Twin Arnica
Arnica sororia
Wallace Keck
Taxonomy
- Division:
- Magnoliophyta | - Flowering plants
- Family:
- Asteraceae
- Genus:
- Arnica
- Species:
- Arnica sororia
Growth Characteristics
- Life Cycle:
- Perennial
- Growth Habit:
- Forb/herb
- Height:
- 1-2 ft
- Light Requirements:
- Full Sun
- Drought Tolerance:
- High
- Bloom Months:
- may, jun, jul
- Bloom Colors:
- Orange, Yellow
Native Range
United States: California, Idaho, Montana, Nevada, Oregon, South Dakota, Utah, Washington, Wyoming, Canada: Alberta, British Columbia, Saskatchewan
Reported Fauna Sightings
Soil Requirements
- Soil Type:
- rocky, well-drained, nutrient-poor soil
- pH:
- 5.5 - 7.5 (slightly acidic to neutral)
- Drainage:
- excellent drainage required
- Moisture:
- dry to moderate
- Notes:
- native to mountainous regions, prefers open, sunny areas
Germination Information
Pre-treatment: Seeds should be cold, moist stratified for 60-90 days at 37°F. Seeds that have been dry stored for a few months may not require a stratification treatment, although a short cold moist treatment will likely improve germination uniformity.
Establishment: Seed is collected when the pappus expands, usually in late July or early August. Seed is wind disseminated but does not blow away easily. The fruits are achenes that are dark brown and 4 to 6 mm long at maturity; with a pappus of white hairs at the apex. Seeds are usually mature by the end of July to early August and are quickly dispersed by wind.
Source: npn.rngr.net