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Japanese Knotweed

There are several patches of Japanese knotweed encroaching on the southern sidewalk on Butler St. between Suydam St. and the 62nd St. Bridge. What can I do so that I do not have to carry the cuttings home with me? Is it ok to take a paper or plastic garbage bag with the cuttings in it on a bus?
2019-10-02 16:59:20
I'm not sure what you are asking and I'm not sure bike pgh message board is the best place for this. Japanese knotweed has a large underground rhizome biomass so simply cutting the stalks won't get rid of it. The city will need to spray herbicide, unfortunately. It will probably need repeated sprays to get rid of it. I'm not sure why you'd take Japanese knotweed cuttings home.
2019-10-02 17:48:50
Just hack it down and leave the clippings where the plant was growing. It’ll disintegrate within a few weeks. Better than the full grown plant, consider having done everyone a favor by leaving a “mess” behind. It will keep returning, but I’ve noticed that with this dry spell we’ve had lately, the stuff that was cut over a month ago is still only a few inches tall. So best bet is to hack at it a few times a year if you use this route often, because like Eric said this stuff isn’t going anywhere anytime soon. This really isn’t the forum for this, but I often wonder if eventually nature will rebalance itself and native plants and animals will learn to eat and compete with invasive species like this. Also, do our native plants invade Asian countries? Or are their plants so badass that they just come here and outcompete everything? Much like their scholars and businessmen.
2019-10-02 18:26:52
Personally, I think Japanese knotweed is a pretty plant just like Japanese, Korean, and Chinese women are pretty. At least Asian women do not block pedestrians and cyclists from traversing steps and sidewalks like their plants do. Since I have an appointment tomorrow, I will take some clippers with me and cut it down so that people can get through. Check out this post on my Instragram to see where I am talking about.
2019-10-02 19:12:42
311 it. If you bring back clippings and try to plant it in Aspinwall your neighbors are going to be upset when it invades their property. And the species invasion isn't just one sided. Species from all over the world spread elsewhere with trade.
2019-10-02 20:06:50
I'm knot planning on planting it in Aspinwall. Pun intended.
2019-10-02 20:53:00
I've had years of experience trying to eliminate or reduce japanese knotweed along the trail near Kennywood. I'm not a botanist but ... cutting the plant back every month or two during the growing season (April to October) helps stunt its growth. If you keep that up for 3 years or so, you could kill an isolated clump of it. But where the plants are well established, the rhizomes (roots) underground are tens of feet long and help the plant to regrow fast and strong. Some people talk about a need for extreme care with cuttings (bagging & removal, throw into a nearby volcano, ...) but I suspect that's only true for roots, not above-ground cuttings.
2019-10-03 10:23:31
My method was effective, when I kept at it. I pulled up the whole plant, as much of the rhizome as I could get, and just piled it all in one spot. I eventually pulled up a 40-foot square, and the pile was five feet high, six feet across, and ten feet long. The 2016 growing season was the last I worked at this, so I should go back and see how far down the pile rotted to in that time. My limiting factor was deer ticks. They’d get all over me, such that I had to strip naked prior to entering my house, for the 15 minutes it took to perform a proper inspection of both the outside and inside of all (and I mean all) clothing. Because I sure as hell wasn't going to bring any in the house if I could help it.
2019-10-03 12:39:57
Shop’n Save sells japanese knotweed honey. It’s actually fairly pleasant. Comes from Hickory PA, not far from here.
2020-01-05 13:56:08
Is that Shop'n Save in Lawrenceville which is the only one I can get to?
2020-01-06 19:41:38
My store is Pines Plaza in Ross. I haven’t looked elsewhere. It does tend to crystallize quickly, but put it in a small pot in an inch of water, over very low heat for a half hour, it remelts. Being warm at serving time also enhances the flavor.
2020-01-08 08:04:59
I prefer my honey crystallized- less drippy, does not run off toast as quickly, yet blends into tea easily.
2020-01-08 21:12:01
@Stu, Recently, I've been climbing East St. from the Gerst Way bridge to Perrysville Ave. It's a nice, gradual climb with a short, steep section at the approach to Perrysville. Ave. After that climb, I can easily reach Pines Plaza by doing      the following.
  • R. Perrysville Ave.
  • R. Center Ave.
  • R. Belleview Ave.
  • L. Rochester Rd.
  • R. Perry Hwy.
  • R. Harden Dr.
  • L. Schars Ln.
  • R. Perry Hwy.
