In France, the species is reported from more than 1,000 localities and is found in the Alps, Pyrenees, eastern and Mediterranean area and is only absent in the west and northwest. In Italy, it occurs in the Alps and northern Apennines. It is common in the Czech Republic in mountains and is scattered in all of Slovenia with small local populations. It occurs in most of Denmark's lowlands in the mainland and in the west. In Norway and Sweden there are hundreds of localities. In Switzerland, the species can be found over more than 50% of the country.
In Ukraine, it grows in the Carpathian Mountains. Single isolated populations were founds in the 19th and first half of the 20th century in the lowland part of Ukraine (Lvivska and Zytomirska regions) but are now likely to be extinct.
In Bulgaria, the only evidence for the species presence is a single herbarium sheet from the Rila mountains without further specifications of the locality. Its presence is therefore considered doubtful.
Habitat and Ecology
The species occurs in the following habitat types of the Habitats Directive (Commission of the European Communities 2009):
- 4030 European dry heaths
- 6230 Species-rich Nardus grasslands, on silicious substrates in mountain areas (and submountain areas in Continental Europe)
- 4060 Alpine and boreal heaths
- 9430 Subalpine and montane Pinus uncinata forests
- 7140 Transition mires and quaking bogs
IUCN Red List Assessment
Red List Category
Red List Criteria
EU 27 regional assessment: Least Concern (LC)
Arnica montana is widespread in Europe and is found at hundreds of localities. The populations are stable in some countries and declining in other parts of its range. The reasons for this decline are partly due to collection of the plant for medicinal purposes and partly due to habitat loss. This plant is found mainly in acidic and nutrient poor grasslands and shrublands, a habitat that changes among others due to abandonment of grazing activities or fertilisation to use the land for agriculture. The species is currently classed as Least Concern as it is too abundant to be at risk of extinction in the near future, however the population trends should be monitored.
In Luxembourg, it used to be locally quite common in grazed grasslands and heaths and was formerly known from 14 localities whereas now only four populations remain. The current populations show no establishment of seedlings.
Another threat is coming from agriculture. Here the application of fertilisers to grassland in order to increase the ph, such as limestone dust, decrease the suitability of the habitat for Arnica montana that naturally prefers nutrient-poor soils. The abandonment of grasslands leads to a change in vegetation such as mosses and tall plants that can outcompete Arnica montana. A change of grazing from cattle to sheep impacts the species although it is generally well adapted to grazing as it has flat leaves on the ground. Reforestation also reduces the habitat available to Arnica montana.
In some areas skiing is affecting the species as it causes soil compaction.
There are protection measures in place for some European countries and it features in some national red lists:
- In Bosnia-Herzegovina and Croatia it is classed as Vulnerable on the national red lists.
- Czech Republic: protected by national Law and included in national parks and protected landscape areas.
- France: protected in several regions (Aquitaine, Centre, Bourgogne) and more than five departements, included in several protected areas.
- Germany: Classed as Vulnerable (level 3) on the German Red List (Ludwig and Schnittler 1996).
- Hungary: classed as Extinct in the Wild on the national red list
- Italy: not on the national red list but some populations are in regional parks and prevents regional collection by law.
- Lithuania: classed as Vulnerable, protected according to national and regional law.
- Luxembourg: classed as Critically Endangered on the national red list.
- Slovenia: classed as Vulnerable on the 2002 red list, protected by law which it prevents from being collected. Several localities are in protected areas such as Natura 2000 sites, national parks, regional parks.
- Sweden: classed as Near Threatened on the Swedish red list 2010.
- Switzerland: classed as Least Concern on Swiss Red List (Moser et al. 2002) but regionally found in protected areas. Collections are accepted but there are rules about the amount.
- Ukraine: included in the 1996 Red Data Book of Ukraine, but not included in the 2009 edition of this book. It is protected in the Carpathian biosphere reserve, in the Tapichirkiskij, Urochychcze Zatinky, Teresjanka, Chorkyj Dil, Stebnyk protected areas, and in the nature monument Verchnje Ozerychere.
Distribution and habitat 
Arnica montana is endemic to Europe, from southern Iberia to southern Scandinavia and the Carpathians. It is absent from the British Isles and the Italian and Balkan Peninsulas. A. montana grows in nutrient-poor siliceous meadows up to nearly 3,000 metres (9,800 ft). It is rare overall, but may be locally abundant. It is becoming rarer, particularly in the north of its distribution, largely due to increasingly intensive agriculture. In more upland regions, it may also be found on nutrient-poor moors and heaths.
A. montana has tall stems, 20–60 centimetres (7.9–24 in) high, supporting usually a single flower head. Most of the leaves are in a basal rosette, but one or two pairs may be found on the stem and are, unusually for composites, opposite. The flower heads are yellow, approximately 5 cm in diameter, and appear from May to August.
Uses and toxicity 
Arnica montana is sometimes grown in herb gardens and has long been used medicinally. It contains the toxin helenalin, which can be poisonous if large amounts of the plant are eaten. It produces severe gastroenteritis and internal bleeding of the digestive tract if enough material is ingested. Contact with the plant can also cause skin irritation. The roots contain derivatives of thymol, which are used as fungicides and preservatives and may have some anti-inflammatory effect. When used topically in a gel at 50% concentration, Arnica montana was found to have the same effect when compared to a 5% ibuprofen gel for treating the symptoms of hand osteoarthritis.
A scientific study found that the application of topical arnica had no better effect than a placebo in the treatment of laser-induced bruising.
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- Delilah Alonso, Melissa C. Lazarus & Leslie Baumann (2002). "Effects of topical arnica gel on post-laser treatment bruises". Dermatologic Surgery 28 (8): 686–8. doi:10.1046/j.1524-4725.2002.02011.x. PMID 12174058. Retrieved January 27, 2008.