Grecian Foxglove

Common Name: Grecian foxglove, woolly foxglove
Scientific Name: Digitalis lanata Ehrh.
Related Species: D. lamarckii auct. balcan.; D. purpurea L.; D. grandiflora Mill.; D. lutea L.
 

Legal Status

Prohibited Eradicate

All above and below ground parts of the plant must be destroyed. Additionally, no transportation, propagation, or sale of this plant is allowed. Failure to comply may result in enforcement action by the county or local municipality. 

Background

Grecian foxglove is native to central and southern Europe. It was brought to North America as an ornamental then escaped cultivation. In Minnesota, it is invasive and displaces desirable vegetation. Grecian foxglove is a threat to Minnesotans and is poisonous to humans, livestock, and wildlife.

Description

• Grecian foxglove is a perennial plant. It forms a rosette in its first year, then bolts and produces a single flowering stem its second and subsequent years.
• Flowering stems are unbranched and grow 2to 5 feet tall. They produce many tubular flowers arranged in an elongated cluster. Flowers are creamy white to pale yellow with brownish-purple veins inside.
• Leaves are simple, alternate, and oblong-shaped with pointed tips. Flowering stems and calyxes are covered with woolly hairs.
• Plants flower in summer. The flowers are pollinated primarily by bees. After flowering, oval seed pods are produced.
• This species reproduces only by seed and produces large quantities of seed.
• Common garden foxglove (D. purpurea) can be distinguished by its lack of woolly hairs on stems and calyxes. Its leaves are more rounded, and flowers exhibit a wide range of colors. Garden foxglove has not been reported as invasive in Minnesota. Multiple Digitalis species can hybridize, but no hybrids have been reported in Minnesota.

Habitat

Grecian foxglove thrives in habitats ranging from hot, dry Mediterranean sites to cool, moist, high-altitude sites in the Himalayas. Reported infestations in Minnesota and Kansas are in open sunny roadsides, residential yards, grasslands, river bluffs, and forest edges.

Means of spread and distribution

Not knowing its negative potential, gardeners planted Grecian foxglove as an ornamental. Established populations produce large amounts of seed that can be spread by wind, water, vehicles, humans, wildlife, and by moving seed-containing soil. All reported infestations in Minnesota are in Hennepin and Washington counties.

Impact

Grecian foxglove is toxic to humans, livestock, and wildlife. Grecian foxglove cut and dried in hay can poison livestock. This species is also invasive and displaces desirable vegetation such as forage and native plants.

Prevention and management

• Do not plant Grecian foxglove or move soil that may contain its seeds. Avoid direct contact with the plant to reduce the risk of toxin absorption through the skin. Wear protective clothing and rubber gloves when handling this species.
• Hand-pulling is not recommended due to toxicity concerns and disposal issues. However, repeated hand-pulling in spring and fall can control very small populations. Pulling larger populations may result in disturbed areas that are ideal for Grecian foxglove seedlings to germinate.
• Frequent mowing over multiple years may help control this species if flowering is prevented. Grecian foxglove can flower and produce seed on a short stem after mowing. Because of this, preventing all flowering may be a challenge.
• Annual herbicide applications in spring and/or fall can reduce Grecian foxglove populations over time. For specific herbicide recommendations, check with your local University of Minnesota Extension agent.
• For all management methods, it is important to monitor several years after treatment due to germination from the Grecian foxglove seedbank.

Toxicity

All parts of Grecian foxglove are poisonous in both fresh and dried forms. Cardiac glycosides from Grecian foxglove include digoxin and digitoxin and primarily affect cardiovascular, neurologic, and gastrointestinal systems. Ingesting plant parts or absorbing compounds through skin in direct contact with Grecian foxglove may adversely affect humans and other mammals and may be fatal. Smoke from burning plants may also be toxic.