Permaculture is a design system which focuses on how people interact with the rest of the natural world. David Holmgren, the co-founder of permaculture, describes twelve principles, with the first being ‘observe and interact’.
|By taking the time to engage with nature we can design solutions that suit our particular situation. The icon for this design principle represents a person ‘becoming’ a tree. In observing nature it is important to take different perspectives to help understand what is going on with the various elements in the system. The proverb “Beauty is in the eye of the beholder” reminds us that we place our own values on what we observe, yet in nature, there is no right or wrong, only different. [i]|
There is an uncomfortable reality for us to consider: we judge plants and animals almost completely on their usefulness to humanity, with a tendency to try and control or eradicate that which we don’t think belongs. Hence the use of the term ‘invasive’ species. We use the word invasive to describe:
|a plant, fungus, or animal species that is not native to a specific location (an introduced species) and which has a tendency to spread to a degree believed to cause damage to the environment, human economy or human health. [i]|
Notice that two of the listed concerns are about impacts on humans. As for invasive species damaging the environment, the number one cause for environmental damage is humans (habitat loss is the #1 cause of native species declining). The number two is so-called invasive species, which are almost always introduced by humans. So I’d like to play devil’s advocate and suggest a different approach to thinking about the biodiversity that exists in our local ecosystems. This is not to say that there are not some real problems and impacts related to non-native plants and animals dominating an ecosystem, just that the solution – more human intervention – is not going to help.
The reality is that about 97% of species entering a new ecosystem either do not survive, or else only in small numbers. For those that are more successful, the cause is usually human related; disturbed or contaminated soils, cleared areas, steep slopes.
Non-native species rarely displace a native species completely, meaning that new species increase biodiversity and enrich ecosystems in the majority of cases. Likewise, the cultural diversity in Canada is created by immigrants arriving here from many different countries.
Right now we seem particularly proud of Canadian immigration practices: there was an article this week in The Guardian’s international edition about the planned protest [Tuesday February 28, 2017] in Vancouver over the newest Trump building:
|…the addition of the Trump name to the skyline of a city [Vancouver] where nearly half the population is foreign born has prompted widespread anger. For many, the name conjures up the president’s anti-immigrant rhetoric, vows to temporarily ban Muslims from the country and reversal on transgender rights. “We want to push back against this emboldening of hatred and misogyny and xenophobia and racism,” said Mathew Kagis, one of the organisers behind the Trump Welcome Party, a day-long protest being planned.|
Now consider the wording on the Invasive Species Council of BC’s website and replace the word ‘species’ with ‘humans’ and gauge your reaction:
|Have you heard about the harms of invasive species? You can help! Invasive species that enter and establish in British Columbia bring harmful impacts to our environment, economy, and society. You can help to reduce their impacts and make a difference to support healthier communities!
[Richmond News 2016] May the “force” (May 4th) be with the City of Richmond in battling an army of invaders that have come to seek the destruction of Lulu Island’s empire.
The language we use towards plants is often strident, protectionist (native species at all costs) and militaristic. ‘Us’ versus ‘them’. Yet when Trump uses the same attitude, trying to close America’s borders and remove illegal immigrants, people become extremely upset. You may feel that comparing human beings to plants is offensive. Nevertheless, the language we choose to use when discussing both humans and other species is controversial.
No suggestion is made on the BC invasives website about how to reduce the impacts of humanity, the single largest problem. Humanity instead targets specific plants and animals to eradicate and spend billions worldwide trying to deal with species that we moved into a new area, either intentionally or unintentionally. And by now we know how well human intervention works (meaning unintended consequences). Sometimes we choose the opposite by protecting a species that is non-native, or changing our minds about a plant that was once seen as helpful but is now ‘dangerous’.
In his book The New Wild, author Fred Pearce illustrates many examples of how humans try (and fail) to deal with changing ecosystems.
|Pearce acknowledges that there are horror stories about alien species disrupting ecosystems, but most of the time, the tens of thousands of introduced species usually swiftly die out or settle down and become model eco-citizens. The case for keeping out alien species, he finds, looks increasingly flawed.
