Answer: Vinca minor is usually planted as a groundcover, and is often used in difficult spots (such as in competition with maple trees where grass and other plants can not grow) because it is such a resiliant plant. It is evergreen and produces charming blue flowers every spring about when the daffodils bloom. If you are sure you want to eliminate it, then an herbicide containing glyphosate should work if you are careful to read and follow the label instructions including allowing time for the chemical to translocate to the roots where it actually works to kill the plant. It may be necessary to repeat the application, too. Tilling will probably not help because it can distribute "cuttings" and roots throughout the soil where they may take hold to make even more new plants.
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