Voles are small rodents also known as meadow mice that tunnel near the surface of the lawn and chew on tree bark, plant roots, seeds and stems. They are herbivores that can destroy plants at a rapid pace. They are sometimes confused with moles, but moles are generally disruptive only because of their tunneling. They do not eat plants, but instead feed on soil insects. Certain plants are helpful in creating a barrier around more susceptible plants because they are unappealing to voles.
Although they are not a common lawn plant, goldenrod is a species that voles tend to avoid if possible, according to the About Town website. This herbaceous perennial is generally found in pastures or other unpopulated areas of North and South America as well as parts of Europe and Asia.
Goldenrod is generally a tall, woody-stemmed plant with a bright yellow or “golden” flowers at the tip. Goldenrod relies on the wind for pollination and is therefore commonly blamed for allergies. It is also used medicinally and for food in some instances.
Daffodils are among the well-known toxic plants in the Narcissus genus that is resistant to voles for the same reasons it is resistant to deer and other herbivores, according to the "Seattle Post-Intelligencer." All Narcissus plants have a toxic chemical called lycorine in the bulbs or flowers that will keep pests at bay. In humans it can cause sickness if eaten as well. Exposure to the plant’s sap may also cause skin irritation.
Voles enjoy snacking on the bulbs of plants, but some bulb plants are particularly resistant to vole attack. One of those is the autumn crocus. This groundcover plant with purple flowers contains the toxic chemical colchicine. The flowers, seeds, bulbs and leaves of the autumn crocus contain the toxin and are powerful enough to kill humans if enough are ingested. According to the Sustainable Gardening website, some voles have died from eating the bulbs. Typically they will not try. The autumn crocus flowers in September and is unrelated to the spring blooming crocus, which is completely non-toxic.
The Lenten rose is a late-winter blooming perennial that will not provide a meal for local pests. Voles and deer both avoid this type of rose, and it is easy to care for, in addition to being pest resistant. According to "Southern Living," the Lenten rose requires little water and no fertilization to grow. It does not tolerate very wet conditions.