Invasive species: Knotweed - Reply to Mr. Rice updated

In reply to Mr. Rice’s comments which I posted under the heading More Invasive Musings, May 25, 2007,, I should like to address each of his points.

I don't get your point about your nursery selling Japanese knotweed to a customer who was then angry that it took over her garden.
Neither do I.
It would seem that I unintendedly committed elision from the collision of two vaguely related ideas. Your point is well taken. I should have dealt with the name change separately and simply discussed the implications of sales of known or unknown invasives.


Although it's unfortunate that Japanese knotweed has had a number of botanical names over the decades it's not exactly news that it's name is now settled at Fallopia japonica.
I thought the taxonomists had moved on, and according to the National Invasive Species Center, the current name would be Polygonum cuspidatum Siebold & Zucc. This of course makes no difference to my efforts in reporting the story or to Mr. Rice's points.

From the Japanese Knotweed Alliance:

"Nomenclature
Japanese knotweed belongs to the plant family Polygonaceae, the knotweeds. ‘Poly’ meaning many, ‘gony’ from the Greek ‘knee’ meaning jointed.
An artefact of the history of discovery of this plant is that it has three scientific names:Reynoutria japonica - described from Japan by the Dutch botanist Houttuyn in 1777, the name was lost for 125 years.Polygonum cuspidatum - independent description by Siebold and Zuchharini in 1845. Fallopia japonica - a result of the amalgamation of Reynoutria and Fallopia resulting in the oldest name being used.
The scientific name of Japanese knotweed in current use is Fallopia japonica. Previous scientific names also include Polygonum sieboldii, Polygonum japonicum, Polygonum zuccharini Small, Pleuropterus zuccarinii, Polygonum reynoutria (in USA horticulture trade).
In Japan, the plant is commonly called itadori (meaning 'take away pain'). In its introduced range, common names include Japanese knotweed, Sally rhubarb, donkey rhubarb, gypsy rhubarb, Hancock's curse, Pysen saethwr, Glúineach bhiorach, Mexican bamboo, Japanese bamboo, Japanese fleece-flower, wild rhubarb and crimson beauty. "

Without a doubt I seem to be behind the times on knoweed's nomenclature, though this is a case of writing without proofing; as Jenn from Invasivespecies, points out, Mr. Rice is, of course, correct. Mostlikely explains this whole situation: one of catching up from a thousand year tradition of modifying or negating "nature".


And can't the nursery staff recognize Japanese knotweed when they see it?
Currently they would not see it because we no longer sell it,. The point I so ineloquently failed to make was that at the time of sale in the 1990’s, “new” was the market norm, and “new” is what the public wanted, and “new” is what we focused on. So the sales staff at that point in time would have rang the bells about the plants ”newness".

And who put it in a pot and gave it a tag in the first place?
Back in the 90’s we grew most of our perennials from cutting or divisions, so the answer is: I did.

Your propagator? A wholesale grower?
I did

So a new plant arrives... does no one bother to find out anything about it?
Actually we spent a great deal of time finding landscape uses for this plant and extolling the design potential. The 300 year tradition of landscape design in the United States, firmly rooted in European grand garden traditions did not include a section on invasive. In fact, the gardening tradition we operated in called for the removal of natural areas around our houses and home and the replanting with artificial controlled designs based on centruy old gradening traditions and methods.

Sorry, but the nursery is 100% to blame.
In today’s market, I operate under a policy of information sharing with my customers so that together we will make the right decisions. Changing rules and changing ideas based on changing science, allows us to judge in hindsight. Fair enough.



I am extremely skeptical(sic) about much of the hysteria surrounding invasives, but any nursery selling Japanese knotweed, even the variegated form, should take full responsibility for the consequences.
I agree. With the amount of information readily available, a seller is taking responsibility. Thus when it took over our entrance way in the late 1990’s, we stopped selling because of our own empirical data.. Today one can go on line and read for many hours about the challenges to natural areas this plant causes.

So what did the nursery do for the customer?
Hearing the story, I shared eradication notes with the customer. I am sure that this does not meet expectations where customers have no responsibility and all must afll to the seller. I think that a sale is a two way proposition requiring one to remeber "caveat emptor" to a small extent. When the knotweed was sold, we sold it as a "new" and exciting pklant to add to a home opr commercial landscape. We kept our word based on the information at the time. But life goes on, and because of new ideas and information the policy changed. I explained the change in our/my understanding of the interactions between natural areas and our landscapes and the work we do to educate our customers. We have unilaterally stopped selling Lythrum over 12 years ago. The loss of sales approaches $500,000, but the gain to the environment and our long term quality of life is immeasurable. We also have discontinued Bradford pears, many varieties of Miscanthus, and many common vines which were popular in the early 90’s such as porcelain berry.