Polemonium pectinatum

Polemonium pectinatum
Imperiled
Imperiled (NatureServe)
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Asterids
Order: Ericales
Family: Polemoniaceae
Genus: Polemonium
Species:
P. pectinatum
Binomial name
Polemonium pectinatum

Polemonium pectinatum is a species of flowering plant in the phlox family known by the common names Washington Jacob's-ladder and Washington polemonium. It is endemic to the state of Washington in the United States, where it occurs in the Columbia Basin, including the Channeled Scablands and the Palouse.

Description

This perennial herb grows from a taproot, producing a cluster of stems up to 80 centimetres (31 in) tall. The alternately arranged leaves are each made up of several linear-shaped leaflets up to 5 centimetres (2.0 in) long. The hairy, glandular inflorescence is an open array of white or lavender flowers with five corolla lobes. Flowering occurs in May through July.

Species

This species occurs in riparian habitat and seasonally moist depressions and bottomlands. Other species in the habitat may include Crataegus douglasii, Amelanchier alnifolia, Elymus cinereus, Rosa woodsii, and Ribes aureum.

There are about 26 occurrences of this species, divided into 6 or 7 populations. The plant's total distribution covers less than 2,500 acres (1,000 ha).

Threats to the species include overgrazing, though it can tolerate some grazing activity, being adapted to disturbance. Land use conversion is a threat, for example, the conversion of the Palouse grasslands to agriculture. Other threats include alterations in hydrology, herbicides, and introduced species.

References

  1. 1 2 3 4 5 6 7 NatureServe. "Polemonium pectinatum". NatureServe Explorer. Arlington, Virginia.
  2. 1 2 "Polemonium pectinatum". Washington Burke Museum.
  3. ↑ "Polemonium pectinatum". Center for Plant Conservation. Archived from the original on 29 October 2010.