categoryZCrops Crops List 

WHITE MUSTARD

Sinapis alba

Cabbage Family [Brassicaceae]

month8may month8jun month8june month8jul month8july month8aug month8sep month8sept

category
category8Crops
status
statusZarchaeophyte
flower
flower8yellow
morph
morph8actino
petals
petalsZ4
type
typeZclustered
stem
stem8round
stem
stem8ribbed
sex
sexZbisexual

19th June 2012, the beech, Abbotsbury, Dorset. Photo: (CC by 2.0) Geoff Toone
Grows to 70cm long but occasionally up to 1m.


19th June 2012, the beech, Abbotsbury, Dorset. Photo: (CC by 2.0) Geoff Toone
The flowers are yellow with petals between 7.5 to 14mm long. Of much more importance to their identification is the shape of the seed pods below the flowers.


24th June 2019, Whittington, Lichfield. Photo: © Mike Baldwin
The seeds within the pods number between 2 and 8. The pods are anything between 2 and 4.2 cm long. The most striking feature of the pods though is their 10 to 24mm (up to 30mm) flattish and curved extension beyond the seeds (which is called the beak). They are also usually hairy.


24th June 2019, Whittington, Lichfield. Photo: © Mike Baldwin
The seeds are near the stalk end of the pods, you can see their bulges. Beyond them is the curved, flattish beak which tapers to the tip. The pods are usually populated by short, stiff hairs but might be hairless.


19th June 2012, the beech, Abbotsbury, Dorset. Photo: (CC by 2.0) Geoff Toone
The pods measure between 2cm and 4.2cm and have between 2 to 8 seeds. The rest of the pod has a long uniform taper to the style at the tip when younger, but this flattens later on. [Two other pods on this specimen are apparently empty and very narrow (either that or they are yet to develop?)].


24th June 2019, Whittington, Lichfield. Photo: © Mike Baldwin
The seed pods seem to be hairiest where the bulges of the seeds within are located, and less elsewhere. Their brownish tip is the remains of the stigma. Some pods above those seem to be empty, perhaps those were not fertilised or they still have to develop(?).


19th June 2012, the beech, Abbotsbury, Dorset. Photo: (CC by 2.0) Geoff Toone
The seeds pods usually curve on the flat area where there are no seeds and fewer hairs.


19th June 2012, the beech, Abbotsbury, Dorset. Photo: (CC by 2.0) Geoff Toone
The stems are slightly ribbed and have short, still downwardly directed hairs.


Uniquely identifiable characteristics; a brassicaceae where the seeds pods are curved nearer the tapering end where there are no seeds.

The leaves of the plant, not shown much here, are deeply pinnately lobed. Photos wanted.

Grown as a fodder plant, a green manure or for making table mustard it is found either naturalised or as a casual on arable fields or on tips, waysides or waste places. It prefers calcareous soils and is scattered over most of the British Isles whilst being absent from much of the north but seems to prefer the east side of the UK and Ireland mostly avoiding the western sides especially Western Scotland.


  Sinapis alba  ⇐ Global Aspect ⇒ Brassicaceae  

Distribution
 family8Cabbage family8Brassicaceae
 BSBI maps
genus8Sinapis
Sinapis
(Mustards)

WHITE MUSTARD

Sinapis alba

Cabbage Family [Brassicaceae]