Is Wild Calla Poisonous? – Toxic to Humans & Animals

Yes. Wild calla is poisonous to humans, dogs, cats, and horses. All parts of the plant contain insoluble calcium oxalate crystals that cause immediate oral irritation when chewed. Most cases are mild and resolve fully with prompt treatment, but severe oral swelling can occur and documented kidney damage exists with certain species. Note: “wild calla” (Arum palestinum, also called Black Calla or Solomon’s Lily) is a different plant from the ornamental Calla Lily (Zantedeschia aethiopica); both are toxic but belong to separate genera.

Wild Calla vs. Calla Lily - Are They the Same?

No, but the confusion is understandable. Both are in the Araceae family and both contain calcium oxalate crystals, so the toxic mechanism and first-aid response are the same. The distinction matters for identification and regional context.

Ornamental Calla Lily: Zantedeschia aethiopica. Widely grown in gardens and as cut flowers. Toxic to dogs, cats, humans, and horses.

Wild Calla: Arum palestinum (also called Black Calla, Solomon’s Lily, Wild Arum). Less common, originally from the Middle East and Levant. Toxic to dogs, cats, humans, and horses.

Related species: Arum maculatum (cuckoopint, lords and ladies) found across Europe is more toxic than Arum palestinum. Its berries are especially concentrated with calcium oxalate crystals and have caused severe kidney damage and airway compromise in documented cases. European readers are more likely to encounter this species.

Both groups require the same immediate response if ingested. The key takeaway: any plant in the Arum genus should be treated as toxic.

What Makes Wild Calla Toxic?

Insoluble calcium oxalate crystals called raphides. These crystals are sharp and needle-like. When a person or animal chews the plant, the raphides penetrate oral tissue and cause immediate physical injury through microscopic cuts. This is a mechanical mechanism, not a chemical one. The crystals do not dissolve, which is why the irritation persists until the tissue heals.

The crystals are concentrated in the leaves, with lower amounts in stems and flowers. The berries of Arum maculatum carry a particularly high concentration, which is why children who ingest them are at greater risk.

This mechanism differs from soluble oxalates, which bind calcium in the bloodstream, and from toxins like grayanotoxins, which affect sodium channels.

Which Parts of Wild Calla Are Poisonous?

All parts: leaves, stems, flowers, roots, and berries. Casual contact with intact plant skin carries minimal risk. The toxin is released when the plant is chewed or crushed. Berries, especially those of Arum maculatum, are the most commonly ingested part by children due to their bright red-orange color and are particularly dangerous.

Symptoms of Wild Calla Poisoning

Onset is immediate. The calcium oxalate crystals cause symptoms within minutes of chewing.

Humans: Burning and irritation of mouth, tongue, and lips; excessive drooling; blisters in the mouth; nausea and vomiting; diarrhea; difficulty swallowing. Severe reactions (airway swelling, kidney effects) are rare but documented, particularly with Arum maculatum ingestion.

Dogs and cats: Pawing at the mouth; excessive drooling and foaming; oral inflammation and swelling; vomiting; difficulty swallowing; respiratory distress if swelling is severe. Most cases are mild with prompt treatment and full recovery is the norm.

Children: Same symptom profile as adults. Smaller body weight means proportionally greater risk at lower doses. Arum maculatum berries are the most common wild calla ingestion risk for children in Europe.

Horses: Grazing risk in paddocks where the plant grows. Oral irritation and gastrointestinal symptoms.

The prognosis for most exposures is excellent. Deaths are rare with appropriate care. Airway swelling is a real concern, however. It requires immediate medical attention.

What to Do If Wild Calla Is Ingested

1. Do NOT induce vomiting. Vomiting brings the calcium oxalate crystals back up through the esophagus and mouth, causing additional tissue damage.
2. Rinse the mouth gently with water if the person or animal is conscious and can swallow without choking.
3. Call US Poison Control (humans): 1-800-222-1222, available 24 hours a day.
4. Call ASPCA Animal Poison Control (pets): 888-426-4435, or Pet Poison Helpline: 855-764-7661.
5. Go to the nearest emergency vet or ER if there is any airway swelling, breathing difficulty, repeated vomiting, or if the animal or person is deteriorating.
6. Bring a photo or plant sample if you can do so safely. Accurate identification helps medical professionals triage treatment.

Preventing Wild Calla Poisoning

• Keep ornamental calla lilies and wild arum plants elevated or behind barriers so pets and children cannot reach them.
• For outdoor plants in pet-accessible yards, consider removal or fenced exclusion. Remove the plant if your dog or child has access.
• Teach children not to put plant parts in their mouths, especially berries.
• Wear gloves when pruning or handling any Arum species. Wash hands thoroughly afterward.
• If you forage or garden in areas where Arum maculatum grows, learn to distinguish it from non-toxic look-alikes. When in doubt, leave the plant alone.

Frequently Asked Questions

Is wild calla the same as a calla lily? No. They are different genera. Arum palestinum (wild calla) is different from Zantedeschia aethiopica (calla lily). Both are toxic and share the same toxic mechanism and first-aid response.

Can wild calla kill a dog or cat? Death is rare with prompt treatment. Most cases are mild and resolve fully. Severe swelling is the primary concern. Seek veterinary care immediately.

What does wild calla look like? Arum palestinum features a deep purple-maroon spathe. Arum maculatum (cuckoopint) has a green spathe and produces distinctive red-orange berries in late summer. Both grow in shaded woodland areas.

I found red berries on a wild plant. Could it be wild calla? Possibly. Arum maculatum produces red-orange berries and is common across Europe. Treat any unknown wild berry as potentially toxic and keep children and pets away.

Can I grow wild calla safely if I have pets? Only if the plant is completely out of reach. Even then, the risk of accidental ingestion is significant. If you have curious pets or young children, remove the plant.

What should I do if my child ate a berry from a wild arum plant? Do not induce vomiting. Rinse the mouth with water if your child can swallow. Call poison control (1-800-222-1222) immediately. Go to the ER if there is any mouth swelling, breathing difficulty, or vomiting. Bring a photo of the plant if possible.

Are Arum maculatum berries more dangerous than the leaves? Yes. The berries carry a very high concentration of calcium oxalate crystals. They are the most dangerous part of the plant, particularly for children, who are most likely to eat them because they look like something edible.