Maureen from Red Deer writes
Established shelter belt of blue spruce. Heavy infestation with stinkweed and thistle. Spending hundreds on labor, curtail, and Roundup just to deal with it again the following year. Tried it this late fall. Not easy to get out in early spring because of the field location.
Casoron 4G Herbicide is not labeled for evergreens. We recommend using Resolute 65 WG Prodiamine Herbicide (Generic Barricade) for pre-emergent control. We also recommend you contact your local Master Gardener for a specific recommendation that won't harm the trees. They can be reached by clicking on the link below and selecting your state and county. Please let us know if you need help locating the product that they recommend or if you would like to place an order.
http://www.csrees.usda.gov/Extension/
Answer last updated on: 04/04/2023
