Fauna
Flower

Thorow-wax

Bupleurum rotundifolium

Also known as Hare's Ear, Hound's Ear, Round-leaved Hare's-ear, Perfoliate Hare's-ear

Thorow-wax derives its historic name from its distinctive perfoliate foliage, where the stem appears to pierce directly through the middle of each round, waxy leaf. Clusters of tiny sulfur-yellow flowers bloom in midsummer, nestled above prominent yellowish-green bracts that mimic petals. Once an abundant companion plant in traditional Eurasian grain fields, it has declined in parts of its native arable range while establishing itself casually in disturbed soils abroad.

AnnualWildflowerSun-Loving
Thorow-wax reference1 / 7
(c) Sam Kieschnick, some rights reserved (CC BY) · cc-by
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Least ConcernConservation statusIUCN Red List categoriesLCNTVUENCREWEXLeast ConcernRed List categories, explained →
Key facts
Diet & preyPhotosynthesis via sunlight, water, and soil minerals
Predators
  • Aphids
  • Caterpillars
  • Slugs
ThreatsHerbicide application and mechanized agricultural seed cleaning
HabitatsArable field margins, roadsides, disturbed ground, and chalky slopes
Life spanAnnual (1 growing season)
Classification
  1. OrderApiales
  2. FamilyApiaceae
  3. GenusBupleurum
  4. SpeciesBupleurum rotundifolium
Range & activity
Range data is not available yet.
Safe observation
Interaction riskLow
  1. Low
  2. Moderate
  3. High
  4. Very high
Why interaction risk is low
Safe to observe at a normal distance.
Responsible observation
  • Leaf Inspection: Look closely at where the upper leaves clasp entirely around the stem without a stalk.
  • Bloom Timing: Search dry, calcareous field edges from June to August to spot the yellow floral bracts.
Related species
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