Invasive Plants of the Southeast-- Specific Issues?

I’m currently working on a zine about non-native and/or invasive plants that will -hopefully- have a nice balance of humor and well-researched actual facts. Unfortunately this is one of the fact-heavy party and I need as much information as possible!

People often don’t understand the gravity of invasive species encroachment, or fail to understand the “why” behind the multitude of problems they create. Just saying they displace native species and create monocultures of mostly/entirely ecologically useless species isn’t enough for most people to be convinced, so I’m looking for specifics.

Off the top of my head, I’ve come up with:

  • spread of tick-borne illness (seen in Japanese Barberry, a new invasive here)
  • hitchhikers (spread of fungi such as the Chesnut Blight from introduce Asiatic Chestnut species spreading and killing off our culturally/ecologically significant Ozark Chinquapins, external-to-us insect examples such as Chinese Lanternflies… hoping to find a local example though)
  • fire hazard (eastern red cedar, which will probably get its own page for nuance since it’s technically native)
  • Allelopathy (Ailanthus)
  • degredation of water quality (Amur Honeysuckle)
  • barriers to migration of aquatic and terrestrial organisms
  • toxicity to native species (Nandina berries vs. Cedar Waxwings)
  • water usage impacts (cedars, again)
  • negative impacts on sensitive specialist bees
  • differing morphology of similar plants (Johnson Grass vs clump-forming Bluestems, both “grasses” broadly, their impact on Bob White Quail)
  • displacement of native species reducing population size and thus genetic diversity, lowering ability of native species to adapt to climate change

It’s targeted towards invasives in NW Arkansas, but it might be helpful even if you can think of something from somewhere else since we may have a different species creating the same concern. The project Invasive Plants of The Natural State has a pretty good list of the ones we do have, if you want to check for relevancy though.

Anyway, any additions would be appreciated!

I would especially love things with a citable study, but I think observation-based anecdotes can also be okay in many cases.

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The scholarly lit has a ton of examples and citations here. Some other potentials are:
Reduced/altered ecosystem services and human welfare:
https://www.researchgate.net/profile/Liba-Pejchar/publication/287527611_The_Impact_of_Invasive_Alien_Species_on_Ecosystem_Services_and_Human_Well-being/links/59d79cb80f7e9bc89ccd5a05/The-Impact-of-Invasive-Alien-Species-on-Ecosystem-Services-and-Human-Well-being.pdf
Hybridization with native species that can swamp native genetics
Disruption of food webs

And really just the fact that we don’t know what any given invasive species will do until after it has become invasive. It’s best to just use the precautionary principle.

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Might be difficult to find photos, but “before and after” really does a good job illustrating the difference between an invasive monoculture vs. natives. A good source is restoration projects, which show the “before” monoculture and “after” typically with more wildlife/plants.

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You already have a very wide range of topics. Look forward to seeing what comes of this. Here are a few additional suggestions:

Pollen allelopathy in plants such as dandelions (hasn’t been observed in the southeast)-- (https://www.pollinationecology.org/index.php/jpe/article/view/286)

The crazy history of “sterile” cultivars, especially of Callery Pear and Miscanthus, e.g. M. giganteus. I don’t have any recommended sources on hand.

The history of Kudzu. Here’s a fun article from 1973 where John Winterberry argues that Kudzu failed because it failed to live up to expectations and touted new, better plants such as Lespedezas (which now have invaded around 3 times as much land area as kudzu according to some estimates). Rise and Decline of the “Miracle Vine”: Kudzu in the Southern Landscape (jhu.edu). If you really want a trip, here’s an article that uses the Winterberry paper to argue that Kudzu has become native. EBSCOhost | 103353459 | When an Exotic Becomes Native.

If you want to expand the topic to insects, Apis mellifera reduces fruit set by decreasing native bee populations–(https://www.nature.com/articles/s41598-021-81967-1)

As a note, the Nandina domestica/cedar waxwing issue is less of an issue than people make it out. It has been documented, once, and it likely has happened since, but… cedar waxwings are known to kill themselves by eating too many native hollies, too. Cyanide levels in Nandina fruit is variable and it is usually at or below the level of comparable native fruits, though it can get much higher in some conditions. The green fruits have much more cyanide and the ripe fruits have much less. (https://digitalcommons.usu.edu/poisonousplantresearch/vol5/iss1/1/) Yes, we should not plant Nandinas, but we also should not overstate the evidence.

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Since zines tend to be rather short, I wouldn’t expect you to be able to cover all of these issues. Your initial list has 11; how many pages will the zine be? And how much of it will be graphics vs. text?

The zine piece won’t have an in-depth look on them, just kind of a cursory view. I do need to do a separate text-based research thing for it to prep though, and I’m actually being asked to consider doing a real write-up for our extension office that would be in-detail :) so I definitely would need both the full lay-out of things plus the ability to summarize!

Part of the benefits of a zine format is flexibility though; there’s definitely room to go in-depth on at least a few things.

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Japanese climbing fern - smothers trees/bushes and fire hazard in east Texas forests
https://www.texasinvasives.org/action/report_detail.php?alert_id=13
https://www.texasinvasives.org › resources › publications › 05_JCFern_TFA.pdf

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Thanks for doing such great work.

Somehow the same happens here. Kudzu is a policy species and addressed as one of the most frightening, terrible, concerning, ond so on invasive species. Of course, I do not want to mean that it is not so but other alien species sharing with kudzu many characters (in few words, they are all fast growing lianas) in some areas are far more common and show an extremely aggressive behaviour (one among all, Vitis…). I have tried a couple of times to raise this issue. No answers… Wouldn’t it be because Vitis is an economically important species? I do not know if this is a funny fact.

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Feeling really uneasy about the potential for blaming foreign sources for invasives here. Hoping you will explore what role our consumer culture plays. Hope you will consider pointing out how N. American species invade overseas, too, so that readers don’t feel like they are under attack.

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I don’t know about plants, but I know my local red swamp crawfish and red-eared slider turtle are very problematic outside their home range.

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Not significant in your state yet (see here), but after reviewing this observation or the the photo on wiki, invasives like Tribulus terrestris can physically injure people or pets.

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You listed Eastern Red Cedar as “technically native”. That is a native species, so it really should not be included. Otherwise you’re confusing the issue - so it’s not exotic species you’re talking about, it’s any mis-behaving or problematic species?

Eastern Redcedar is native to Eastern North America, but it isn’t native to prairies, per se–when it moves in and becomes a monoculture, it really is changing the native ecosystem into an unnatural one (I’m not claiming there were never cedar monocultures pre-Colonial times). You are correct though that these issues are nuanced and people have divergent intuitions and conclusions based on the data, so the topic should be handled with care.

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