Now here is a fascinating twist on the same old story.  We find a noxious weed running rampant across our landscape, doing its evil and “blah, blah, blah" — but lo — it is not all bad.

Meet the bad Japanese knotweed (Polygonum cuspidatum). This beast of a weed has a playbook full of dirty tricks: running, re-propagating rhizomes; wide soil and salt tolerance; no pests or diseases; canes and leaves that grow fast and tall to crowd out native plants.

“But wait!” Meet the good Japanese knotweed. This beauty of a weed may also have a good heart: powerful, “age-reversing” anti-oxidants; resistance to some cancers; protection against heart disease and diabetes; cholesterol reducing properties; Alzheimer plaque-blocking properties.

So what’s the real story?

Knotweed has a human history more subtle and complex than “weed.”  It begins back in its native land, where Hu Zhang is the epithet for powdered knotweed root in traditional Chinese herbals. For centuries, it has been prescribed as an analgesic, diuretic and expectorant, to treat bronchitis, jaundice, and hypertension. Western medicine has recently isolated and identified a powerful antioxidant from the entire plant as the probable active ingredient in knotweed. This fairly small, 14-carbon organic molecule has no common name, so we’re stuck with “trans-resveratrol.”  But I am going to practice pronouncing it, because it’s the same heart-healthy stuff found in red wine at the crux of the French Paradox, but at 80 times the concentration.

Knotweed synthesizes trans-resveratrol as a sort of botanical immune response to fungal and bacterial pathogens, even making larger quantities in moldy springs.  The chemical apparently acts to absorb harmful free radicals released during knotweed’s argument with pathogens.  This is why trans-resveratrol intrigues us moderns, for it displays substantive ability which hints that it may transfer well to the realm of human health and disease.  Its appeal leaps beyond fringe healing to find interest amongst some of the best minds practicing conventional medicine.

Current knotweed research is probing trans-resveratrol’s capacity to interrupt free-radical cascades in the electron transport transport chain of cell metabolism, to block carcinogenesis, to interfere with plasma LDL and its role in atherosclerosis, and to indirectly activate our sirtuin genes and so mimic the inhibitory effect of caloric restriction on aging. And that’s just some of it. Phew.

Here is where the story leads us to Cleveland Botanical Garden. Lately, we can find the asparagus-like shoots of Japanese knotweed bunched at our market stands, for sale as a tonic comestible.  And since last September, the Garden and I have been providing modest technical assistance to Lynne Thompson of Ohio Magazine, to forward her research for an April, 2010 article exploring knotweed as a constituent of a healthy cuisine (www.ohiomagazine.com/Main/Articles/Asian_Invasion_4153.aspx).  It is a good article; good work, Lynne.

“Technical assistance” has amounted to me attempting to grow some knotweed indoors to produce an out-of-season winter shoot crop.  Lynne wanted to bake a knotweed pie!  So, being a hungry man, I wild-collected seeds and rhizomes, and potted both in our working glasshouse.  But this was to little avail, for both propagules (hi-falutin’ word for germinate-able tissue, be it seed or shoot or root) were already locked into their seasonal dormancy cycle.  The seeds simply sat. The rhizomes sent up weak sprouts and leaves, which lingered but did not grow in manifest until February.

No pie. Lynne’s article went to press, complete with a tantalizing description of knotweed pie, but still, no pie. Being a determined girl, Lynne convinced me to nevertheless help her see this project through, go out this spring and harvest a pie-worthy mess of knotweed.  After I agreed to round two, she cleverly added, “and do you know where we can find some of the stuff?”  Deciding my continuing promise of pie was worth this new effort, I quizzed the Garden Green Corps staff, who just happened to have some knotweed growing on their Fairfax Urban Learning Farm (http://www.cbgarden.org/Green_Corps/Learning_Gardens.html).  For a small inferred bribe involving chocolate or alcoholic beverage, I was soon granted privilege to escort Lynne there on a harvesting expedition.

Knotweed season is well upon us, so after a flurry of phone tag, we hurriedly set last Friday morning for the big harvest.

Lynne brought along a surprise guest.  “Hi, I’m Mike,” was his unpretentious-as-a-howdy greeting for me.  It took Lynne to explain that it was “Mike” as in “Dr. Michael Roizen,” director of wellness programs for the Cleveland Clinic Foundation.  If serendipity was my sensation at shaking hands with this man whose wellness books are dog-eared on my library pile (this handshake alone makes me 1.3 years younger), I was also unsurprised that he was curious to see knotweed in situ.

The harvest went without incident, aside from giving me the pleasure of watching two informed and intelligent people express such optimism for this weed that mostly causes me and my peers to hyperventilate. It was refreshing and instructive.  Seeing them with their open eyes has prompted me to ponder anew the ecological/social dialectic between weeds and people.  Without trying to put too-fine a point on it, it has given me intent to see weeds not as the enemy, not as bad or good, but simply as living things put out of place. If we have made knotweed into a weed with a capital W, it seems to me that it would be a second slip to destroy it with no consideration for its unknown potential.

Trans-resveratrol may not prove to be the fountain of youth that we hope it to be, but the lesson is still true.  Knotweed, having interacted with us for generations across continents and societies, teaches me about us as much as about itself. 

And to me, that’s the real story.  Knotweed isn’t so easy to loathe, after all.  We need to control this weed, and we especially need to control ourselves.  Villain and healer wearing one mask, I look at Japanese knotweed and see myself in the mirror.

It was nice to meet ya, Mike.  And if you see Lynne, please tell her I’m still waiting for my knotweed pie.

Posted by Mark Bir

Do you have a vegetable garden? Is this your first year with one? The National Gardening Association expects a 19% increase in the number of edible gardens installed in the US this year. The economy is one of the driving forces behind this uptick. When the going gets tough, the tough get gardening! I personally grew up with a huge vegetable garden full of peppers, tomatoes, rhubarb (ew), and lots of weeds. My job was to remove said weeds. I think this task scarred me – thanks Dad  – because of the HUGE spiders I always encountered. I was little and I think the spiders were car-sized. I still completely lose it when I see one. But let’s move on; I’ve digressed and I’m freaking myself out. Why all the vegetable gardens? Why are we composting, shopping at the ever-increasing number of farmer’s markets, and starting plants from seed – from seed! Why does it matter? Does it even matter? If you ask Will Allen – founder and CEO of Growing Power in Milwaukee – it does matter, and it’s a matter of life and death. He became alarmed at the increasing rates of obesity and diabetes, particularly in low-income families with limited or no access to fresh fruits and vegetables. The closest place to shop for these families may be a convenience store a mile away with over-salted, over-sugared, over-processed “food." Growing Power was founded to bring fresh greens, fruits, and veggies to inner-city dwellers and now provides them to over 10,000 people a year. 

Will Allen, who was just featured in a major article in the New York Times Magazine last Sunday, is coming to Cleveland. He is the keynote speaker at the American Horticultural Society’s National Children & Youth Garden Symposium, hosted by Cleveland Botanical Garden. I am SO excited to meet him; I’m starting to lose sleep. We are taking him to several of our Learning Gardens to see our urban farms, meet Green Corps staff, and most importantly, meet some of the students we employ to work these acres. I’m not sure our teens realize who it is they are meeting in just 2 weeks, or the impact he has had in Milwaukee and many other cities. But I think Mr. Allen will be impressed with what he sees happening at our Learning Gardens. Yes, we have some weeds – I’m not going to pull them, Dad –however, I think he will enjoy experiencing the “fruits” of their labors this summer.