As Pearce argues, mainstream environmentalists are right that we need a rewilding of the earth, but they are wrong if they imagine that we can achieve that by reengineering ecosystems. Humans have changed the planet too much, and nature never goes backward. But a growing group of scientists is taking a fresh look at how species interact in the wild. According to these new ecologists, we should applaud the dynamism of alien species and the novel ecosystems they create.
In an era of climate change and widespread ecological damage, it is absolutely crucial that we find ways to help nature regenerate. Embracing the new ecology, Pearce shows us, is our best chance. To be an environmentalist in the 21st century means celebrating nature’s wildness and capacity for change.
Is grass used for lawns not invasive simply because we planted it and it doesn’t tend to self-seed? Even though it covers thousands of acres in each city, acts like a monocrop, and displaces plenty of native species?
You’ll find a lot of ‘invasive’ on edges: of roads, railway tracks and riverbanks, where humans have already left their mark. Edges are where biodiversity is the richest, and there are plenty of edges in urban environments. Both humans and plants tend to clump together with their own kind; it’s normal to do so.
The bigger question is whether natives would fill a niche left behind by removed non-natives. One of the reasons we have species like Scotch Broom spreading across cleared areas is that is fixes nitrogen in the soil, stabilizes the soil through its deep roots, and is a pollinating plant. Oh, and we introduced this ‘invasive’ in the first place back in 1850. The argument is made that Scotch Broom “competes with native species for available light, moisture and nutrients, especially on disturbed sites.”[i] That’s because it takes root quickly. The fastest wins. In reality, nature’s traits are transience, dynamism and contingency rather than stability, permanence and predictability, argues Fred Pearce.
We fear that invasives will displace natives (again, uncomfortably like Europeans displacing First Nations people here in BC). Native species are judged as better. Why? Because they evolved here due to circumstances that favoured them. If those circumstances change – such as due to habitat loss and climate change – why are we fighting the plants and animals that move in, rather than questioning our own motives that allowed for those changes in the first place? That’s a huge challenge, so we focus on something we can do: battle the non-natives. Even though virtually everything was an invader at one time, given that this region was covered by glaciers 10,000 years ago.
Perhaps there is some guilt involves? We radically change landscapes and then try to deal with the changes to the urban ecosystems that result. Even when natives succeed, such as animals that come closer to human settlements, such as cougars or bears, we’re not happy with that, either.
In fact, the most diverse ecosystems seem to be forming within our city boundaries:
|The migration of wildlife from back country to downtown is a continental phenomenon, one of the fascinating developments of the 21st century.
Scientists call it “synurbization.” It refers to a growing recognition that cities themselves represent a new evolutionary trend, what one researcher has described as an explosion of new and strange types of artificial environments in the natural landscape to which wildlife adapted over millions of years. A century ago, more than 80% of us lived rural lives, intruders into the habitats of wild creatures. Now, fewer than 15% of British Columbians are rural inhabitants and it’s the wild that intrudes into the domesticated spaces most of us inhabit.[i]
Of course, we don’t battle against honeybees (brought here by Europeans) which we need to pollinate all the non-native plants we grow. 99% of our diet is comprised of genetically altered/ domesticated food sources. We also don’t try to eradicate earthworms, brought by farmers to work the newly tilled, thin forest soils.
When a new species does spread quickly, it can be frightening as the existing ecosystem may be unprepared, causing native species to die off, sometimes up to 90%. This happened in Australia with the spread of the cane toad. But over just a few generations, animals learned not to eat toads (Australian native snakes developed smaller heads so their successors could not swallow them), and the native species have made a come-back.
