By Bill Kleiman
Purple coneflower, Echinacea purpurea is a wonderful native plant, but it is out of range, out of place for Nachusa. We have the E pallida, pale purple coneflower. Years back, the nursery that sold us the invasive Lespedeza (see earlier post) also sold us the wrong Echinacea. We now rarely buy seed. Since we have the occurrences of this “exotic” in just a few small patches I continue to treat them to try to drive them to zero.
The E purpurea is above, with a can of blue tree marking paint, and a Stihl SG11 hand sprayer with a standard 20% solution of Garlon 4 in basal bark mineral oil carrier.
Above is Aeroe brand tree marking paint. Nelson brand is also fine. These paints are made to mark things. Much better than paints for metals or other things.
I spray a small amount of the basal bark mix where the plant emerges from the ground. I cut off the flower heads. I sprayed half a dozen blue to find them later to see what happened.
This photo is typical. Four weeks after treatment all plants appeared dead. Collateral damage is modest. You will recall from an earlier post that this method also worked well on birdsfoot trefoil, Lotus corniculatus. I could have chosen to foliar spray, or perhaps dig them up.