The Hokkaido University campus in Sapporo recently had a brand new visitor in the form of a gigantic and highly toxic plant. It’s called the giant hogweed and its name is no exaggeration as the ones found were identified by their height of around three meters.

The giant hogweed can get even taller, up to around five meters, and has a rather innocuous weed-like appearance that belies the dangers that lurk within it. The plant’s sap contains a phototoxic substance that, when in contact with the skin and exposed to sunlight, causes severe swelling and blistering.

▼ News report on the discovered giant hogweed

Hokkaido University quickly cordoned off the area and cut down the plants, but the unexpected presence of them could suggest that there’s giant hogweed elsewhere in Sapporo or even in other parts of Japan. It’s unclear how the plants got to the campus in the first place but an expert suggested that seeds may have been accidentally carried on someone’s shoes or clothing.

News reports have been calling the giant hogweed “one of the most dangerous plants in the world” and if you google “most dangerous plants in the world” it actually does appear among hemlock and nightshade in the top nine. However, it’s not known to be lethal, with the worst effect being temporary blindness if the sap gets in your eyes and is activated by UV rays.

The other good news is that giant hogweed is only dangerous when the sap is touched. Its phototoxins cannot be spread any other way, such as over the wind, but nevertheless, the effects of touching it are about as unpleasant as it gets.

If you happen to come into contact with it, wash the area as soon as possible, doing so carefully to avoid spreading it to other parts of your skin. Also, handle clothing carefully while cleaning it. If skin irritation does occur it can be alleviated with topical steroids, but for the most part you’ll just have to wait it out for a few days. Affected areas will also be extra sensitive to sunlight possibly for years after exposure, so sunblock or long sleeves may be needed, even if it does draw the attention of the police.

You’re better off preventing it from ever happening by keeping your eyes peeled for plants that look like the giant hogweed and reporting them to your local authorities as soon as possible so they can dispose of them safely. There is a good chance it might just be a less hazardous hogweed species, but better safe than blistery.

Read more stories from SoraNews24.

-- Beautiful forest-style Studio Ghibli specialty shop reopens at Tokyo Skytree this summer

-- A nearly 400-year-old Kyoto temple ordinarily closed to public is accepting visitors this summer

-- World’s first “transparent paper cup” developed in Japan