How to handle overgrown Poison Ivy, Kudzu, Thistle, Bamboo & other "Steel Cage Weeds"
(as seen in his weekly column in the Philadelphia Daily News)

Q. The bank at the end of our yard is invaded with either Japanese knotweed or kudzu. The underground roots are impossible to remove--thick and hard as tree limbs. I tried all kinds of herbicides; no luck. I mulched with plastic weed mat and stones; it pushes right through. HELP!
---Happy listener Charlotte Martin; Merion PA

Mike, would vinegar get rid of bamboo? Years ago, a neighbor dumped some next door. Subsequent owners attacked it vigorously, forcing it to the path of least resistance--our yard. Please make me a hero to my wife--help me get rid of it!
---Alan Kreisher

...the thistle are taking over!
---Carl~~~~

...a large mass of poison ivy in my backyard, bordering a corn field....
---Debbie Craig, East Greenville PA

A. Charlotte: From the size of the roots and location, it's likely the notorious kudzu (Pueraria lobata), planted there years ago to stabilize the bank; not the smaller, also notorious Japanese knotweed (Fallopia japonica). But you don't care about botany, do you? No, you and your whiney weed-infested fellow travelers only care about getting rid of the stuff, right? Buncha weasels. You know how long it took me to look those names up???!!!

Alright, alright. There are essentially two ways to get rid of overgrown, tenacious, deep-rooted weeds that can regenerate from the tiniest bit of root left in the soil.

#1: Chop and Smother. Cut the plant off at ground level, drive a stake through its heart and trash it. (Obviously, be careful with poison ivy--and bamboo, which can be VERY sharp-edged.) Then immediately cover the entire area with something REALLY thick and heavy, like me or some old carpeting or sheet metal. Then cover THAT with lots of wood chips or soil. Watch the edges for sprouts; pull (and taunt) any you see, or spray them with vinegar or herbicidal soap.

#2: Chop and Nuke. Cut as above and then treat the soil with one of these:

"Greensense 20% acidity vinegar". White vinegar that's four times more potent than the household variety. Drench the soil with it, preferably in the middle of a dry spell. You'll lower the pH down to around 3--too acid for anything to survive. Fertility and soil life will eventually return naturally, or you can raise the pH back up after a few months with wood ashes or lime. Available in stores in the Southeast, Rohde's in Garland, Texas (near Dallas) will sell you a gallon for $10.95 plus $8.50 shipping; call 972-864-1934, or visit www.beorganic.com or www.greensense.net. SAFETY NOTE: Vinegar with such enormous acidity is really caustic! You have to be careful not to get any on your skin or eyes--gloves and goggles are a must!!!!

"Greenergy Blackberry & Brush Block". A somewhat similar West Coast product (apparently, wild blackberry vines attack people's cars and children out there), containing 8% vinegar and 5% citric acid. You can get a gallon from Professional Turf Center in Portland for $36 (includes shipping); call 1-800-894-7333 or go to www.foodwebonline.com and click on "store".

Or try using a LOT of regular household 5% white vinegar, which goes for about two bucks a gallon. Empty a gallon a day on top of the infested area for a week or so in the middle of a real dry spell. Then test the pH; if you got it down to 4 or below, they're dead, Jim!

And if you're REALLY REALLY serious, Nuke AND Smother.

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