Plants Toxic to Chickens

Read this before the list

A list like this is easy to misread as "your garden is a minefield". It is not. Chickens with decent forage and full feeders are genuinely good at leaving bitter, acrid ornamentals alone, and plenty of keepers run flocks for years through gardens containing half the plants below without incident.

What that means is that the plant being present is rarely the problem. Real poisonings almost always trace back to one of three situations:

• Clippings and prunings tipped into the run. This is the most common route by a wide margin. A flock will strip a fresh heap of greenery out of curiosity in a way it would never strip the living hedge — and yew, oleander and milkweed all stay toxic after drying.
• Bulbs on the surface. Daffodil and tulip bulbs hold far more toxin than the leaves, and autumn planting and spring lifting are exactly when they end up loose on the soil.
• Nothing else to eat. A bored flock in a bare run, or birds turned onto ground where the toxic plant is the only green thing growing, lose the luxury of being fussy.

So the useful actions are narrow: walk your garden once and deal with the severe-tier plants, never compost hedge clippings where birds can reach them, and keep the run interesting enough that desperation never enters into it.

Can kill quickly (10)

A small quantity can be fatal, sometimes within hours and often with no warning signs beforehand. These are the plants worth actively removing from anywhere a flock can reach.

• Yew — Taxus spp.

  Toxin: Taxine alkaloids

  Stops the heart. Yew is among the fastest-acting plant poisons in veterinary medicine, and birds are usually found dead rather than found ill — there is often no window in which to act.

  Where you meet it: Hedging and churchyard trees. The classic route into a run is a bag of hedge clippings, which stay toxic after drying.

• Oleander — Nerium oleander

  Toxin: Cardiac glycosides (oleandrin)

  Disrupts heart rhythm, in the same way digitalis does but more aggressively. Every part of the plant is toxic, and it stays toxic dried.

  Where you meet it: A common ornamental hedge in warm climates. Prunings and fallen leaves are the usual problem.

• Castor bean — Ricinus communis

  Toxin: Ricin

  A potent cytotoxin that shuts down protein synthesis in the gut wall and beyond. The seeds carry by far the highest concentration.

  Where you meet it: Grown as a dramatic ornamental for its foliage. The seeds are the danger, and they scatter.

• Water hemlock — Cicuta spp.

  Toxin: Cicutoxin

  A violent neurotoxin causing seizures. It is widely described as the most poisonous plant native to North America, and the roots are the most concentrated part.

  Where you meet it: Wet ground — ditches, stream edges, boggy field corners a ranging flock can get to.

• Poison hemlock — Conium maculatum

  Toxin: Coniine and related alkaloids

  Progressive paralysis, ending in respiratory failure. Easily mistaken for cow parsley, which is how it gets left standing.

  Where you meet it: Roadsides, waste ground and field margins. Recognisable by purple blotches on the stem.

• Foxglove — Digitalis purpurea

  Toxin: Cardiac glycosides (digitoxin)

  Acts directly on heart muscle and disturbs rhythm. This is the plant the heart drug digoxin was originally derived from, at a dose nobody is controlling.

  Where you meet it: Cottage borders and woodland edges, and it self-seeds freely into places nobody planted it.

• Monkshood — Aconitum spp.

  Toxin: Aconitine

  A fast neurotoxin and cardiotoxin. The roots are the most concentrated part, which matters if a flock is scratching in a border.

  Where you meet it: Ornamental borders, grown for the tall blue hooded flowers.

• Lily of the valley — Convallaria majalis

  Toxin: Cardiac glycosides (convallatoxin)

  Heart rhythm disturbance, from a plant where leaves, flowers and the red berries are all toxic. The water from a cut arrangement is toxic too.

  Where you meet it: Shady borders and under hedges, where it spreads into dense mats.

• Azalea and rhododendron — Rhododendron spp.

  Toxin: Grayanotoxins

  Interferes with nerve and muscle cell function, producing weakness, collapse and cardiac effects. Leaves stay toxic after they fall.

  Where you meet it: Extremely common garden shrubs. Fallen leaves and prunings are the realistic exposure, not a bird eating a living bush.

