Giant Hogweed | Friend or Foe?

Not all plants live up to their name sake, but in the case of Giant Hogweed Heracleum mantegazzianum it really does. Standing up to 4 metres tall this giant among wild flowers is really quite a sight to behold - one that once you've witnessed you will not likely forget.

Looking at pictures and trying to tell the difference between similar species of Hogweed or any umbellifer (plants with umbrella-like white flowers) is quite a tricky task, but there is NO mistaking the Giant Hogweed once it's fully grown - it dwarfs it's relations and looks more like something out of the backdrop of a prehistoric film set than that of a commonly found plant.

Whilst Giant Hogweed is usually referred to as Heracleum mantegazzianum in the UK, there are actually several species that can be found growing in the UK and all of them contain furanocoumarins – a chemical that once on the skin causes burning by making the skin very sensitive to sunlight.

Other than it being very invasive, if left alone, Giant Hogweed will cause you no problems at all. It is when the plant is damaged that the issues start. Contained within the tree branch-like stems are high levels of furanocoumarins – which, 9 times out of 10 are exposed to humans whilst using strimmers – sending the sap spraying all over the place and causing nasty reactions when coming into contact with the skin. Another common cause of burning (in the past) was from children making blowpipes from the hollow stalks. The hairs on the leaves and stems may also cause some bad reactions, so it’s a plant that is best admired from a far rather than close up and personal.

So where did Giant Hogweed come from? Giant Hogweed is a native of Southern Russia and Georgia, but was introduced to Great Britain in by way of the Royal Botanic Gardens Kew – it was added to their Seed List of 1817 where it was to be grown as an ornamental species. Of course, with the best laid plans, the plant since escaped and began to colonise the countryside shortly after, first being recorded in Cambridgeshire, but it has spread ever since and continues to do so.

One particular reason that bushcrafters should learn to identify the Giant Hogweed is because of its resemblance of Common Hogweed Heracleum sphondylium, which is frequently used in cooking as a hedgerow snack.

Common Hogweed Heracleum sphondylium is sturdy plant. It was originally used as pigs fodder - hence the name “hogweed”. This smaller Hogweed still grows to a large size – somewhere around 6ft, but nowhere near as tall or bulky as its giant cousin (once fully grown). The leaves of common hogweed are far less severely toothed.

I’ve not intended this article to be an ID guide, hence the lack of identification tips.

What are your experiences with Giant Hogweed? Do you have burns from Giant Hogweed, or maybe it’s growing in your garden and you’re unsure what to do with it? Share your comments and stories below.