Celebrating the Wild Side of Yorkshire’s Coast & Country: The march of the Giant Hogweed

Celebrating the Wild Side of Yorkshire’s Coast & Country:

The march of the Giant Hogweed

Massive Giant Hogweed Flowerhead by Ian Rotherham

The massive flower-head of Giant Hogweed

One local writer on the Peak District suggested that ‘……contenders for the Peak’s most loathed plants are Japanese Knotweed, a highly-invasive species that is difficult to control, and Giant Hogweed, a Triffid-like plant of gargantuan proportions which shades out everything in its path.’ However, for the Victorian ‘Wild Gardeners’ inspired by William Robinson, the Giant Hogweed (Heracleum mantegazzianum) was one of a suite of species used to make ‘wild’ gardens and parks across the country. Robinson stated that the principle of wild gardening was ‘…..naturalizing or making wild innumerable beautiful natives of many regions of the earth in our woods, wild and semi-wild places, rougher parts of pleasure grounds, etc’. He goes on to suggest that it is ‘…..very suitable for rough places on the banks of rivers or artificial water, islands, or any place where bold foliage may be desired’.  However, he notes that ‘….when established they often sow themselves so that seedling plants in abundance may be picked up around them; but it is important not to allow them to become giant weeds’. Writing in the 1870s, if only he had known what was to follow.

Giant Hogweed was introduced from the Caucasus sometime in the early 1800s. Certainly, by 1849, it was being sold commercially by nurseries. Nevertheless, it was not until the 1970s, that the real scale of the invasion, and the potentially serious consequences, were recognised. The plant has spread far and wide, and I have been monitoring its invasion of our region since finding it in 1976 on the Boating Lake at Graves Park. Despite a major control effort a decade or so ago, it is still there, and has now spread downstream. A big infestation took place about ten years back on the River Sheaf near Heeley Baths and after some strong lobbying and hints of legal actions, the riparian owners took action and for a while the plant was controlled but not eradicated. In the last two years it has bounced back, and with winter and summertime floods of the last few years, the entire catchment downstream must now be considered contaminated. Bear in mind that each plant produces around 5,000 highly viable seeds and these easily float in water, and you can see the potential for spread.

GH2

At Salmon Pastures on the River Don, courtesy of SPRITE and Ant Graham

The problem with this notifiable weed is not merely its impact on native fauna and flora, but that its coarse and prickly hairs, on the leaves and on the stems, can cause lacerations and these react to the poisonous sap of the plant. Furthermore, the rash that results can be photosensitised, lead to permanent tissue damage, and cause scarring. Kids love to play in the jungle-like stands of Knotweed and the stems make great blowpipes, so this is a serious worry for parents.

Common hogweed  by Ian Rotherham

Common Hogweed

Hogweed is a seriously big plant and really, there is no mistaking its stature and the massive leaves borne on huge, coarsely hairy stems. Generally, if you think you have found Giant Hogweed but are not sure, then you have Common Hogweed (Heracleum sphondylium) , which can be quite big. If you have mantegazzianum, then you will surely know it. This stunning plant is also embedded in our popular culture. As far as I know, it is the only invasive, alien species immortalised in a rock ballad, in this case, the 1970s Genesis LP Nursery Cryme.

 The Return Of The Giant Hogweed

Turn and run,

Nothing can stop them,
Around every river and canal their power is growing.
Stamp them out,
We must destroy them.
They infiltrate each city with their thick dark warning odour.

Still they’re invincible,
Still they’re immune to all our herbicidal battering.

Long ago in the Russian hills,
A Victorian explorer found the regal Hogweed by a marsh,
He captured it and brought it home.
Botanical creature stirs, seeking revenge.
Royal beast did not forget.
He came home to London,
And made a present of the Hogweed to the Royal Gardens at Kew.

Waste no time,
They are approaching.
Hurry now, we must protect ourselves and find some shelter
Strike by night
They are defenceless.
They all need the sun to photosensitize their venom.

Still they’re invincible,
Still they’re immune to all our herbicidal battering.

Fashionable country gentlemen had some cultivated wild gardens,
In which they innocently planted the Giant Hogweed throughout the land.
Botanical creature stirs, seeking revenge.
Royal beast did not forget.
Soon they escaped, spreading their seed, preparing for an onslaught,
threatening the human race.

The Dance of the Giant Hogweed

Mighty Hogweed is avenged.
Human bodies soon will know our anger.
Kill them with your Hogweed hairs
HERACLEUM MANTEGAZZIANI

Giant Hogweed lives.

GH3

At Salmon Pastures on the River Don, courtesy of SPRITE and Ant Graham

Well we are now trying to gather more up-to-date information on where the plant occurs and where it is spreading. Led by SPRITE (The Sheffield Partnership for Rivers in the Town Environment), there are now attempts to control the worst outbreaks along the Rivers Don and Sheaf. Let us know if you see it, and if you are not sure, then email me a picture, but do not touch the plant without protective clothing.

Ian D. Rotherham, Writer, Broadcaster, Professor of Environmental Geography, Reader in Tourism & Environmental Change

All these are Giant Hogweed except the top middle -which is a rather puny Common Hogweed!! Some pictures of leaves to follow.  

GH1Umbellifer Common Hogweed P1530936 P1530940 P1530956

This entry was posted in Latest News. Bookmark the permalink.

One Response to Celebrating the Wild Side of Yorkshire’s Coast & Country: The march of the Giant Hogweed

  1. Lee Swords says:

    I think that there is some on Car Brook Ravine…I know there is some behind the fishing lakes at Shireoaks

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s