Invasive Species and Humans: Lessons from nature about building Communities

By Alisa P. Ramakrishnan, PhD

Diversity, communication, and power! My research on invasive plants makes me think that we could learn a thing or two from weeds about building communities and solving problems. Great weeds often come from lots of different places (diversity), then they hybridize with each other (communication), and then they take over (power). We can use those principles to strengthen our own communities. Let me go over a few things about invasive plants to show you what I mean.

Invasive species come to a new place, and then suddenly they take over. Blackberry has done a good job here in BC – you see it everywhere, especially if you’re trying to traipse through overgrown woods. Kentucky bluegrass is another invasive species. You plant your lawn in one spot and it creeps away from you, sneaking into your rose beds and bulbs. It’s everywhere in our nearby pocket forest, beating down the seedlings of native plants that have to struggle through its thick turf to grow.

1 invasive ivy and suchlike

Invasive plants can have difficulty establishing in a new area – they might not have the resources they need, and they often confront new challenges. Most plants introduced to a new area do not survive. The only way to keep those populations alive is to keep adding more and more plants, trying to keep them from dying out.

But every once in awhile (about 10% of the time), something happens. A plant species that has never been in a new area suddenly takes off running and in a few years it seems you can’t get away from it. Scotch broom on the Island, for example. Those yellow flowers are everywhere! What gives?

The grass that I studied (Brachypodium sylvaticum, or false brome) is invasive in Oregon, Washington and California. But not always. New populations often struggle to survive, and plants there grow slowly. Plants in the main source region, though, grow fast and furious, and make so many seeds that it’s easy for them to stick in people’s socks and take the fast road to new horizons and new possibilities. They have the chance to start their own little invasion.

2 false brome

Why do some areas of false brome struggle while others pump out seeds like mad? The answer is integration (“admixture,” in population genetics talk). The areas that drive the whole range expansion are those that have a lot of different plants with different ways of life, all living together, talking, playing, having fun, making babies…oh, sorry, I forgot which species I was discussing. But yes, when genetically different plants get together and make seeds, the grandbaby plants have an astonishing array of traits. Tall, short, big leaves, small leaves, flower early, flower late, germinate immediately, wait to germinate – anyway, you get the idea. (We’re still working out the details on this for false brome but the overall concept is solid.)

Here’s a possible example – when a problem comes along, like a late freeze that kills lots of young seedlings, there are late-germinators waiting in the soil to pop up anyway, and we humans never notice that there was a major challenge in that patch of false brome this year. The areas of grass with lots of different kinds of plants have an easier time surviving and sending out seeds to new populations.

How does this relate to humans? It seems to me that diversity is a good thing. If I were going to use invasive species biology to run a human community, the first thing I’d want is diversity. Diversity can make up for a severe lack of resources, because people from different areas will be able to combine their ideas (assuming they manage to work together) and come up with completely novel solutions to difficult problems.

3 world map

The second thing we’d need is a common language, or at least some really good translators. Everyone has to get the same information in a way they can understand it, and they need the opportunity to contribute their ideas to the community, and to discuss potential solutions together.

They’d also need the power to bring about the solutions they come up with. You can’t take a diverse community, get everyone talking, come up with solutions, and then shut them down. That seems to not be the point, right?

Let’s say a lot of people go to their local government and say, “We like green space, we like parks, we like huge old trees, eagles and animals, and we like to live here.” The government (hopefully representing the people) can guide the process, helping people talk to each other, come up with solutions, and make cities beautiful, or it can shut them down, catering to only a small group of people.

4 houses by south surrey athletic park copy

If the government manages to bring people together and help them communicate to come up with novel solutions, they can create a community where everyone has the resources they need – jobs, houses, green space to run around in, dog parks, natural areas with old trees for birdwatching and all sorts of little creatures and plants, stores in walking distance, everything! But it takes communication and a willingness on all sides to listen.


Let’s take a lesson from invasive plants – let’s talk together, work together, and make things beautiful for everyone.



The opinions expressed in this article are the author’s and are presented here by the GHSA to encourage healthy debate. The GHSA Blog exists as a resource to enable members concerned with the environmental and community stewardship of Grandview Heights to voice perspectives. When directors of the Association contribute to the blog, they do so as private citizens, not as officers representing the Association. The GHSA reserves the right to edit, condense or reject any contribution.