Welcome back to Climatific, a free, weekly read that breaks down climate science so it makes sense — not for scientists or researchers, but for everyday people trying to understand the planet we live on, what’s happening to it, and why it matters.
As an aspiring plant dad and identifier, I’ve never met a plant that chose where it was born. I have, however, come across plenty that have chosen where to thrive, oftentimes at the detriment of everything around them. For millions of years, plant species worldwide have evolved in lockstep with their local climate, soil, hydrology, and neighbors, building finely tuned relationships with the ecosystems they call home. Once those relationships are disturbed, however, some plants — and, yeah, I am looking at you Tree of Heaven (some angel you are 😠) — go from garden guardians to full-blown herbaceous invaders faster than you can say “invasive.”
Why?
Well, buckle up, plant nerds. In this issue, we’re going to stop beating around the burning bush and get right to the root of it!
If you’re a new subscriber, catch up on past issues of Climatific and learn more about who we are here:
🌎 First, Let’s Get Our Terms Straight (Because Scientists Sure Can’t)
Here’s a fun fact: scientific literature currently uses no fewer than 20 different words to describe species that live somewhere other than their biological birthplace. “Aliens.” “Foreigners.” “Invaders.” “Exotic.” You’d think they were writing a reality TV casting call, not a peer-reviewed research paper.
Despite their best efforts, all of that creative vocabulary has created one giant headache that no amount of butterbur can fix. The frequent interchangeable use of these terms has muddied important concepts and overall levels of understanding in the field of invasive species management. So, in the spirit of getting out of the weeds and doing what scientists struggle to do, lettuce define our terms.
Native species: An organism that exists in a region without any direct or indirect human help. In North America, we generally recognize native species as those present on the continent before European settlement and colonization.
Nonnative species: An organism that has been accidentally or deliberately introduced to an area outside of its normal range, often with little (or a lot of) human help. While only a fraction of established nonnative species are considered ecologically harmful, the second they start causing damage, we are allowed to label them as an…
Invasive species: An organism that is nonnative to its ecosystem and whose introduction does or is likely to cause harm to the economy, environment, or human health.
So, nonnative ≠ invasive. But, invasive is always nonnative. Got it? Great. Moving on.
🌎 So, What Makes a Plant “Invasive” Anyway?
While not every nonnative plant earns the invasive label, the ones that do tend to share a very specific and frankly impressive (if not, diabolical) skill set:
🌱 They grow and mature rapidly
🌱 They produce an almost offensive number of seeds
🌱 They have high germination rates
🌱 They spread in multiple ways
🌱 They have longer growing seasons than native plants
🌱 They are wildly adaptable to different environmental conditions
🌱 They outcompete native species for resources
🌱 They are super selfish and alter soil habitat conditions to better suit themselves
🌱 They lack native predators and easily shrug off pests, pathogens, and predation
🌱 They are expensive to remove, control, and manage
The more of these traits a plant species checks off, the easier it becomes to establish, spread, and resist eradication. Unbe-leaf-able, right? Think of it like a video game boss fight (Plants vs. Zombies, I guess) — the more power ups they’ve collected, the worse your odds become.
The final boss from Plants vs. Zombies, Dr. Zomboss | Credit: Insert Name Here
🌎But Where The Heck Did They Come From? I Didn’t Invite Them!
Great question! And no, you probably didn’t — at least not intentionally.
Invasive plants arrive in new areas through a variety of pathways of which there are two distinct types: natural and human-caused. Natural pathways like wind, water, and animal digestion exist, sure, but they pale in comparison to the ones humans have built. The biggest culprits, you ask?
Shipping: Global shipping containers have been one of the largest facilitators of invasive species introductions. Plants hitch rides in wooden pallets, nursery products, agricultural goods, and even ship ballast water. Once unloaded at port, they’re distributed even further by trucks and trains. It’s a five-star travel package for plants that your backyard may end up paying for.
Horticulture: The horticulture industry imports, propagates, sells, and plants a huge variety of flora, many of which are nonnative to their new homes. Most stay put or spread without major consequences. But some become the ecological equivalent of a houseguest who overstays their welcome and eats all of your food.
