Northern Prairie Wildlife Research Center
Western Wetland Flora
Field Office Guide to Plant Species
Polemonium occidentale Greene
- Family: Phlox (Polemoniaceae)
- Flowering: June-August
- Field Marks: This Jacob's-ladder differs from others by its 11-27 lanceolate toothless leaflets, its solitary stems, and the petals about twice as long as the tube of the petals.
- Habitat: Along streams, swamps, wet places in the mountains.
- Habit: Perennial herb from rhizomes.
- Stems: Solitary, upright, smooth or glandular-hairy, up to 3 feet tall.
- Leaves: Alternate, pinnately compound with 11-27 leaflets; each leaflet lanceolate, pointed at the tip, tapering to the base, up to 1 3/4 inches long, up to 1/2 inch wide, without teeth, smooth or glandular-hairy.
- Flowers: Several crowded into a branched but narrow inflorescence, subtended by lobed or toothless bracts.
- Sepals: 5, green, united to form a cup, glandular-hairy, up to 1/2 inch long, the lobes about as long as the teeth.
- Petals: 5, blue, united about 1/2-way to form a tube, 1/2-3/4 inch long, the lobes longer than the tube.
- Stamens: 5, attached to the tube of the petals.
- Pistils: Ovary superior; styles exserted beyond the petals.
- Fruits: Capsules ovoid, about 1/8 inch long, with several elongated seeds.
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