How to Identify Poisonous Plants

Conium Maculatum - contains several poisonous alkaloid chemicals. All parts of the plant are poisonous. Hemlock resembles many other harmless members of the parsley family; however, its smooth, purple-blotched stems and unpleasant smell can easily identify it. Hemlock is found by roads, streams and on waste ground throughout Britain. It is less common in the north.



HORSETAIL - Equisetum - poisoning though rare is most likely to occur from contaminated hay or straw. The effects are similar to Bracken poisoning. They are extremely difficult to kill as they have very long taproots.



IVY - Hedra - clambers over trees and in hedgerows often reaching a great size, it produces greenish-yellow flowers in the autumn and is rarely eaten by horses and ponies.



MOULDY HAY/HAYLAGE/ SILAGE/CERIALS - contain toxins and bacteria produced fungi in 'big bale' silage has been associated with the death of several horses.

NIGHTSHADE (DEADLY/WOODY) - Atropa belladonna/Solanum dulcamara -Woody nightshade grows in woods and hedges and on beaches throughout Britain.



Deadly nightshade though rare is found in hedges, woods and thickets on chalky soils and sometimes near old buildings. These plants are members of the potato family; every part of the plant is poisonous, containing alkaloid poisons that attack the nervous system.



OAK TREES - Quercus - Both the leaves and acorns of the tree are poisonous. Some horses/ponies may develop an appetite for acorns with serious consequences, however the consumption of small amounts is probably harmless; but to be safe fence off any oak trees during the autumn.



RAGWORT - perhaps has the highest profile in plants dangerous to horses. Ragwort is a member of the daisy family and is so called because of their ragged leaves and appears in four varieties.



MARSH - Senecio aquaticus - is found in damp pasture, especially on peaty soil.



HOARY - S.erucifolius - is found on lime rich soils especially clay, in lowland areas of England and Wales. It can be identified by its hairy leaves and stems and grows between 30cm-120cm (1ft-4ft).



OXFORD - S.aqualidus - is becoming common especially around towns. It grows 22cm-37cm (9ins. -15ins.) and its flowers brighten the corner of a building plot. It was introduced to Oxford from southern Italy and was first noticed spreading elsewhere in 1794. This ragwort begins to bloom in May.



COMMON - S. Jacobaea - grows throughout the British Isles, growing on waste ground, roadsides and neglected pasture.



YEW- Taxus baccata - is the most poisonous tree in the British Isles and even small amounts are fatal. Yew trees grow especially well on chalk. They resist pollution well and can flourish in the shade of taller trees, but little will grow in the shade they themselves cast. The bark is poisonous and so is the cut or dropped foliage. The scarlet berries are harmless, but the seeds are poisonous.



Any garden plants and lawn mowing should be considered poisonous and unsafe for horses and ponies to eat. Some poisonous plants become palatable after spraying with weed killer.


The major causes of poisonings in horses and ponies are:
Ragwort,
Bracken,
Yew,
Oak.

Not all poisonings are fatal; sometimes the result can be serious digestive upsets, stupors or convulsions.


As a general rule poisoning should be suspected when the horse becomes suddenly ill after feeding; especially when put out to pasture for the first time in the season, the grass is scarce, but succulent young growth of poisonous plants is tempting. During dry periods when the grass is parched, or in the autumn/winter when grass is short and extra feed is not provided horses will eat what is available even if it has a bitter taste or is something they would not normally eat.


If you suspect your horse of having eaten parts of poisonous plants or trees, or the horse shows any unusual symptoms call your vet immediately.