• Laburnum — Laburnum anagyroides

  Toxin: Cytisine

  A nicotinic neurotoxin. The seeds in their pea-like pods are the most dangerous part, and they look exactly like something worth eating.

  Where you meet it: Ornamental trees, often overhanging exactly where people put a run for the shade.

Serious illness (9)

Causes real illness, and can kill in quantity or with repeated exposure. Worth fencing off rather than tearing out, unless a bored flock is stripping it.

• Nightshades (wild) — Solanum spp., Atropa belladonna

  Toxin: Solanine and tropane alkaloids

  Digestive and neurological signs. This is the same family behind the green-potato and tomato-foliage warnings, in wild species that concentrate it far more.

  Where you meet it: Hedgerows, waste ground and the edges of vegetable beds, where they self-seed readily.

• Jimsonweed — Datura stramonium

  Toxin: Tropane alkaloids (atropine, scopolamine)

  Neurological signs and, at feed-contamination levels, reduced growth and production. Seeds contaminating grain are a documented poultry problem.

  Where you meet it: Disturbed ground and, importantly, as a contaminant in poorly cleaned grain.

• Pokeweed — Phytolacca americana

  Toxin: Phytolaccatoxin and saponins

  Severe digestive irritation. The purple berries are attractive to birds, and the root is the most toxic part.

  Where you meet it: Field edges, fence lines and any neglected corner, where it grows tall and conspicuous.

• Bracken fern — Pteridium aquilinum

  Toxin: Ptaquiloside and thiaminase

  A chronic rather than acute poisoning: sustained intake destroys thiamine and causes bone marrow damage. The harm accumulates over weeks of grazing.

  Where you meet it: Rough grazing, woodland edges and hillsides, especially where a flock is ranged widely.

• Milkweed — Asclepias spp.

  Toxin: Cardiac glycosides

  Heart and nervous system effects. It stays toxic when dried, so it remains a problem in cut hay or cleared vegetation.

  Where you meet it: Meadows, pasture margins, and increasingly deliberate plantings for pollinators.

• Lantana — Lantana camara

  Toxin: Pentacyclic triterpenoids (lantadenes)

  Liver damage and photosensitisation. The unripe green berries are the worst part.

  Where you meet it: A warm-climate ornamental and, in some regions, an aggressive weed.

• Daffodil bulbs — Narcissus spp.

  Toxin: Lycorine and calcium oxalate crystals

  Violent digestive irritation. The bulb holds far more of it than the leaves or flowers.

  Where you meet it: Borders and lawns. Autumn planting and spring lifting are when bulbs end up loose on the surface where a flock can reach them.

• Tulip bulbs — Tulipa spp.

  Toxin: Tulipalin A and B

  Digestive irritation and, on contact, dermatitis. Again concentrated in the bulb.

  Where you meet it: The same situation as daffodils — planting, lifting, or a bird scratching a bulb up.

• Privet — Ligustrum spp.

  Toxin: Terpenoid glycosides

  Digestive upset and, in quantity, incoordination. Berries and leaves are both involved.

  Where you meet it: One of the most widely planted hedges there is, so clippings are the usual route.

Usually makes them ill (7)

Typically causes digestive upset or irritation rather than death. Common enough in gardens that knowing about it matters more than removing it.

• Hydrangea — Hydrangea spp.

  Toxin: Cyanogenic glycosides

  Digestive upset, and cyanide release in theory, though the quantity a bird would need to eat is large.

  Where you meet it: A very common garden shrub, usually growing right where the run went.

• Holly — Ilex spp.

  Toxin: Saponins (ilicin)

  Digestive irritation from the berries. The spiny leaves largely defend themselves.

  Where you meet it: Hedges and specimen shrubs; the berries drop in quantity over winter.

• English ivy — Hedera helix

  Toxin: Triterpenoid saponins and falcarinol

  Digestive upset from the leaves and berries, plus contact irritation.

  Where you meet it: Covering fences and walls, which frequently means covering the run itself.

• Elder (raw) — Sambucus spp.

