The concept of “native” is a human construct. There’s no such thing in biology. There is only current occupancy, with the species occupying any landscape changing over time. Sometimes turnover is very slow, and at other times very rapid. We are in a period of rapid change right now, driven largely by human activity. Species are having to move, if they can, in response to human-induced environmental changes. And we are physically moving plants and other organisms around the globe. Animal transport of other biota is nothing new, but human technology and ingenuity have certainly brought animal-assisted migration to new heights and weirdness.
Animal-assisted plant migration takes two forms – active and passive. Jays transporting acorns and planting them on a hill a mile away is active. Ducks eating Alisma seed and defecating them in a marsh 500 miles away is passive. Humans engage in both active and passive assisted migration, and have done so since our emergence as a species. Our innovations in this process are the scale, intention and selectivity of it, which reaches far beyond the selection and movement of acorns by jays. We have opted to actively move all kinds of plants – not just food plants, but also fiber plants and ornamental plants, at an immense scale.
Modern humans are also driving global, passive transport of plants to a level unrivalled by any past circumstance with the possible exception of continental collisions. But continental collisions brought two continental floras and their associated faunas together en masse. We, on the other hand, are, either intentionally or not, plucking individual species of plants and critters by the tens or hundreds of thousands from one land mass and dropping them in another, and in the process dissociating them from their natural systems and associated biota. Released from predation and disease, these unwilling migrants sometimes explode in their new locations, creating biological shock waves that spread out and disrupt whatever they encounter, and in the modern era it is impossible to overstate the ecological impacts of this phenomenon. In the words of Mike Newton, one of the most accomplished silviculturists in the history of the field, the implications of our wanton introductions of plants, animals, fungi, bacteria and viruses simply “boggle the mind.”
Whether you have considered this situation or not, and are therefore suitably boggled or not, this is where we are at. The process is so far down the road that every natural ecosystem on the planet, so far as we know, has been irrevocably affected or in some cases, so completely altered as to no longer functionally exist. Ecosystems of the Northwest are no exception.
So this brings us to the question: what is native? As plants themselves migrate, and in some cases migrate great distances very quickly, are the pioneer plants native beyond their historic ranges? The tribes moved plants all around North and South America, and even between the two continents. Are these plants native? How is the Tribes’ assisted migration of plants qualitatively different from what European have done? Are the tribes themselves native? What about white people born in the Northwest? Are they native? The bumper stickers say so..
The truth is there are no natives. We found a 5000-year-old point at a Tualatin site in 2010 apparently unrelated to the Kalapuya, who are relatively recent arrivals here in the Willamette Valley in the context of 20,000+ years of humanity on this continent. The pre-Clovis tribes that preceded all of the modern tribes were migrants, and they were pushed aside by the modern tribes, all of which moved and expanded, or withered and were overwhelmed by nearby competing tribes in the millennia since their migration from Asia. Territories were lost and gained. Tribes came and went.
Humans and all of the other biota on Earth are migrants, and the history of life on Earth proves this beyond a doubt. As the Earth beneath us is constantly changing, it’s either migrate or die. So this is where we are, and this is what we have to work with. Our ancestry is of historical interest, maybe, but it has no bearing whatsoever on our trajectory from here on. The only things that matter to what happens next are the land itself and the living beings that are here now, no matter how or when they got here.
So these plants..these poor, maligned invasive plants. What are we going to do with them? We can’t possibly kill them all. I find it absolutely hilarious that we are still spending good money spot-spraying garlic mustard in the Tualatin Valley. Meanwhile, there are dozens of equally “invasive” plants growing shoulder-to shoulder with garlic mustard that we have chosen to ignore. Melissa, Geranium lucidum, Hesperis – the list goes on. I would argue, on the evidence, that Geranium lucidum is a more impactful weed locally than Alliaria. Why are we picking on Alliaria? At least we can eat it in a pinch (not my favorite wild green, though. Help yourself!)
It is time to take a future view. A thousand years from now, if we are fortunate enough to be here, humans are NOT going to waste time and resources killing garlic mustard, or much of any weed we are wringing hands about now. Can you imagine it? At some point, we are going to look around, and it’s all going to be just as native as we are. This is already happening, of course. Ask the average Northwesterner if their neighborhood blackberry patch is native and they’ll be thinking to themselves “who is this fool?”
We have opted, as I have said many times now, to live and let live here at Scholls Valley. This means that my back yard is as much weeds as grass. And guess what? The birds prefer the weeds! Check out these lovely lesser goldfinch feasting on Hypochaeris seeds this past August:
Obviously, I am not a wildlife photographer. Still, it is clear this native bird couldn’t be less concerned about the non-native ancestry of such a lowly weed, despised as it is by Chem-Lawn types and golf course managers. The goldfinch are getting what they need, making the most of what is available to them in their territory now, today. We need to take note. This is a strategy for success. The nativist phony-baloney is not.
Don’t get me wrong, I love our “native’ flora, and I have spent my entire career working in it and learning from it. And I hope there will be space in the future for as many Northwest plants as possible. We (and you, the buyers) may play a role in giving them a better shot at that. I hope so. We still have hundreds of thousands of native plants looking for good homes right now, so please do take a look at our availability and buy some. But you will note that there are a small number of adventives in the mix – two to be exact. We have begun growing these plants for good reasons. They already are present here in our flora, and they both serve important functions for wildlife and humans. Whether you like it or not, they are going to be part of our ecosystems for the foreseeable future. So there are good reasons to go ahead and include them in you plans. These are Prunus avium (bird cherry) and Juglans hindsii X nigra (the so-called “Oregon walnut”), the latter pictured below in a woodland along the Tualatin River.
These trees have fantastic form and superior wood characteristics. They are good additions to the arborescent flora, especially given the expected demise of ash. They are also both food plants. Our descendants will almost certainly thank us for provisioning their landscapes with these excellent trees. The seedlings we have produced are stunning, robust plants. So please buy some and plant them for the people of tomorrow.
Ciao,
-George