3 Reasons Invasive Species Aren't a Big Deal

Hey Amanda,

Life couldn't be better. Dogwoods and azaleas are blooming everywhere. Yesterday, I saw a blue heron catch a fish in the creek. Wisteria is forming little bundles of smokey purple in the pine trees all over the place, and the smell is fantastic.

via Virginia Sanderson

They tell people around here that wisteria is a super destructive invasive. In my mind I'm thinking, "a  weed that is fragrant, beautiful, and attractive to bees...where's the negative here?" Seriously though, dividing vegetation into two categories-- native and non-native-- is a stagnant way of looking at nature. Nature has been introducing and exterminating "invasive plants" since the Devonian era. Here's three reasons why invasive species are a non-issue in the gamut of things affecting native ecosystems.

1) Self-contained  ecosystems are a fiction.
There are no hermetically sealed acres anywhere on the planet. Globalization does not just apply to Coke, but to parasites, fungi, and viral infections. Case in point,  the entire East coast of the US used to have its own version of the redwood. It was 50 feet tall and 5 feet in diameter--the American Chestnut tree.

Family standing in front of American Chestnut, circa 1901
viaThe Roanoke Star

By the first decades of 1900's, global trade introduced Asia-endemic Chestnut Blight to the Eastern seaboard, killing every American Chestnut in it's native range with so few exceptions that they're listed on the bottom of the wikipedia page. Efforts to save the American Chestnut from extinction all revolve around out-crossings with Asian chestnut species, because the American Chestnut does not have the genetic material to survive the modern world. To argue that we can import goods without importing unintentional consequences is silly. And it's ridiculous to suggest that we're going to return to continental isolation of our own volition.


2) Native Ecosystems Include Animals

Yeah, I heard the smell of human hair really scares the deer away....
via Alex Berger

Native species thrive in a specific circumstance where predation and regeneration are in balance. Plants evolved with particular predators and pollinators in mind. The fact is the landscape acts nothing like it did in 1700 so why insist that the same plants thrive in it.  Deer populations are three times as dense as they were in the 1700's. We have an out-of-hand deer population that eats a lot of seedlings, because we don't have many wolves.

We spay and release stray cats because it seems inhumane to kill them, ignoring the fact that we're  artificially inflating the number of small-game predators in our area. And that's how we end up 3 billion birds poorer. Birds are one of the main, and in some instances the only way seeds are spread.

Humans irrevocably change the fauna that lives around them, and that means changes in the flora.

3)Maybe Invasive Species are One Way Nature Adapts to Change

"Invasive" is just the another way to say well-adapted. Much more has changed since 1700 than the animal populace. Hardiness zones have changed. Rainfall patterns are different. Streams and rivers no longer follow their natural course. Nature does just fine with adapting to all of this. But adapting, by definition means change. A lot of plants do better in milder winters; some do worse. Some need wet springs. Some need hot, dry summers. Some need snowfall. Some need humidity. The thing is that most plants are persnickety about how they germinate. It's not just competition from foreign species that makes things difficult for some species to grow where they use to thrive.

The destructive and beautiful Kudzu.
via Kitten Wants

"But, kudzu."

Let's be clear, I wouldn't wish kudzu on my worst enemy. But...it's drought tolerant and nitrogen-fixing. It's edible. Livestock love it. Ecologically, there are much worse things than kudzu. I'd rather have acres of kudzu than asphalt. Both inhibit the germination of hardwoods, but one of them also increases soil erosion in surrounding areas, provides no oxygen, and releases toxins in the air. Just sayin'

tl;dr Frankly, I don't care if a species is invasive.We should be preserving native species from extinction because biodiversity is important, not because they were here first.

If we're playing the "I was here first" game, the Dinosaur snack Ginkgo biloba wins by a landslide.
Too bad the female trees literally smell like vomit.
via University of Wisconsin-La Crosse ...via Berkley

Your Irresponsible Plant Lover,
Stephanie