If you take a walk in the woods, say in Sunnyside Acres in South Surrey, or Green Timbers Urban Forest in North Surrey, there are not all that many species on the forest floor. It’s not that the ecosystem is in perfect balance and harmony, not to be disturbed, but that the current mix of species has worked up until now. When a new species moves in, perhaps shoves some other plants aside, it adds biodiversity and new habitat for other species. We seem particularly alarmed about blackberries and English ivy, to the point where the BC government has debated an Invasive Species Act. But are our fears based on scientific research and published studies? There seem to be far fewer of them around, versus anecdotal comments about how non-natives decrease biodiversity.
This is difficult to discuss, but has to be said: in the past humanity has applied the same attitude about invasive species (undesirables) to our own species.
|Eugenics is a set of beliefs and practices focused on improving the genetic quality of the human population. The American eugenics movement was rooted in the biological determinist ideas of Sir Francis Galton (half cousin of Charles Darwin), which originated in the 1880s. During the ‘Progressive Era’ of the late 19th and early 20th century, eugenics was considered a method of preserving and improving the dominant groups in the population; it is now generally associated with racist and nativist elements as the movement was to some extent a reaction to a change in emigration from Europe rather than scientific genetics. [i]|
Many people are very uncomfortable with the idea of genetic testing, or stem cell research, or humans trying to create a ‘super baby’ through gene selecting. This is in part because of possible unintended consequences. Just because humans can do something, doesn’t mean we should.
We participate in ‘wildcrafting’, harvesting native plants for our own uses, eradicating large patches of plants that local wildlife used to depend on. We change landscapes and local weather (more pavement, less forests in Surrey have made it warmer and drier), causing some botanists to call Western Red Cedars the ‘Western dead cedars’ as they struggle to adapt. How often is it the fault of an invasive species that a native species is at risk of being lost, versus climate change and habitat loss?
It’s worth noting that worldwide, aboriginal peoples have altered landscapes for their own uses, too (in particular clearing land for agricultural uses). Very few cultures have ever lived 100% in balance with nature. The trend towards ‘rewilding’ is also artificial, given that there are no ecosystems that humans have not already altered. Having a national park or nature reserve, fencing off an area and trying to keep the species there static, is rather like creating a museum.
So perhaps it is time to stop thinking of ecosystems as something that needs protecting and stabilizing, and stand back to observe, then interact, with nature as it changes over time. Is the sixth great extinction[i], which biologists say we are in, caused by species spreading to new areas? Does that mean we worry about biodiversity on a global or local scale? Do we remove species from an area, even when natives have come to depend on it?
And how about a multicultural approach to plants? This article makes an interesting point about nature-society hybrids:
|in the late 1980s, I was working as an environmental education adviser in a north London borough. While some of the borough’s schools wanted advice on creating “nature gardens” using native species which they had been told were “better” for wildlife, others wanted advice on creating what I called multicultural or ‘world’ gardens, in which teachers and parents were intentional in selecting plant species from the diverse countries of origin of pupils in the school. These gardens were in effect autotopographies: cultural inscriptions on the school landscape that offered a statement of presence, of recognition, that both humans and nature(s) in cities are increasingly different, diverse and cosmopolitan, and are welcome.|
As always, humans have the capacity to do as much good as harm. We can regenerate areas and observe succession in nature when an area is healing. For example, 40 acres in Green Timbers Urban Forest was cleared in the 1980s. Other than mowing the grasses twice a year (and putting in a lake), the parks staff now leaves the area alone. So you can go for a walk each season and observe the different species that have moved into the space, including lupins to fix nitrogen and the ‘Butterfly bush’ (Buddleja davidii). The BC invasives website notes that “Until only recently, this species was celebrated for its robust growth, fragrance and range of bloom colours, and often recommended for its ability to grow in poor soil and to attract butterflies. Unfortunately, the butterfly bush has escaped cultivation in southern BC and is now considered an invasive species.” We frequently change our mind about what is acceptable and what is not. Perhaps a better word to use is ‘successful’ versus ‘invasive’? If we want to control the spread of a species, ask why it is successful in the first place. It’s great to conserve, and to have some native plants in your garden. But there are many considerations regarding the altered ecosystems where we all live. Maybe we can find a way for us all to live together.