Charlock - Sinapis arvensis, alt = ketlock, kedlock, yellows, wild mustard.
Rough hairy annual, medium hight with large lower leaves irregularly lobed. Upper leaves narrpow pointed. Small yellow flowers Apr-Oct with four petals, opposite. Widespread native arable weed especially on lime.
Picture of Charlock
PS = mustard oils
Toxicity – seed only
- Humans – no reports.
- Livestock – digestive disturbances if large quantites eaten when in seed, or if seed becomes encorporated into cake or meal.
Page top Go Back one stage Home Page plant index
Comfrey - Symphytum officinale, - see also Rough Comfrey and Russian Comfrey below.
Softly hairy grey-green plant with large lower leaves growing up to one metre tall. Small flowers produced in clusters May-June variable in colour from mauve to pink to creamy white. Found alongside water courses, in damp places and on roadside verges. Occasional native, southern. - but see also Russian Comfrey, below.
Picture of Comfrey
PS = Pyrrolizidine alkaloids in all parts of plant, but more concentrated in younger leaves, and persisting in dead plants. Toxic nitrites formed from accumulated nitrates in Rough Comfrey (Symphytum asperum - large blue flowers, red in bud - garden escape origin SW Asia.)
Toxicity –
- Humans – no reports, but see medicinal preparations below.
- Horses – no reports in Britain, but symptoms have been observed in horses overseas from related plants of the same family (Boraginaceae). Hound's tongue (Cynoglossum officinale) in hay produced liver damage, and skin pigmentation after exosure to light. Blue viper's bugloss (Echium plantagineum) caused lethargy and unco-ordinated movement, followed by blindness and death in some cases.
- Pasture animals – unlikely to become affected at pasture, but if fed in hay or other conserved feed, toxicity possible.
- Pigs - difficult breathing and blueish mouth from nitrite-nitrate poisoning after eating Rough Comfrey.
- Cattle, sheep, goats, deer, rabbits, dogs, cats, poultry – no reports.
Medicinal preparations still made from Comfrey as a tea drink, in spite of some health concerns arising from experimental feeding of large quantities of Comfrey extracts to rats over a long period resulting in liver tumours.
ADDITIONAL COMMENT – Russian Comfrey (Symphytum x uplandicum = S.officinale x S.asperum hybrid and garden escape), very similar in appearance to Comfrey and difficult to distiguish from when not in flower, is the commonest Comfrey of roadside verges. Flowers are blue to blue-purple and less variable. Russian Comfrey and other related Comfreys should be regarded with suspicion.
Page top Go Back one stage Home Page plant index
|
