Grecian Foxglove

By Tara Kelly, Director of Ecological Restoration

It may be the cool weather making me reflective this morning, but I can’t help but think about this past growing season. It’s always a bit of a sprint to stay on top of the weeds in our restorations when they all seem to demand attention at the very same time. Our staff did a fantastic job of managing the slew of invasive weeds this summer, but there’s one plant that I’m left feeling a little nervous about: Grecian foxglove (Digitalis lanata).

It’s quite an attractive plant with a spike of cream-colored tubular flowers. However, I recommend you resist the urge to pick this plant, as it is also quite poisonous. It contains a powerful cardiac glycoside, which in minute amounts can slow the heart and, in extreme cases, cause death. The glycoside, digoxin, is used to treat heart problems including atrial fibrillation. It is difficult to synthesize so Digoxin is still extracted from the plant, although commercial use is beginning to decline.

Grecian foxglove is very new to Minnesota and we’ve been managing small populations of this plant for a few years now. We pull what we can (while wearing gloves!), mow and spray what we can’t feasibly pull. But even given those efforts, this year’s crop of Grecian foxglove was impressive. Not impressive just in sheer numbers of plants, but in their locations.

In previous years, the flowers would emerge in late June in a few predictable locations. Like clockwork, we would return to those spots and remove the plants we found. This year, however, the foxglove plants were showing up in locations that never had a sign of foxglove before. I wondered if our equipment had been in those areas and inadvertently transported seed, but most of the new foxglove populations were in uncharted territory.

The most likely explanation is the transport of seeds in the fur of animals; the seed pods have barbs that can easily attach to fur or clothing. The life cycle of foxglove is biennial (growing vegetatively in its first year and flowering the next), so the transport of the seed to the new locations must have occurred two years ago if we saw the flowers this season.

Although nervous about this plant’s potential impacts, I am optimistic about managing this species. We were able to pull, mow or spray almost every population we knew about on the preserve. And we’re not the only ones with the plant on their radar screens. Grecian foxglove is one of only three invasive plant species that is on the Minnesota Department of Agriculture’s “Eradicate List”. As opposed to the “Controlled List”, the three species listed here for Minnesota are either not yet present in the state or are not widely established. In other words, we still have a fighting chance to make sure these species do not become a statewide issue. And we intend to continue to do our part in our neck of the woods here at the Belwin Conservancy.