Japanese Knotweed Solutions Ltd. Blog "Growing Concerns"

How and Why...?

April 24th 2015

If I had a pound for every time certain questions were asked I would be a rich man...! One of my favourite questions has to be ... ‘...and what is it that you do?’ – this question is regularly asked to Mike Clough of ... ‘Japanese Knotweed Solutions’ ...the clues in the name guys!

One of my other favourites is when people ask ... '...and where does it come from?’ ...duuuh... ‘Japanese Knotweed’ surprisingly comes from ...wait for it...JAPAN!

In all honesty - it’s a little more complicated – Japanese Knotweed is actually native to China, Taiwan and the Korean peninsula as well as Japan, so could just as easily have been called Chinese Knotweed, Taiwanese Knotweed or even Korean Knotweed...!

It is however pretty much accepted that its date of introduction to Europe was 1849 from the nursery of Philip von Siebold who then sent it to the Royal Botanical Gardens at Kew in 1850 (Conolly 1977).

Fallopia Japonica was then made available to the general plant buying public in the same year...and advertised as hardy, quick growing, tolerant of a variety of conditions and useful as a fodder crop for your horses and cattle. Fallopia Japonica was also sent to the Royal Botanical Gardens at Edinburgh in 1854 where it was then further distributed across the UK and most likely to the USA as well.

By the late 1880’s the plant had become ‘naturalised’ and was reported growing on cinder tips near Glamorgan South Wales and on patches of cultivated ground in Oldham, Lancashire.

Gardeners being the type of people that they are - love to celebrate the success of a plant that they have used, by offering cuttings to their friends and neighbours and have inadvertently massively expanded the growth range of Japanese Knotweed. The Victorians loved their ‘wild gardens’ where they re-created ‘natural’ landscapes by having quick growing Japanese Knotweed planted as a ‘back drop’ to their more exotic garden plants.

Quick growing Fallopia Japonica was also used to hide the toilet at the bottom of the garden (leading to it being called the ‘outhouse plant’ in the USA). It was often intentionally introduced as an ornamental and by the 1900’s the number of naturalizations increased rapidly. Introduction and spread in other European Countries followed a very similar pattern as that in the UK.

When one looks at the list of countries that introduced Japanese Knotweed and now have a problem with it being ‘invasive’ the list is never ending:

Austria                  introduced                          invasive

Belgium                introduced                          invasive

Czech Republic    introduced                         invasive

France                  introduced                         invasive

Germany              introduced                          invasive

Ireland                  introduced                         invasive

Netherlands         introduced                         invasive

Norway

Poland

Spain

UK

Australia

New Zealand

Etc etc etc

You would think that along the way ...somebody would have twigged that maybe this plant wasn’t such a great idea?

So the answer to ‘how?’ is detailed above, the answer to ‘why?’...would be

... ON PURPOSE!

 

Mike C