Rick from Albany, Or writes
Tree was in early stage (class 2) infection. All branches are now drooping despite recommended watering and occasional green leaves are being lost. Drench treated a 50 ft., four trunk birch for bronze borer w/ Merit 2nd week of May.
With a systemic application of a product like Merit to the root zone, it can take a couple of weeks for a large to tree to complete aborb and have the ingredients translocate all the way through the plant. Some borers once they have started damage to a tree do such quick harm to it that the tree cannot be salvaged or saved even with the strongest insecticides. Below is a link to information on the bronze birch borer and the average timing, life cycle and treatments that can be used.
Answer last updated on: 07/03/2015