Are the leaves of lords-and-ladies poisonous? A comprehensive guide

September 21, 2025 •

4 min read

According to the ASPCA, lords-and-ladies ($Arum$ $maculatum$) is toxic to many animals, and the same toxic principles apply to humans. The leaves of lords-and-ladies are indeed poisonous, containing sharp, needle-shaped crystals that cause severe irritation. Understanding this plant's dangers is crucial for maintaining a safe home and garden.

Quick Summary

All parts of the lords-and-ladies plant are highly poisonous due to the presence of insoluble calcium oxalate crystals. Ingestion or contact with the plant can lead to immediate and intense burning and swelling of the mouth and throat, as well as severe skin irritation. Knowing how to identify and safely manage this plant is vital for protecting children and pets.

Key Points

Extremely Toxic: All parts of the lords-and-ladies plant, including its leaves, are poisonous to humans and pets.
Calcium Oxalate Crystals: The plant's toxicity is due to needle-like calcium oxalate crystals that cause severe pain and irritation upon contact or ingestion.
Immediate Symptoms: Ingestion causes immediate, intense burning, swelling, and numbness of the mouth and throat.
Contact Dermatitis: Touching the plant's sap can cause a burning, itchy rash on the skin.
Attractive Berries: The bright red berries appearing in autumn are particularly attractive and dangerous to children and animals.
Safe Handling is Key: Always wear gloves and dispose of all plant parts properly to prevent exposure and spread.

The Toxic Culprit: Calcium Oxalate Crystals

The primary reason for the plant's toxicity is the presence of insoluble calcium oxalate crystals, known as raphides. These needle-shaped structures are found in all parts of the lords-and-ladies plant, including its distinctive arrow-shaped leaves. When the plant is chewed or crushed, these crystals are released, puncturing the delicate tissues of the mouth, throat, and digestive tract. This mechanical irritation triggers an immediate and intense burning sensation, swelling, and pain.

Symptoms of Lords-and-Ladies Poisoning in Humans

Ingestion of any part of the lords-and-ladies plant can produce severe and immediate symptoms. Because of the instant pain, large amounts are rarely consumed, but even a small amount can cause significant distress. Symptoms can include:

Immediate, intense burning and stinging of the mouth, tongue, and throat.
Numbness or tingling sensation in the affected areas.
Excessive drooling.
Swelling of the lips, tongue, and throat, which in severe cases can cause difficulty breathing or swallowing.
Nausea, vomiting, and stomach pain.

Skin contact with the plant's sap can also cause contact dermatitis, leading to an itchy, burning rash.

Symptoms in Pets

Lords-and-ladies is also highly toxic to many animals, including dogs, cats, and horses. Pets may exhibit similar signs of oral irritation, including:

Excessive drooling or foaming at the mouth.
Vomiting.
Difficulty swallowing.
Paw-ing at the mouth.
Oral swelling, which may lead to breathing difficulties.

Most animals will quickly stop chewing after the first bite due to the immediate pain, which often prevents more serious harm. However, a veterinary visit is always recommended after any suspected ingestion.

Identifying Lords-and-Ladies ($Arum$ $maculatum$)

To ensure your safety and that of your family and pets, it's essential to be able to identify this plant. Key features include:

Leaves: Large, glossy, dark green, and arrow- or spearhead-shaped, sometimes with purple-black blotches.
Flowers: Appear in spring. A creamy-white or pale green, hood-like sheath (spathe) surrounds a central, club-shaped spike (spadix).
Berries: In late summer and autumn, the leaves die back, leaving a distinctive cluster of bright orange-red berries on a stalk. These berries are particularly attractive and highly poisonous.

Comparison with Harmless Plants

It is sometimes confused with other plants. Here is a table comparing lords-and-ladies with a harmless lookalike, Common Sorrel ($Rumex$ $acetosa$), which can grow in similar habitats.


Feature	Lords-and-Ladies ($Arum$ $maculatum$)	Common Sorrel ($Rumex$ $acetosa$)
Leaves	Arrow-shaped with rounded 'tails' at the base. Glossy, waxy texture. May have dark blotches.	Arrow-shaped with pointed 'tails' at the base. Not glossy or waxy.
Habitat	Prefers damp, shady woodlands and hedgerows.	Common in open fields, meadows, and grasslands.
Flowers	Distinctive spathe and spadix.	Small green or reddish flowers on a tall, slender stalk.
Berries	Cluster of bright orange-red berries.	No berries; seeds are small and brownish.
Toxicity	Highly toxic.	Edible when prepared correctly; non-toxic.

Safety and Prevention Measures

Wear Protective Gear: Always wear gloves and long sleeves when handling lords-and-ladies to prevent skin irritation from the sap.
Remove with Care: When removing the plant from your garden, dig deep to ensure all tubers and roots are removed. Any leftover pieces can resprout.
Proper Disposal: All parts of the plant, including leaves, roots, and berries, should be double-bagged and disposed of in the trash, not composted.
Child and Pet Supervision: Keep a close eye on children and pets in areas where lords-and-ladies grows, especially during late summer and autumn when the attractive berries are present.
Educate Others: Make sure family members, especially children, can identify the plant and know not to touch or eat any part of it.

What to Do in Case of Exposure

If ingestion or significant skin/eye contact occurs, immediate action is necessary:

Ingestion: Give the person or pet cold drinks or ice cream to help numb the area and flush the mouth. Do not induce vomiting. Call a poison control center immediately for further guidance.
Skin Contact: Wash the affected area with soap and continuous running water for 10-15 minutes.
Eye Contact: Irrigate the eye with lukewarm running water at low pressure for 10-15 minutes, keeping the eye open during the process.

For more detailed information on plant toxicity in animals, consult a trusted resource like the ASPCA: ASPCA Toxic and Non-Toxic Plant List.

Conclusion

The question, "Are the leaves of lords-and-ladies poisonous?" has a definitive answer: yes, they are, along with every other part of the plant. The dangerous, needle-like calcium oxalate crystals are a serious health hazard upon contact or ingestion. While the immediate irritation often prevents large quantities from being consumed, the risk to children and pets is very real. By learning to identify lords-and-ladies, practicing safe handling and removal, and knowing the proper steps in case of exposure, you can effectively mitigate the risks posed by this deceptive plant.

Frequently Asked Questions

If a pet ingests the leaves of lords-and-ladies, it will likely experience immediate oral pain, causing it to drool excessively, paw at its mouth, and vomit. While large ingestions are rare due to the initial pain, you should contact a veterinarian immediately for guidance.

Yes, lords-and-ladies ($Arum$ $maculatum$) can be confused with other plants. For instance, its leaves can look similar to the edible Common Sorrel, but sorrel has pointed 'tails' on its leaves, while lords-and-ladies' are rounded.

Yes, the bright orange-red berries that appear in autumn are also highly poisonous and can be particularly tempting to young children.

To remove lords-and-ladies, wear protective gloves and dig deep to extract all tubers and roots. Dispose of all plant parts in the trash, not your compost pile. For persistent infestations, you may need to sift the soil or use a weed mat.

Lords-and-ladies leaves are typically large, arrow-shaped, and glossy. Some may also have distinctive purple or black blotches.

If your skin comes into contact with the sap, you should immediately wash the area thoroughly with soap and running water for 10 to 15 minutes. Contact with the sap can cause a burning, itchy rash.

Yes, all parts of the plant, including the leaves, stems, roots (tubers), flowers, and berries, contain the toxic calcium oxalate crystals.