Travel, Tourism, and Recreation: Large groups of people, vehicles, and vessels from geographically diverse areas create perfect pathways for invasive plant propagules — that’s a fancy word for any vegetative structure capable of growing a new plant — to spread. Even your favorite hiking trail or kayak route could be carrying stowaways. Check your boots. Check your boats. Seriously.
Construction and Industrial Operations: Invasive plants love disturbed soil, probably more than I love doing the lawnmower on the dance floor (hey, at least it’s a contraption that somewhat helps with weed control). Road-building, land clearing, mining, grading, mowing — all of these create ideal conditions for new infestations.
🌎 Is Climate Change Giving Invasives More Room to Grow?
The short answer is yes, and the facts might just knock your stalks off. Climate change and invasive plants aren't two separate problems running parallel to each other. Rather, they are two forces that compound on one another. As the climate warms, the number of invasive species on every continent is expected to increase by 36% by 2050.
Global terrestrial and marine invasive species distribution by continent. *Note that this includes both animal and plant species. Credit: The Carbon Brief
And those traits we covered earlier that already make invasive plants so hard to stop? Climate change rewards every single one of them.
Climate Change = Expanded Range
Cold winters have historically been one of nature's most effective pest control systems. Hard freezes kill off seeds, limit germination windows, and keep many invasive plants locked out of regions they'd otherwise colonize. But as average temperatures rise and winters grow shorter and milder, those natural barriers are quietly disappearing. Species that once couldn't survive north of a certain latitude are now establishing themselves in ecosystems that have never had to defend against them.
Droughts, Disasters, and Disturbances, Oh My!
Invasive plants are opportunists, and love to set up shop in disturbed soils. Climate change is dramatically increasing the frequency and intensity of exactly these kinds of disturbances through more severe droughts, floods, wildfires, and storm events. Each event clears established native vegetation, offering up open real estate that invasives are perfectly equipped to claim first.
Carbon Dioxide Is Like Miracle-Gro for Invasives
As atmospheric CO₂ levels rise, plants that can quickly capitalize on elevated carbon tend to grow faster, produce more biomass, and reproduce more aggressively. Research consistently shows that many invasive species respond to elevated CO₂ more strongly than native species, which hands invasives a biochemical advantage while native ecosystems struggle to keep up. Way to kick the underdog while they’re down, eh?
🌎 The Sunny Side
Scientists, land managers, and conservationists are developing increasingly sophisticated tools to get ahead of invasive spread, but the buck doesn’t stop with them! Community-driven early detection programs, like the Statewide Eyes Program in Maryland, are turning everyday hikers, gardeners, and yes, aspiring plant dads, into a frontline monitoring network.
Apps like Seek, PlantNet, and PictureThis also exist at our disposal to help identify and report invasive plants wherever they take root. I identified, tagged, and ripped out some Garlic Mustard the other day during a walk through my neighborhood and, man, did it feel good!
It's also worth remembering that not every nonnative plant is the enemy. In highly urbanized areas, invasive plants are sometimes the only vegetation willing to grow, removing CO₂ from the air, reducing stormwater runoff, and providing habitat where native plants simply won't take hold.
So, our relationship status with invasives is… complicated, as most things in ecology are. But that complexity is exactly why understanding the science matters, and why every set of eyes counts.
🌎 In the Forecast
Having reached the end of this week’s issue on invasive plants, I sincerely hope that you were able to weed through it and reap something useful.
The takeaway, if there is one, is this: invasive plants and climate change aren't a chicken-and-egg problem. Instead, they're a cycle, and that cycle is accelerating largely thanks to the conditions climate change creates. And as they spread, they degrade the very ecosystems that help buffer us against further climate impacts.
Thanks for reading plant nerds! Tune in next week for a very special issue of Climatific, where we shift away from the slow-burn ecological threats we covered today to something a little more…explosive 🎆
Giphy
Have a specific topic on climate science you want to learn about? Let us know. All responses are anonymous!
🌎 Hungry for More Science?
👋 About the Author 👋
Wylie Feaster is a Climate Change Training and Education Specialist for the State of Delaware. He has a B.A. in Environmental Studies from the University of Delaware. In his free time, you can find him reading on his roof, managing his music blog, and getting super lost in the woods.
Got feedback? We want to hear it.
Help us reach more people! Share Climatific with your family and friends here:
Thanks for tuning in. See you next Tuesday!
Stay curious,
Climatific