I've been on Perry Hwy. between Westview and Sandle Ave. in the past. I believe the really dicey part is the climb north of the Westview Park shopping center. Babcock Blvd. and Rochester Rd. can be another option.
2020-01-14 20:04:31
You’re adding a lot of turns and distance with no discernible improvement. The journey on Center isn’t too bad. I don’t use Bellevue St because of the unnecessary hill. I do use the little alley across from Scholl’s Bike Shop, then go straight up Perry. I agree about the bit beyond Pines, but not for the reason you stated. The farther out you go, the less that bikes are tolerated. Sandle is immediately north of me but I never bike north, only south. As to knotweed, it’s not too big a problem on Perry. There are a couple outcroppings on Babcock that poke out into the road, forcing you into the lane. I’m never on Rochester on a bike.
2020-01-15 13:24:09
To me, the most dicey part is going through the business district just north of the horseshoe bend in Perry Hwy. as there are parked cars on both sides as well as being uphill. Conditions get better befween Rochester Rd. and the Ross Township business district south of Three Degree Rd. The alley you are talking about, Phil St., only gets you about 1/2 of the way to Chalfonte Ave. and the is even more hill past Chalfonte Ave.
2020-01-15 19:59:55
The alley that gets you out by the playground bypasses most of the parked cars. Beyond that, it’s a very wide lane. Heading southward through West View via Center, there are unavoidable outcroppings of knotweed in that residential area, and no alternative to path of travel. Point being, sometimes you just have to be in front of cars, and tough noogies for them.
2020-01-16 06:15:40
Nobody asked, but I'm ok with the japanese knotweed being discussed here. Perhaps more discussion should be had about this and other plants that encroach on trails and shoulders. In the same way just one badly placed pothole can cause you to adjust your line out into traffic, encroaching plants can force you further out than you may otherwise want to be. I ride the Highland Park Bridge frequently, and fortunately PADOT has done a better job of trimming the plants back on the ramp outbound, otherwise, when it gets overgrown, it forces you out into what is already a narrow chute (and no, I don't need to hear "just take the lane" advice, ok?). So plant talk has a place here, as far as I'm concerned.
2020-01-22 09:33:47
This spot on Babcock Blvd near Hastings Hardware in Ross once had a badly overhanging knotweed stand, pushing cyclists out into traffic. It took hours of work and a pair of broken eyeglasses to whack it back. It’s still there, but I haven’t touched it since 2016.
2020-01-25 12:29:42
It's early Spring and the best time to forage (not much foraging, since it's so invasive) and harvest knotweed. It's edible (it's been compared to asparagus, but is more like rhubarb) and a very healthful food (e.g., it is a major source of commercial resveratol). I've been picking the young shoots for the last few weeks and enjoying its culinary and health benefits--throw in soups and salads; stir fry it; make pies, puddings, etc. It's edible raw as trail nibble. But unadulterated, it may be a bit sour plain for some. You can Google for more info, but here are some references:
2020-04-16 06:46:51
I’d love to forage the stuff, but my most bountiful supply is also annually doused with herbicide, so I don’t dare.
2020-04-16 15:35:16
It's probably also covered in coronavirus.
2020-04-17 16:09:06
@StuInMcCandless If you venture out of McCandless I'm sure you will find less adulterated knotweed. It abounds everywhere. Eliza Trail, Steel Valley Trail, Carnegie Science Center, You're Grandma's Backyard, .... (I'm not sure where Granny lives, but I've been eating Polygonum cuspidatum from the other locations with no ill effects and possible protection from COVID19.) And @zzwergel don't mock the power of botanicals... knotweed may save us yet:  
2020-04-18 04:51:48 was gifted this recently. Not really a use for Knotweed plants, but does indicate they are somewhat useful.
2021-12-25 09:21:48
I'm less concerned with plants grown in a particular spot for cultivation purposes, and more with plants that obstruct traffic and force cyclists and pedestrians into traffic unnecessarily.
2021-12-25 14:42:43
FYI, a solution to the Japanese knotweed problem (Aphadora itadori, a tiny parasitic wasp that feeds on it) has been extensively studied and approved for release by the USDA. It's currently being implemented at a number of sites. Perhaps we could advocate for it here.
2022-01-05 10:14:26
My own plan is to experiment with a couple of stands I've waged war on in past years, using a couple different approaches I've read about over the years. I haven't paid much attention to this since I haven't been commuting daily (2018), so those stands have mostly grown back.
2022-01-13 16:12:42