When spraying spruce trees, the insecticide/fungicide must be applied at high pressure, so the spray penetrates the inner branches and webbing. A second application may be required two weeks after the initial spray.
Products registered for commercial purposes are intended for use by commercial applicators only, not by individual homeowners. There are currently no products for needle disease with domestic registration for application by individual homeowners.
In conjunction with the use of fungicides, mowing of grass around the trees to keep humidity levels low, removal of all fallen needles from the base of tree (to reduce levels of the pathogen) and avoiding pruning or shearing of trees during wet weather (to avoid spreading spores of the fungus) will also reduce the impact of needle cast disease. When pruning or shearing, at any time, tools should be sterilized between cuts by dipping in 70% alcohol for 3 minutes.
Needle disease is one explanation for the browning of needles in spruce but there can be other factors to consider such as environmental and site factors, insect infestations and stem diseases. Be sure to have an accurate diagnosis prior to starting a control program for needle disease.
If you have trees that need to be sprayed, we can custom spray them for you. Our A1 mist sprayer uses a high velocity air stream instead of water to transport the chemical. The chemical is pumped through nozzles into the air stream creating a fine/coarse mist, which allows us to push the mist to a target area.
If you would like a custom spraying quote or if you are interested in purchasing an A1 mist sprayer, please contact Tyson at 306-621-3100.