[The Mustard Family East of the Cascade
Mts. of Oregon and Washington]
Blue Mustard, Chorispora, Crossflower, Purple Field Mustard
Chorispora tenella
Synonyms: Chorisporum tenellum, Raphanus tenellus
The photo above shows a close-up of the flower of blue mustard as seen from Wilson Creek, BLM lands about 10 miles southwest of Wilbur, WA...........April 30 2,007.
The photos on this page show
the pod and flowers of Chorispora tenella about 20
miles SW of Toppenish, WA.........early May, 1997.
Characteristics:
Blue mustard is a leafy, spreading, annual, branched from the base, and rising
from 10-50 cm in height. The herbage, as seen in the photo at right, consists
of stalked glands. The leaves are oblanceolate to elliptic-oblong, with sinuous
or coarsely-toothed leaf edges. The lower leaves are petiolate, the uppermost
are sessile, with the blades from 3-8 cm long. The leaves are nearly entire
to sparsely toothed.
The sparsely flowered racemes are elongated, with the lower flowers from the
axils of the upper leaves. The narrow, tubular calyx is 6-8 mm long. The pedicels
are short and stout. The pale purple flowers each have 4 narrow petals about
6-8 mm long. The siliques are widest at the base, narrowing gradually to a point
at the tip. They are about 3.5-4.5 cm long, arched, and spreading or ascending
(See photo at right.).
Habitat:
Blue mustard is found in cultivated areas where it reduces crop
yields, and in open, disturbed places.
Range:
Although it is a native of Russia and southwestern Asia, it
is now established as a weed in the drier inland parts of the Pacific Northwest.
Importance:
Blue mustard is a weedy species which has a disagreeable odor which may be transferred
to the milk of dairy animals when they eat the plant.
The photo above shows the upper stem of blue mustard as seen near the Odessa Craters near Odessa, WA........April 28, 2007.
The photo above shows a close-up sideview of the flower of blue mustard as seen near the Odessa Craters near Odessa, WA........April 28, 2007.
The photo above shows a close-up of the seed pod of blue mustard as seen near the Odessa Craters near Odessa, WA.........April 28, 2007.
The photo above shows the underside of a stem leaf of blue mustard as seen near the Odessa Craters near Odessa, WA.........April 28, 2007.
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Blue mustard as seen at left along the Hard Stone Trail at Cottonwood Canyon State Park on the west bank of the John Day River.........March 19, 2017. The photo at right shows blue mustard along Dry Creek about one mile upstream from Wenas Creek, DNR lands in Yakima County, WA......May 29, 2022.
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Additional images of blue mustard as seen near the Odessa Craters near Odessa, WA..........May 8, 2012.
Paul Slichter