Tormentil
Scientific name: Potentilla erecta (L.) Raeusch.
Diagnostic features
Perennial with basal leaf-rosette (often withered by flowering) and erect to procumbent non-rooting flowering stems to 45cm.
Leaves ternate, sessile or nearly so, with 2 stipules resembling small leaflets.
Flowers all or nearly all with 4 petals, few to many in loose terminal cymes, 7-15mm across.
Carpels 4-20.
Achenes glabrous.
Habitat
Native; grassland and dwarf-scrub on heaths, moors, bogs, mountains, roadsides and pastures, mostly on acid soils but sometimes on limestone.
This species is keyed out on Page 2291 in the Text Key.
Key to the subspecies:
a. Stems to 25cm; stem-leaves serrate in distal 1/2 only, with teeth less than 1.5mm, the uppermost leaf c.6-16mm; petals 2.5-4.5mm; fruiting pedicels 6-30mm.
................................. Potentilla erecta erecta.
b. Stems 15-45cm; stem-leaves serrate for most of length, with teeth more than 1.5mm, the uppermost leaf 12-30mm; petals 4-6mm; fruiting pedicels (12)20-50mm.
...................... Potentilla erecta strictissima.
Hybrids
- Potentilla x suberecta Zimmeter (= Potentilla erecta x Potentilla anglica) occurs frequently with the parents in British Isles. It resembles Potentilla erecta in habit but the stems may rarely root at nodes late in the season and it is intermediate in leaflet-, petal- and carpel-number, petiole-length and flower-size. It is partially fertile, with less than10 achenes per flower. Chromosome number: 2n=42. |