  Toxin: Cyanogenic glycosides

  Digestive upset from the leaves, stems, roots and unripe berries. Ripe cooked berries are a different matter, which is why the plant has a culinary reputation at all.

  Where you meet it: Hedgerows and field corners, where it seeds itself freely.

• Buttercup — Ranunculus spp.

  Toxin: Protoanemonin

  Mouth and digestive irritation from fresh plants. Drying breaks the compound down, so cut and wilted buttercup is far less of a concern.

  Where you meet it: Damp pasture and lawns — one of the most common weeds a ranged flock will walk over daily.

• Boxwood — Buxus sempervirens

  Toxin: Steroidal alkaloids (buxine)

  Digestive upset. Boxwood is bitter enough that birds rarely persist with it.

  Where you meet it: Formal hedging and topiary, so once again the risk arrives as clippings.

• St John's wort — Hypericum perforatum

  Toxin: Hypericin

  Photosensitisation — the compound reacts with sunlight and causes skin damage on unfeathered areas like the comb and wattles.

  Where you meet it: Rough grassland and borders. The effect needs both the plant and sustained sun exposure.

If a bird has eaten one

Remove whatever is left so the rest of the flock cannot get to it. Note which plant it was, how much, and roughly when — then phone a vet, and take a cutting or a photo with you. Identifying the plant with certainty is the single most useful thing you can hand over.

Do not try a home remedy first. With the fast-acting plants at the top of this page, the time spent guessing is exactly the time that mattered, and there is no household treatment that addresses a cardiac glycoside.

Frequently asked questions

Will chickens eat poisonous plants?

Usually not, if they have a choice. A flock with decent forage and full feeders tends to leave bitter, acrid plants alone, and most garden ornamentals taste unpleasant enough to be self-limiting. The exceptions are what matter: a bored flock confined with nothing else to strip, hedge clippings or bulbs tipped into the run, and birds turned onto bare ground where the toxic plant is the only green thing growing.

Which plants are most dangerous to chickens?

Yew is the one to know: it acts fast enough that birds are usually found dead rather than found ill, and clippings stay toxic after drying. Oleander, castor bean, water hemlock, foxglove, monkshood, lily of the valley, azalea and laburnum are in the same tier — a small amount can kill. There are 10 plants at that severity on this page.

Are hedge clippings safe to put in a chicken run?

Not by default, and this is the single most common route to a poisoning. Yew, privet, box, laburnum and rhododendron are all common hedging plants, and several of them stay toxic after the cuttings dry out. A flock will strip a fresh pile of greenery out of curiosity in a way it would never strip the living hedge. Compost clippings somewhere the birds cannot reach.

What should I do if my chicken eats a poisonous plant?

Remove whatever is left so the rest of the flock cannot get to it, note which plant it was and roughly how much and when, and phone a vet for advice. Take a cutting or a photo of the plant with you. Do not try a home remedy — with the fast-acting plants on this list, time spent guessing is the thing you cannot get back.

Is it safe to let chickens free-range in my garden?

For most gardens, yes, provided you know what is growing in it. Walk the space once and look for the severe-tier plants here, and fence those off or take them out. After that the realistic risks are seasonal: bulbs sitting on the surface at planting and lifting time, prunings left in a heap, and windfall fruit fermenting under a tree.

Do toxic plants make the eggs unsafe to eat?

For the plants on this page, the practical concern is the bird rather than the egg — a hen that has eaten enough yew or oleander to matter is the emergency. Some plants do change eggs in other ways: heavy flax feeding alters yolk fatty acids, and marigold and other carotenoid sources deepen yolk colour. Those are compositional changes, not safety ones.

Related

• What can chickens eat? A sourced verdict on 91 foods
• Can chickens eat avocado? — a garden plant that is also a never-feed
• Can chickens eat rhubarb? — a garden plant that is also a never-feed
• Can chickens eat grass clippings? — why mower cuttings are their own risk
• Chicken Treat Calculator — how much of the diet treats can be
• Coop Size Calculator — a run big enough that boredom stops being the problem