Knotweed

[JohnPowers]

The Adirondack Almanac had a piece on NY introducing a bug that kills knotweed. I know the law of unintended consequences but if you knew the upper D prior to knotweed you have to wonder if the gamble isnt worth it.

 

[Nymph-wristed]

And places like the Lack would have no cover w/o it... Interesting, though!

 

[bearfisherman]

Would love to see it gone with introduction of natives afterwards. Knotweed is one of the worst invasives.

 

[Sruflytyer]

Knotweed sucks and bugs are safer and cheaper than herbicide. Hope it proves to be effective

 

[redietz]

Sruflytyer wrote:
Knotweed sucks and bugs are safer and cheaper than herbicide. Hope it proves to be effective

Me too. Several studies out west have shown that stream side knotweed adversely affects insect populations in the stream, especially of caddis flies. (Apparently, the larva can't eat the leaves and it crowds out plants whose leaves they can eat.)

Knotweed has become completely out of hand along the Gunpowder in Maryland in the last couple of years. It's everywhere.

 

[Mike]

In coal country knotweed grows where nearly nothing else will. In fact, that’s how some of it, if not all of it got here in the beginning. It was a promising plant for strip mine reclamation because it took hold when planted on mines where the acid overburden had been left on top when the mines were back filled. Each year it collapsed and broke down into humus and eventually soil. There was no other soil on the mine surfaces. Experimentation with the plant for that purpose was taking place in 1976 in Clarion Co. It was the first time that I had heard of or seen the plant, which was being called Japanese Fleece Flower.

It does well along mine acid and iron affected streams in Schuylkill Co. Substantial terrestrial insect forage falls from the plants and keeps the wild brook trout well fed (often quite plump) all summer and early fall. These streams support very little aquatic insect forage, at least when they first start making their comebacks.

 

[krayfish2]

Anyone ever walk a half mile through knotweed? I did once and never will again. While the insect sounds promising, I'm very skeptical about introducing any non native species. After all, it's never backfired, has it?

 

[Lou]

Where I fished the path got so choked that I brought the good old fashion hand sickle with me to clear the way!

 

[salvelinus]

North central PA has a lot of this in places. And wild parsnip too. Nasty stuff.

 

[dryflyguy]

When I was kid, I thought it was some kind of bamboo.
I remember chopping my way through it on many hikes in the woods.

During my hunting days, I would always try to give it a wide berth.
It's very noisy to trample through.
And even though it can get very thick, it never seemed to harbor any wildlife anyway.

And, as already mentioned, it can certainly make getting to fishing spots hard too.

So, I've always had a disdain for it .

However, I've come to find out recently that it can be eaten.
Supposed to be best in the spring when the new sprouts are small and tender.
But have never tried it. Maybe someone out there has?

Have also read that it has some medicinal properties. Kind of a natural antibiotic.
It's extract is sold as a remedy for lyme disease.

So, maybe it's not such a nasty weed after all?

 

[troutbert]

Invasives are very common along our streams.

Multi-flora rose is nearly everywhere.

Shrub honeysuckles are very common along limestone streams and some of the fertile freestone streams.

Autumn olive is very common.

Norway maples are common along Spring Creek.

European (black) alder is increasing rapidly along Spring Creek. There is a huge amount of it just upstream of the hatchery, and on the same side, at Fishermans Paradise. And I've seen quite a bit of it from the lower end near Milesburg the whole way up through Spring Creek canyon.

 

[HopBack]

In coal country knotweed grows where nearly nothing else will. In fact, that’s how some of it, if not all of it got here in the beginning. It was a promising plant for strip mine reclamation because it took hold when planted on mines where the acid overburden had been left on top when the mines were back filled. Each year it collapsed and broke down into humus and eventually soil. There was no other soil on the mine surfaces. Experimentation with the plant for that purpose was taking place in 1976 in Clarion Co. It was the first time that I had heard of or seen the plant, which was being called Japanese Fleece Flower.

It does well along mine acid and iron affected streams in Schuylkill Co. Substantial terrestrial insect forage falls from the plants and keeps the wild brook trout well fed (often quite plump) all summer and early fall. These streams support very little aquatic insect forage, at least when they first start making their comebacks.

Well at least you have tempered my disdain for the stuff!

 

[salvelinusfontinalis]

Nymph-wristed,

On the Lack i totally agree. I think it is fair to say it certainly does not hurt the fish.
Still not good, but it grows up between tires like no other.:lol:

 

[Classicriver]

I have been fighting that weed in the Catskills seemingly forever, and it gains every year. I have never seen any wildlife or insects in the stuff. I read someone's account recently of fish eating terrestrials along knotweeded banks of the river. I have never seen the stuff attract bugs or trout.

A new magic bullet bug will probably bite us in the rear at some point though!

 

[salvelinusfontinalis]

I was reading somewhere ages ago about knottweed in Schuylkill as Mike describes.
His assessment about the brook trout is spot on for not just there but in the general region.
Plump healthy fish and the knottweed is particularly responsible for comebacks.
I should know if fish it a bunch.

Its not all doom and gloom.
Still dont like invasive plants.

Shame it wasnt done another way.

 

[larkmark]

Probably holds banks together. Guys have a hard time casting under it which protects the fish and since lots of fly fishermen don't care about fishing in higher temps I am all for anything that helps fish not get caught

 

[Canoetripper]

This seems to be similar to Kudzu in that it is an invasive plant native to Japan. I have seen Kudzu overtake trees and buildings in all the years I lived in the south.

 

[redietz]

larkmark wrote:
Probably holds banks together. t

No. It's shallow rooted, and crowds out plants that do hold the bank together. It's a major contributor to bank erosion.

 

[cajungly]

The common name “Knotweed” is often used for the Genus “Persicaria”. This Genus includes many native species but there are several invasives. One of the worst among these is “Mile a Minute” or “Persicaria perfoliata“. This plant often grows in wetland/riparian areas not far from Japanese Knotweed( Reynoutria japonica). Both Japanese knotweed and Mile a minute are in the family Polygonaceae.

Mile a minute is sometimes referred to as “Knotweed” and this does have an associated weevil called the Mile a Minute Weevil. This has been introduced in areas with high invasions of MAM and has been quite successful. This weevil was tested quite extensively for potential ecological harm but it proved to be exclusive to Persicaria perfoliata.

I have not heard of anything specifically targeting Japanese Knotweed but I do hope that day comes. Many invasives can be seen as positives when looking at their function within a space, i.e erosion control. This will never measure up to having fully functioning native plant communities though. The more invasive species we have here the harder it will become to restore these plant communities.

 

[JohnPowers]

https://www.adirondackalmanack.com/2020/08/biological-control-for-japanese-knotweed-tested-in-new-york.html

Info on knotweed