[The Mustard Family East of the Cascade Mts. of Oregon and Washington]

Rockcresses: The Genera Arabis and Boechera East of the Cascade Mountains of Oregon and Washington

Small-leaved Rockcress: Arabis microphylla

Waldo Rockcress: Arabis aculeolata (Synonym: Arabis aculeolata var. aculeolata) -

Cross-haired Rockcress, Wetsoil Rockcress: Arabis crucisetosa - Fruits erect to ascending. Flowers white with petals from 6-8 mm long. Plants 10-40 cm tall.

Eschscholtz's Hairy Rockcress, Hairy Rockcress, Mountain Rockcress, Pacific Coast Rockcress: Arabis escholtziana (Synonyms: Arabis hirsuta, Arabis hirsuta var. eschscholtziana, Arabis hirsuta var. glabrata) - Fruits flattened and ascending or spreading. Flowers greenish white, cream or pinkish, the petals 4-5 mm long. Plants 15-100 cm tall.

Cascade Rockcress, Forkhaired Rockcress, Fork-haired Rockcress: Arabis furcata (Synonym: Arabis furcata var. furcata) - Fruits erect to ascending. Flowers white with petals from 5-10 mm long. Plants 20-40 cm tall.

Creamflower Rockcress: Arabis pycnocarpa (Synonyms: Arabis hirsuta, Arabis pycnocarpa ssp. pycnocarpa, Arabis hirsuta var. pycnocarpa) -

Elegant Rockcress, Purple Sicklepod Rockcress, Sicklepod Rockcress, Sickle-pod Rock Cress: Boechera atrorubens (Synonyms: Arabis atrorubens, Arabis sparsiflora, Arabis sparsiflora var. atrorubens) -

Brewer's Rockcress: Boechera breweri ssp. shastaensis -

Calder's Rockcress: Boechera calderi (Synonyms: Arabis lyallii, Arabis lyallii var. lyallii) -

Cascade Rockcress: Boechera cascadensis -

Cobre Rockcress, Masonic Rockcress: Boechera cobrensis (Synonyms: Arabis cobrensis, Arabis cobrensis var. cobrensis) - Fruits recurved. Flowers white or pink, the petals 4-5 mm long. Plants less than 30 cm high.

Cusick's Rockcress, Red Rockcress: Boechera cusickii (Synonym: Arabis cusickii) - Basal and stem leaves strongly ciliate. The arched fruits are spreading. Flowers white to bright purple, the petals 7-9 mm long.

Davidson's Rockcress: Boechera davidsonii (Synonyms: Arabis davidsonii, Arabis davidsonii var. davidsonii) -

Spreading Rockcress, Spreadingpod Rockcress, Spreading Pod Rockcress: Boechera divaricarpa (Synonyms: Arabis divaricarpa, Arabis xdivaricarpa var. divaricarpa, Arabis xdivaricarpa var. interposita, Arabis drummondii x holboellii, Arabis interposita) - Curved fruits are erect to ascending lower on the racemes and spreading high on the racemes. Flowers white or pinkish, the petals are 4-8 mm long. Plants are 30-80 cm tall.

Hells Canyon Rockcress: Boechera hastatula (Synonym: Arabis hastatula) -

Howell's Flatseed Rockcress: Boechera howellii (Synonyms: Arabis howellii, Arabis platysperma, Arabis platysperma var. howellii) -

Lemmon's Rockcress: Boechera lemmonii (Synonyms: Arabis lemmonii, Arabis lemmonii var. lemmonii) - Fruits widely spreading to curved downward. Petals rose-purple. Plants 10-20 cm tall. Plants of high elevation.

Lyall's Rockcress, Lyall's Slender Rockcress: Boechera lyallii (Synonyms: Arabis lyallii, Arabis lyallii var. lyallii, Arabis murrayi) -

Littleleaf Rockcress, Little-leaf Rock Cress, Small-leaved Rockcress: Boechera microphylla (Synonyms: Arabis microphylla, Arabis microphylla var. macounii, Arabis microphylla var. microphylla, Boechera microphylla var. microphylla) - Fruits straight to mostly curved, ascending to spreading. Flowers pale pink to purple, the petals 5-8 mm long. Plants 10-30 cm tall. Found at lower elevations.

