羊菊属属

This circumboreal and montane (subalpine) genus occurs mostly in the temperate regions of western North America, with a few species native to the Arctic regions of northern Eurasia and North America.

Arnica species are used as food plants by the larvae of some Lepidoptera species, including Bucculatrix arnicella.

Arnica was previously classified in the tribe Senecioneae because it has a flower or pappus of fine bristles.

Arnica is the basis of a homeopathic remedy promoted for aiding bruise recovery.

Characteristics

Arnica plants have a deep-rooted, erect stem that is usually unbranched. Their downy opposite leaves are borne towards the apex of the stem. The ovoid, leathery basal leaves are arranged in a rosette.

They show large yellow or orange flowers, 6–8 cm (2–3 in) wide with 10–15 cm (4–6 in) long ray florets and numerous disc florets. The phyllaries (a bract under the flowerhead) has long spreading hairs. Each phyllary is associated with a ray floret. Species of Arnica, with an involucre (a circle of bracts surrounding the flower head) arranged in two rows, have only their outer phyllaries associated with ray florets. The flowers have a slight aromatic smell.

The seedlike fruit has a pappus of plumose, white or pale tan bristles. The entire plant has a strong and distinct pine-sage odor when the leaves of mature plants are rubbed or bruised.

Arnica montana

The species Arnica montana, native to Europe, has long been used in folk medicine, but there is no clinical evidence for its homeopathic use as an effective therapy.

Toxicity

Arnica montana contains the toxin helenalin, which can be poisonous if large amounts of the plant are eaten, and contact with the plant can also cause skin irritation. Medical preparations can cause skin irritation if applied topically, and adverse effects include headache and drowsiness if ingested. High doses can have severe adverse effects including death.

Species

Accepted species:

Arnica acaulis—Common leopardbane—eastern US from Alabama to New Jersey

Arnica angustifolia—Narrowleaf arnica—Canada (from British Columbia to Quebec), US (Montana, Idaho, Wyoming, Colorado); Russia, Scandinavia

Arnica cernua—Serpentine arnica—California, Oregon

Arnica chamissonis—Chamisso arnica—US west of Rockies including Alaska; Canada (British Columbia to Quebec plus Yukon + Northwest Territories)

Arnica cordifolia—Heart-leaf leopardbane, heartleaf arnica—US West of Rockies plus Alaska + Michigan; Canada (from British Columbia to Quebec plus Yukon + Northwest Territories)

Arnica dealbata—California

Arnica discoidea—Rayless arnica—California, Oregon, Nevada, Washington

Arnica fulgens—Foothill arnica, orange arnica, shining leopardbane—USA (west of Rockies plus Michigan); Canada (from British Columbia to Manitoba)

Arnica gracilis—Smallhead arnica (A. latifolia x A. cordifolia)—US (Montana, Idaho, Wyoming, Colorado, Oregon, Washington); British Columbia, Alberta, Northwest Territories

Arnica griscomii—Russia, Canada, Alaska

Arnica intermedia—eastern Russia (Yakutskiya, Khabarovsk, Magadan)

Arnica lanceolata—Arnica, lanceleaf arnica—US West of Rockies plus Alaska, Maine New Hampshire, Vermont, New York; Canada (British Columbia, Quebec, New Brunswick)

Arnica latifolia—Broadleaf arnica—western US, western Canada

Arnica lessingii—Nodding arnica—Kamchatka, Alaska, Yukon, Northwest Territories, British Columbia

Arnica lonchophylla—Longleaf arnica—most of Canada; Alaska, Montana, Minnesota, South Dakota

Arnica longifolia—Longleaf arnica, spearleaf arnica—US west of Rockies, British Columbia, Alberta

Arnica louiseana—Lake Louise arnica—British Columbia, Alberta

Arnica mallotopus—Honshu Island in Japan

Arnica mollis—Hairy arnica, wooly arnica——US West of Rockies plus Alaska, New Hampshire + Vermont; Canada (from British Columbia to Quebec plus Yukon + Northwest Territories)

• Arnica montana—Mountain arnica—most of Europe plus Greenland; naturalized in India
• Arnica nevadensis—Nevada arnica—California, Oregon, Nevada, Washington
• Arnica ovata—British Columbia Alberta, Yukon, US West of Rockies

Arnica parryi—Nodding arnica, Parry's arnica—British Columbia, Alberta, Yukon, US West of Rockies

Arnica porsildiorum—Kamchatka, Yukon, Northwest Territories

Arnica rydbergii—Rydberg arnica, Rydberg's arnica, subalpine arnica—British Columbia, Alberta, northwestern USA

• Arnica sachalinensis—Hokkaido, Sakhalin, Kurils, Irkutsk
• Arnica sororia—Twin arnica—British Columbia, Alberta, Saskatchewan, US West of Rockies
• Arnica spathulata—Klamath arnica—California, Oregon
• Arnica unalaschcensis—Alaska arnica—Hokkaido, Honshu, Kamchatka, Sakhalin, Kuril, Alaska
• Arnica venosa—Shasta County arnica—California
• Arnica viscosa—Mt. Shasta arnica—California, Oregon