Non-native species – introduce with care!

We tend to get carried away, impressed by our knowledge, while forgetting that what we don’t know is vastly greater than what we do. We introduce non-native species to an area because, in another part of the world, they do something we like. What’s quoted below is from the book “The Vegetarian Myth” by Lierre Keith. She goes into great detail about the lives of plants and this gives us an insight into just how ignorant we are about the intricacies of ecosystems.

We have to understand that the permaculture designs we make are but a pale imitation of the real world; a vastly simplified system designed to provide food for us. We should approach this with humility and care. The quotes within the text are from a book called “The Lost Language of Plants” by Stephen Harrod Buhner.

Buhner talks about archipelagoes of plant communities, groupings of intercommunicating plants around a dominant or keystone species, usually a tree. These archipelagoes form in response to mysterious and unpredictable cues, and often announce the wholesale movement of ecosystems. The process begins with an outrider or pioneer plant, who literally prepares the soil for its cohorts. When the soil is ready, the nurse plant sends out the chemical message: join me. What happens next is astounding. 

Though wind, ants, and burrowing animals may sometimes disperse keystone seeds to the new locations, researchers have found that mere wind and animal dispersal patterns cannot explain how the seeds move. The distances are too far, the dispersal patterns too unusual. But by whatever means, the seeds answer the chemical call sent by the nurse plants.124 

Once established, the keystone plant then calls the bacteria, mycelia, plants, insects, and other animals necessary to build a healthy and resilient community. The keystone’s chemistries arrange the other species and direct their behavior. “This capacity of keystone species to ‘teach’ their plant communities how to act was widely recognized in indigenous and folk taxonomies.”125 Elder trees are called elders for a reason. 

Among many indigenous and folk people it is said that the elder tree ‘teaches the plants what to do and how to grow,’ and that without its presence the local plant community will become confused … Other indigenous peoples, recognizing the nature and function of keystone species, have said that ‘the trees are the teachers of the law.’”126 

The individual plants will not achieve the same growth when in a relationship with a keystone species, but together “they create more biomass than if grown separately, even if supplied with all the water and nutrients they need.”127 They use more CO2, grow denser root systems, create more extensive canopies and hence more photosynthesis, store more water both internally and in the soil, and attract a wider range of soil organisms. Concludes Buhner, “A plant community is far more than the sum of its parts.”128

Not only do trees create rain. They typically use only one-third of the water they lift from the soil for themselves. The other two- thirds are for the tree’s cohorts.129 And it goes beyond water. “Plants always produce more chemistries than they need for their own health: these chemicals are released into plant communities and ecosystems to maintain them.”130 Plant chemistries, air- or soil-borne, affect seed germination, mitochondrial oxygen usage, bacterial respiration and hence growth, plant respiration, and humic acid formation. They literally control life on earth.

Plants may not respond in a way that is obvious to our ambulating species, but they do respond. It’s only that they are moving at a speed that we have to work to understand. Start with the fact that plants can live thousands of years. There’s a 43,000 year old holly in Tasmania, a creosote that is 18,000 years old, a grass colony that’s 1,000.131 This is almost inconceivable to our human timescale. Writes Buhner, 

plants and plant communities possess tremendous powers of movement… their movement shows intention… they can cross thousands of miles when motivated and … their movement patterns are not random but are determined by large-scale feedback loops millions of years old. On a short, localized scale: Climbing plants that need support will grow toward a trellis, and if the trellis is shifted the plants will change direction. On long scales this can be even more pronounced, though it is harder to see… Plants circulate throughout ecosystems, between ecosystems and across and between continents; the longest seed dispersal distance known (without human help) is 15,000 miles. Plants, in fact, move themselves throughout land masses and across distances that mere seed dispersal dynamics and mathematics cannot explain. The places they move to and the ways that they arrange themselves in ecosystems are not accidental and are not random.132 

In the absence of complete understanding of a system, we should mess with it as little as possible.

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