Pioneer Rockcress, Broad-seeded Rockcress: Boechera platysperma (Synonyms: Arabis platysperma, Arabis platysperma var. platysperma) - Eastward to eastern base of the Cascade Mountains.

Mount Adams Rockcress: Boechera paddoensis (Synonym: Arabis lemmonii var. paddoensis) -

Hairystem Rockcress, Sicklepod Rockcress, Small-flowered Rockcress: Boechera pauciflora (Synonyms: Arabis campyloloba, Arabis holboellii, Arabis holboellii var. pinetorum, Arabis perelegans, Arabis sparsiflora, Arabis sparsiflora var. columbiana, Arabis sparsiflora var. subvillosa, Boechera pauciflora, Boechera sparsiflora var. subvillosa) -

Lyall's Rockcress, Lyall's Slender Rockcress: Boechera paupercula (Synonyms: Arabis lyallii, Arabis lyallii var. lyallii, Arabis lyallii var. nubigena, Boechera lyallii) - Fruits straight and nearly erect. Flowers purple, the petals 6-8 mm long. Plants 10-25 cm tall.

Dropseed Rockcress, Holboell's Rockcress: Boechera pendulocarpa (Synonyms: Arabis exilis, Arabis holboellii, Arabis holboellii var. pendulocarpa, Boechera exilis) -

Woodland Rockcress, Holboell's Rockcress: Boechera pinetorum (Synonyms: Arabis holboellii, Arabis holboellii var. pinetorum, Boechera holboellii) -

Many-flowered Rockcress: Boechera polyantha (Synonyms: Arabis holboellii, Arabis holboellii var. retrofracta, Boechera holboellii) -

Meadow Rockcress: Boechera pratincola (Synonym: Arabis x divaricarpa) -

Hoary Rockcress: Boechera puberula (Synonym: Arabis puberula) - Fruits reflexed and pendant. Flowers rose-colored to purplish. Plants 15-50 cm tall.

Holboell's Rockcress, Reflexed Rockcress, Secund Rockcress: Boechera retrofracta (Synonyms: Arabis holboellii, Arabis holboellii var. retrofracta, Arabis holboellii var. secunda, Arabis retrofracta, Arabis secunda, Boechera holbellii, Bochera hoboellii var. secunda) -

Sicklepod Rockcress, Black-flowered Rockcress, Elegant Rockcress: Boechera sparsiflora (Synonyms: Arabis arcoidea, Arabis peramoena, Arabis polytricha, Arabis sparsiflora, Arabis sparsiflora var. peramoena, Arabis sparsiflora var. sparsiflora, Boechera sparsiflora var. sparsiflora) - Pedicels in fruit spreading. Fruits ascending to spreading. Flowers pink to purplish, the petals 8-15 mm long. Plants 30-100 cm tall.

Canadian Rockcress, Drummond's Rockcress: Boechera stricta (Synonyms: Arabis albertina, Arabis brachycarpa, Arabis confinis, Arabis connexa, Arabis drummondii, Arabis drummondii var. connexa, Arabis drummondii var. oxyphylla, Arabis oxyphylla, Boechera angustifolia, Boechera brachycarpa, Boechera drummondii, Erysimum drummondii, Turritis drummondii) - Fruits erect. Flowers pink, the petals 7-12 mm long. Plants 30-80 cm tall.

Ashy Rockcress: Boechera subpinnatifida (Synonym: Arabis subpinnatifida) -

Woody Rockcress: Boechera suffrutescens (Synonyms: Arabis suffrutescens, Arabis suffrutescens var. suffrutescens) - Fruits over 3.5 mm wide and pendulous. Flowers pruplish, the petals 5-9 mm long. Plants 15-50 cm tall. Plants of high elevations.

Tower Mustard, Tower Rockcress: Turritis glabra (Synonyms: Arabis glabra, Arabis glabra var. furcatipilis, Arabis glabra var. glabra) - Fruits erect and glabrous. Flowers yellowish-white or cream, the petals 3-6 mm long. Plants 30-150 cm tall.


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