We have a White-tailed deer problem. They will eat almost everything we plant in our gardens. Unless we routinely use a commercially available repellant, our plants are fodder to these four-legged munchers. Motion-sensing lights go on and off all evening as they cross the yard looking for the next tasty Day Lily flower.

A few years back, we attended a seminar given by Donald Leopold, author of “Native Plants of the Northeast.” In this talk, Don held up a blank sheet of paper and stated, tongue in cheek “Here’s a list of plants deer won’t eat.”

We have observed a number of plants in our woodland garden that emerge every spring and survive the deer until winter for one reason or other. Some natives have evolved with harmful, distasteful or odorous chemicals that repel deer. One such chemical is calcium oxalate. Plants with crystals of this chemical seem to repel herbivores such as deer and hungry rabbits. Oxalate crystals can cause pain and swelling when coming in contact with skin or the mouth. Seems we have native plants which contain this compound growing in our back forty:

Skunk Cabbage is visible very early in the spring. When bruised, the foliage stinks, which may be the deterrent. Curiously, the plant has thermogenic property, meaning it creates enough heat to actually melt snow and ice, allowing its flowers and leaves to emerge before other herbaceous plants, to take advantage of early pollinating flies. This, of course attracts deer hungry for something green after a long winter. Skunk Cabbage contains calcium oxalate which keeps the deer at bay. They seem to know the dangers of nibbling on its greenery, or perhaps tried a bite and learned a lesson.

Jack-in-the-Pulpit is another plant we find in many places in our woodland garden that the deer will let be. It too contains crystals of calcium oxalate. In the fall we collect seeds from these plants to propagate. Always, however, we wear Nitrile gloves to prevent the crystals from embedding in our fingers and causing us harm.

Curiously, Purple Trillium plants are also found in select spots in our woods. That they thrive is also due to the fact that Purple Trillium leaves contain calcium oxalate. The deer leave them alone. Not true for White Trilliums. None of these beauties survive in our woodland. Deer will eat them to the ground in our propagation bed, with no ill effect, if we fail to spray them every few weeks with a repellant.

One patch of White Trilliums grows among Foam Flowers (Tiarella), which is a good deer repellant. If we don’t protect them, the Trilliums get eaten and the Foam Flowers are left untouched. Apparently, the natural astringent contained in the fuzzy leaves of Foam Flower keep them uneaten.

The emerging fiddleheads of Ferns are edible, but also fuzzy. The deer leave them alone.

Other native perennials have evolved with toxic chemicals that act as deer repellant, such as Red Baneberry and Doll’s Eyes. Both produce bitter berries that contain a number of chemicals that are extremely toxic when eaten. While some birds consume the berries unharmed, deer have either figured out the toxicity or are simply repelled by the bitter taste. Neither species is bothered. Both can be found in our woodland garden.

Some plants not only taste bad, but smell bad as well. The deer leave Wild Leeks alone. These onion relatives not only smell any deer foolish enough to taste one will have bad breath for a week. It seems to work that way if I eat them. They are stronger than garlic. One particular patch of Wild Leeks in a remote corner of our property shares the ground with a colony of Bloodroots, which the deer will usually eat. These early spring ephemerals gain some protection apparently, from this association with the Wild Leeks.

In conclusion, deer issues are a frustrating matter for gardeners, but there is some hope without serious intervention. Consider some of these native perennials for your woodland garden as a partial solution.

Cornell Cooperative Extension Oneida County answers home and garden questions which can be emailed to homeandgarden@cornell.edu or call 315-736-3394, press 1 and ext. 333. Leave your question, name and phone number. Questions are answered weekdays, 8 a.m. to 4 p.m. Also, visit our website at http://cceoneida.com/ or phone 315-736-3394, press 1 and then ext. 100.