BLACK MUSTARD

Brassica nigra

Cabbage Family [Brassicaceae]

month8may month8jun month8june month8jul month8july month8aug month8sep month8sept

status
statusZnative
flower
flower8yellow
inner
inner8cream
morph
morph8actino
petals
petalsZ4
stem
stem8round
stem
stem8square
sex
sexZbisexual

8th June 2016, Near Alien Spaceship, Blundellsands, Sefton Coast. Photo: © RWD
The main stem stands upright up to 2m high. The upper stem leaves are oval(ish) but not lobed; the middle leaves have lobes at the base of the leaf or (further down the stem) several pinnate lobes on the leaf petiole (stalk).


8th June 2016, Near Alien Spaceship, Blundellsands, Sefton Coast. Photo: © RWD
Side branches are alternate and well separated, usually with a long thin (broader lower down the plant) oval leaf (bract?) just beneath the junction.


8th June 2016, Near Alien Spaceship, Blundellsands, Sefton Coast. Photo: © RWD
Larger stem leaves may have teeth (centre left) and might narrow to their base, but do not clasp the stem.


8th June 2016, Near Alien Spaceship, Blundellsands, Sefton Coast. Photo: © RWD
Flowers near and at the summit of the growing branches.


8th June 2016, Near Alien Spaceship, Blundellsands, Sefton Coast. Photo: © RWD
Linear leaves beneath the branch junctions near the summit.


8th June 2016, Near Alien Spaceship, Blundellsands, Sefton Coast. Photo: © RWD
Flowers have the usual 4 petals for Brassica species. As-yet un-opened flower pods green. The growing fruit are closely appressed parallel to the stem and very thin at first.


8th June 2016, Near Alien Spaceship, Blundellsands, Sefton Coast. Photo: © RWD
Flowers all yellow apart from green filaments with four slightly paler yellow anthers on.


8th June 2016, Near Alien Spaceship, Blundellsands, Sefton Coast. Photo: © RWD
The lower leaves.


9th Aug 2016, River Alt, Hightown, Sefton Coast. Photo: © RWD
Later in the season, the plant has all gone pale straw coloured with the fruit now ripe.


9th Aug 2016, River Alt, Hightown, Sefton Coast. Photo: © RWD


9th Aug 2016, River Alt, Hightown, Sefton Coast. Photo: © RWD
The dried fruit pods. They have a long pedicel (3 to 8mm long) leading to a broader linear pod with four slight bulges where the 4 seeds are located with. The style part at the top (which is less than 4mm long) has a short taper (beak) to the stigma which can hardly be discerned.


9th Aug 2016, River Alt, Hightown, Sefton Coast. Photo: © RWD
The seeds are blackish (hence the 'black' in both the common name Black Mustard and the specific epithet of the binomial - nigre) with much finer ridges on than fingerprints on the palm of your Authors hand. It seems that these basal leaves disappear when the plant is much taller - they are not to be found in the other photos.


17th April 2015, River Dee, Aldford, Cheshire. Photo: © RWD
Earlier in the year the basal leaves are much more in prominence, with, your Author surmises, the 7 vascular bundles in the stem being translated into 7 major veins on the leaves. Some basal leaves are pinnately lobed at their base.


17th April 2015, River Dee, Aldford, Cheshire. Photo: © RWD
The basal leaves are similar to those of Charlock, but with differences.


17th April 2015, River Dee, Aldford, Cheshire. Photo: © RWD
Some leaves have (irregular) teeth.


Not to be semantically confused with : Swiss Treacle-mustard Erysimium rhaeticum, Spreading Treacle-mustard Erysimiumrepandum, Ball Mustard (Neslia paniculata), Tower Mustard (Turritis glabra), Hare's-ear Mustard (Conringia orientalis), Chinese Mustard (Brassica juncea), Treacle Mustard (Erysimum cheiranthoides), White Mustard (Sinapi alba), Hoary Mustard (Hirschfeldia incana), Russian Mustard (Sisymbrium volgense), Hedge Mustard (Sisymbrium officinale), Horned Mustard (Sisymbrium polyceratium), Garlic Mustard (Alliaria petiolata) [plants with similar names and probably similar hot taste but in differing genera of the Brassicacea family]

It is to be found on disturbed or rough ground, waste places, beside streams and rivers or on sea cliffs, as it is not afraid of heights.


  Brassica nigra  ⇐ Global Aspect ⇒ Brassicaceae  

Distribution
 family8Cabbage family8Brassicaceae
 BSBI maps
genus8Brassica
Brassica
(Cabbages)

BLACK MUSTARD

Brassica nigra

Cabbage Family [Brassicaceae]