Giant hogweed

What is giant hogweed?

Giant hogweed (Heracleum mantegazzianum) is a herbaceous plant from the umbelliferous family that originally comes from the Caucasus. It was introduced to Europe as an ornamental plant in the 19th century and has spread rapidly since then. It grows mainly in damp places such as riverbanks, ditches or forest edges and can grow up to five meters high.

The plant has a thick, hollow stem with red spots and large, serrated leaves. The flowers are white and form large umbels with a diameter of up to 40 centimeters. The flowering period is from June to August.

Why is giant hogweed dangerous for dogs?

Giant hogweed contains toxic substances called furanocoumarins in all parts of the plant. These act as a contact poison, i.e. they trigger a reaction when they come into contact with the skin and sunlight. The furanocoumarins make the skin sensitive to light and cause burns that can resemble sunburn.

The symptoms can vary depending on the severity, but redness, swelling, blisters or ulcers on the affected areas are typical. These are usually the dog's muzzle or head, as it comes into contact with the plant when sniffing or nibbling. The skin lesions can be very painful and lead to scarring or hair loss.

In addition to skin problems, giant hogweed can also cause other symptoms such as eye irritation, breathing difficulties or gastrointestinal disorders. In rare cases, it can even lead to allergic shock or kidney failure.

How can you protect your dog from giant hogweed?

The best prevention is, of course, to avoid contact with giant hogweed. To do this, you should know the plant well and be able to recognize it. It is similar to the harmless meadow hogweed (Heracleum sphondylium), which is also found in Germany. The main difference lies in its size: while meadow hogweed usually grows no taller than 1.5 meters, giant hogweed can reach more than three times that height.

Giant hogweed also has red spots on the stem and larger leaves and flowers than meadow hogweed. If you are unsure whether it is giant hogweed or meadow hogweed, it is better to play it safe and keep your dog away from the plant.

When you take your dog for a walk, you should make sure that he does not sniff or chew on giant hogweed. It's best to keep him on a lead or call him off if he shows an interest in the plant. Also avoid touching or breaking off the plant yourself, as you can also burn yourself.

What can you do if your dog has touched giant hogweed?

If your dog does come into contact with giant hogweed, you should act quickly to mitigate the consequences. The most important thing is to rinse the affected areas of skin immediately with plenty of water to remove the sap. It is best to use gloves or a cloth to protect yourself.

Then take your dog into the shade or indoors as quickly as possible to protect it from further exposure to the sun. The skin reaction can only occur after a few hours and can be exacerbated by light. Keep a close eye on your dog and consult a vet at the first sign of skin changes or other symptoms.

The vet can treat the skin lesions and prescribe painkillers or antibiotics if necessary. They can also give you tips on how to support wound healing and prevent infections. Burns usually heal within a few weeks, but there may be permanent damage such as scars or hair loss.