SafePlants

Cross Mountain Rockcress

This page provides information about the Cross Mountain Rockcress, including its classification, synonyms, and distribution.

Considerations for Pets

• The plant belongs to the family Brassicaceae (mustard family).

Scientific Name and Common Names

• Scientific Name: Arabis williamsii var. saximontana (Rollins) Rollins
• Common Names: Cross Mountain Rockcress, William's Rockcress

Taxonomy and Nomenclature

• Family: Brassicaceae (Mustard Family)
• Synonyms:
  • Boechera saximontana (Rollins) Windham & Al-Shehbaz
  • Arabis williamsii Rollins var. saximontana (Rollins) Rollins
• Alternative Scientific Names: Arabis arenosa, Arabidopsis arenosa

Distribution and Habitat

• Found in the USA, specifically in Idaho (ID), Montana (MT), and Wyoming (WY).
• Grows in mountainous regions.
• A shale-barren rockcress occurs sporadically in mid-Appalachian Mountain ranges at an elevation of 1300 to 1500 feet.
• Suggests similarities to climates of northern Finland.

Morphological Characteristics and Growth Habits

• Type: Forb/herb
• Life Cycle: Biennial/Perennial
• Can be grown in gardens throughout the whole year.
• Tolerates very harsh minimum temperatures, even below zero.
• The aerial part may be lost during the coldest temperatures.

Ecological Role

• The plant cross-breeds with thale cress (Arabidopsis thaliana).
• Fungal gametes stick to the pollinators, who facilitate cross-pollination and increase the

Interactions with Other Organisms

• It cross-breeds with thale cress (Arabidopsis thaliana).
• Fungal gametes stick to the pollinators, who facilitate cross-pollination.

Resources and Further Information

• British Database of World Flora and Fauna (for taxonomic information)