Turritis glabra (Tower Mustard) - photos and description
Plants growing on a mossy, rocky hillside
Pods slightly elevated to perpendicular to the stem
Pods more or less circular in cross section
Basal leaf in above photo
Stem leaves with a diamond shaped base
Stem leaves oblong, sessile
General: Biennial plants with stout stems. The stems are glabrous towards the top, hirsute below.
Flowers: Flowers small, racemose, have four petals, are white with purple colouring at the tips. We measured flowers at 12 mm long and 6 mm wide.
Fruit: Circular in cross section or nearly so, narrow, usually straight, we measured a fruit at 31 mm long by 1 mm wide.
Leaves: Lower leaves whorled, upper leaves crowded on the stem. Leaves have a prominent mid-rib. Basal leaves with petioles, oblanceolate to oblong, measured to 20 mm long by 6 mm wide including petiole. Basal leaves are grey with appressed hairs. Stem leaves alternate, clasping, elliptical to ovate, often have a diamond-shaped base, measured sat 15 mm ong by 5 mm wide.
Height: Height listed in Budd's Flora to 60 cm, we measured plants to 20 cm tall.
Habitat: Cliffs, thickets, woods, and fields.
Abundance: Listed as fairly common in Checklist of the Vascular Plants of Saskatchewan. I think I have only seen this plant in the Cypress Hills.
Origin: Native.
Synonym: Listed in many of the field guides we use as Arabis glabra.
How to identify this species: Fruit terete (circular in cross section) or nearly so.
When and where photographed: Photos were taken May 7th, 11th, and May 17th on a rocky slope in the Cypress Hills 400 km southwest of our home in Regina, SK.