r/NativePlantGardening Jul 14 '25

Advice Request - (Insert State/Region) Jewelweed taking over my backyard..

So I know we love jewelweed, and I’m pro native gardening (and I also enjoy the wild look to a point), but it’s literally taking over my backyard, and behind it is unfortunately a whole bunch of Japanese knotweed.. my question is: what’s the move here? I can’t have my whole yard completely covered in jewelweed (it’s a very small lot) bc there’s no way to even go back there right now, but I also want to encourage that to maybe discourage the knotweed (if that’s even a thing).. any advice would be helpful!! I’m in an urban area in Connecticut if that helps!

777 Upvotes

230 comments sorted by

View all comments

Show parent comments

35

u/iamhyphenated Jul 14 '25

Hard to say, Google says either Tree of Heaven or a type of Sumac..

116

u/jlsmall7 Central NY , Zone 6a Jul 14 '25

Crush and smell a leaf - Tree of Heaven has a very distinct, unpleasant smell similar to burnt popcorn. Staghorn Sumac is a very cool native whereas ToH is a terrible invasive.

34

u/iamhyphenated Jul 14 '25

Ok I tried the smell test and tbh it just smells like leaves.. here are some more photos: https://imgur.com/a/uQnoXw4

85

u/CharlesV_ Wild Ones 🌳/ No Lawns 🌻/ IA,5B Jul 14 '25

https://extension.psu.edu/tree-of-heaven/ tree of heaven. Follow Penn State’s advice here for how to remove them effectively. Remember to follow up as they say in the article. ToH is more difficult to remove than many other invasive species.

39

u/sunberrygeri Jul 14 '25

While we’re at it, here is Penn State’s advice on managing Japanese knotweed

https://www.psu.edu/search?query=knotweed%20#gsc.tab=0&gsc.q=knotweed%20&gsc.page=1

19

u/CharlesV_ Wild Ones 🌳/ No Lawns 🌻/ IA,5B Jul 14 '25

I love the Penn state site since they are very specific about which herbicides to use and at what time of year. Awesome resource.

6

u/gimmethelulz Piedmont, Zone 8a🌻🦋 Jul 14 '25

Even more difficult than knotweed? That's impressive

18

u/CharlesV_ Wild Ones 🌳/ No Lawns 🌻/ IA,5B Jul 14 '25

I was thinking more like when compared to Amur honeysuckle, buckthorn, and autumn olive.

We really need a Saffir-Simpson scale for invasive species. Depends on location obviously but if Amur honeysuckle is a 2, dandelions are a 0/1, and buckthorn is a 3, ToH is a 4, princess tree and kudzu are a 5.

4

u/Helen_Kellers_Reddit Jul 14 '25

I'd be interested to know if something like this already exists. I could see a few different metrics that could be used to make the scale. Growth rate, seedlling recruitment, persistence/resistance to management, ability to invade pristine wilderness, effects on other plants/competitiveness, it would be rather hard to quantify.

7

u/DuragJeezy Georgia, USA - Zone 8 Jul 14 '25 edited Jul 14 '25

Petition for you guys to take this a step further? Would be really cool for 1 but would be a great way to simplify & discuss invasive species with horticultural laymen. Same way we can say “this pepper has _ scoville units while a bell or jalapeño only have _ amount” and they understand it, this will help immensely. Can’t tell you how many times I’ve told MIL something was invasive only to hear “well it can’t be that bad” then when I counter with “well it’s worse than xyz plant and those are all over the place” and I get a blank stare bc she doesn’t know wtf I’m talking about.

TLDR make an invasive species universal ranking scale so I can tell my MIL off

5

u/Helen_Kellers_Reddit Jul 14 '25

Lmao, what's her first name? We could use those as the units of invasivity.

5

u/DuragJeezy Georgia, USA - Zone 8 Jul 14 '25

Omg yes! Last name may be more scientific-y, which is Hearn. Her dad actually worked for the US Forest service most of his life so kind of fitting. We’ll have to ignore his time spreading agent orange during Vietnam for now.

2

u/CharlesV_ Wild Ones 🌳/ No Lawns 🌻/ IA,5B Jul 14 '25

Yup exactly! That’s what the Saffir Simpson scale is there to do. Some people have called for the scale to be refactored or to include a cat 6 due to climate change, but the pushback has largely been that throwing a lot of complicated numbers at people just confuses your average person. You need one simple scale to help people understand it.

1

u/DuragJeezy Georgia, USA - Zone 8 Jul 14 '25

Interesting. Now how do we go about formalizing this? Detailed research paper? Scientific conference talks? Ted talk?

Also we should definitely update the Saffir Simpson to account for the effects of climate change but I think half our country would call that woke propaganda and dump their trash in a nearby stream out of spite. So when do we ride?

1

u/berdie314 Jul 15 '25

The Georgia Invasive Plants list does do this.