Most lawn weed killers, including weed and feed, kill broad leaf weeds, or broad leaf plants.
- Your trees are giant weeds.
- General application of weed killer to your lawn is an application of poison for your trees.
- Spot treat weeds under tree canopies, but target treat ONLY the weeds.
- If there are no weeds, don’t apply weed killer.
Ironically, I could find a lot online about how Roundup kills trees but little about broad leaf weed killers. This is misinformation. There is some evidence that Roundup can be absorbed through bark but it has limited negative impact on trees. This misinformation campaign comes from activist groups.