adding to the accurate diagnosis and treatment of tree problems, helping to ensure healthy trees and plants for years to come. These Arborist should be licensed through the state and hold other designations validating there knowledge.
Dormant Oil (shot gun spray)