Controling Bracken Ferns
How to eliminate Bracken Ferns along the side of a road. Ferns are destroying road by penetrating surface. Best method or herbicide to apply?
Luce County Michigan
The herbicide that will work the best and you can buy is glyphosate. It comes with several brand names like "Roundup" and others. It may not work as well later in the season if the plants are beginning to shut down. If they are growing well and green, it's better. If you buy glyphosate as a concentrate, mix by label instructions. Do not reduce the water, thinking that it will work better. It will not.
You may have to spray more than once but give it about a week and see how much is brown. Watch for new shoots and spray immediately.
Next spring, watch for shoots and spray immediately. The longer you wait, the harder it is to get control. Keep in mind that bracken fern spreads by rhizomes so if there are plants too close, eventually rhizomes will be back to send up more plants.