Hybrid Clover
Trifolium hybridum
Horse
Severe
Any suspected ingestion is an immediate veterinary emergency. Prolonged consumption (several weeks) in a pasture where this clover is dominant (>20% of the flora).
Equio informs, it does not diagnose. When in doubt, call your vet.
What to do now
- Antidote
- No specific antidote. Intensive liver support and symptom management (photosensitization).
- Time to signs
- Several days to several weeks of continuous exposure
- Prognosis
- Grave if the liver is already affected to the point of causing neurological symptoms. Good if intervention occurs at the stage of skin burns.
- Immediate veterinary emergency.
- Remove the horse from all sun exposure.
- Place the horse in a dark, isolated stable.
- Perform emergency liver function tests.
- Initiate long-term liver support treatment.
Its ID card
- Height
- 30 cm – 1 m
- Flowering
- June to September
- Toxic parts
- Leaves and flowers.
- Toxin
- Poorly defined hepatotoxins (and associated fungi).
- Habitat
- Sown pastures (old forage formulas), moist, cool, clay soils.
- Soil indicator
- Heavy, moist soils, resistant to cold.
- Regions
- Northern, Central, and Western Europe, North America
- In hay
- Yes — stays toxic once dried
- Palatability
- Very palatable! Horses love it, which makes it all the more dangerous (massive intoxication).
When the risk rises
Spring and Summer (active growth and strong sunlight).
Spotting it in the field
White clover (purely white flower, creeping stem, leaf with a white V) or Red clover (large purple flower). Other clovers can cause minor issues (salivation) but are infinitely less serious. — smell : slightly sweet and herbaceous odor, not very pronounced when crushed.
- Resembles a large white clover.
- Upright stem (unlike creeping white clover).
- Bicolored flowers, white at the base and turning pink towards the top.
- Leaves LACK the typical white V-shaped mark found on other clovers.
Signs to watch for
Chronic (cumulative) toxicity with potentially acute effects during high exposure.
Dose : Significant daily consumption over several weeks (>20% of the diet)
- Severe, oozing sunburns on unpigmented skin (photosensitization)
- Jaundice (yellow mucous membranes)
- Colic, diarrhea, major weight loss
- Severe ulcerative lesions in the mouth
- Neurological signs (constant yawning, head pressing, blindness) linked to liver failure
Who is affected
Other species : Curiously, cows and sheep are very insensitive to it and consume it very well. It is a specific poison to equids.
In pregnant mares : major risks of toxemia for the mare.
Getting rid of it
Method : Manually pull the plant before flowering, wearing gloves. Avoid overgrazing which can promote its growth. Use weed control methods if necessary, ensuring horse safety.
- Identify and eradicate hybrid clover from pastures intended for horses.
- Carefully check the composition of forage seed mixtures.
- Avoid sowing mixtures containing hybrid clover for equids.
- Monitor pastures for any appearance of this plant.
Frequently asked questions
Can Equio identify Hybrid Clover from a photo?
It can help organize visual clues, but plant identification must remain cautious when horse health is at stake.
Is Hybrid Clover dangerous in hay?
This entry flags hay vigilance. Isolate suspicious forage and ask for professional advice if exposure is possible.
This page is informational. If ingestion is likely, if signs appear, or if the horse is fragile, contact a veterinarian immediately.