Sisymbrium altissimum (Tumbling Mustard) - photos and description

 

 
Leaf upper stem in above photo.

 
Leaf mid stem in above photo.


Lower stem leaf in above photo.


Pod in above photo.

General: Annual plants with a much-branched growth habit. Stems are sparsely pubescent with long hairs.

Flowers: Flowers pale yellow in terminal clusters. We measured a flower at 15 mm diameter.

Leaves: Upper leaves differ considerably from the lower leaves. The upper leaves are pinnate, divided into thread-like segments. The upper leaf highlighted in the photo above was 4 cm long by 2.5 cm wide, divided into 7 segments. Lower leaves are pinnately lobed into lanceolate or oblong segments. We measured a lower stem leaf at 11 cm long by 5 cm wide, the end lobe almost divided to the midrib.

Fruit: The pods are spreading and can be so long and thin as to resemble branches. We measured a pod at 9.5 cm long by 1 mm wide, and this pod had a stalk 10 mm long.

Height: Height listed in Budd's Flora to 100 cm, we measured plants to 56 cm tall.

Habitat: Fields and waste ground.

Abundance: Common.

Origin: Introduced.

How to identify this plant: 1) Pale yellow flowers about 15 mm in diameter 2) Upper leaves pinnatifid into narrowly linear segments 3) Pods 5 to 10 cm long.

When and where photographed: Photos taken July 20th, edge of gravel pit, prairie grassland, about 400 km west of our home in Regina, SK.