The Philosophy of Exotic Plants

By on January 23, 2012.

Recently I was asked to discuss  the concept of exotic and native species with a fourth grade class. Being a request from my mother, I shrugged and agreed. The talk should be simple enough right?…. but I’m having second thoughts.

Granted, exotic species can overtake our fragile natural ecosystems, reduce food and habitat for wildlife, and require millions of dollars to control. Native species often  require less maintenance, fertilizer and reduce the sequestration of our natural resources while ensuring the pleasures of wildlife and a healthy, happy ecosystem.

But as a landscape architect, I may specify a 90% non-native landscape for a tropical themed client.  Do I dare explain that one to a 9 yr old? How is that right? Why is that wrong?

The problem seems to be that the general public doesn’t always see the beauty and importance of native plants and may describe them as dull, lacking luster and scraggly.  Sans the beauty of the  sublime, clients prefer year round colors and exciting, unique texture. Our eyes have evolved to prefer this color and contrast.  We even ascribe new colors to our years.  Behold, the warm and encouraging color of 2012.

Pantone Color Institute*

In his book  Botany of Desire, Michael Pollan describes how apples, tulips, marijuana, and potatoes capture the human need for sweetness, beauty, pleasure and sustenance. He asserts the idea that  human domestication has gone hand in hand with plant domestication since the beginning of time. Just like the bee, plants have sought to please our affection to color and scent. Tulip Mania in the 17th century Holland even displays how the quest for ownership of rare tulip varietals  and the social stature associated with it led to a bust much larger than any housing bubble. Yet, we rarely think that a plant can amount to anything important.

Plants do not yet have feet, so they rely on others to expand their territory and range.  Insects help to pollinate their flowers, birds and animals feed on the seeds and plant them in a steamy medium. Soon humans would grow them in fields and trade them across the globe.

We use exotic plants in every aspect of our lives in one way or another, often not being able to live without them.

Some of the analysis here stems from the November 2011 Edition of LAM “Not From Around Here”, where an essay in Nature “Don’t Judge Plants By Their Origins” argued against the demonized notions associated with harsh words like invasive and alien.  The Nature article cites how an invasive Tamarix species once feverishly eradicated now serves as nesting habitat for the endangered southwestern willow flycatcher bird.

I guess my message is…. before the public goes up in arms and ardent community development boards black list all exotic plants, we must understand that embracing and cautiously utilizing exotic plants is a key to our own evolution.

Example: For an efficient and sustainable landscape, exotics may be the backbone of a much needed filtration wetland or  can be a pioneer species in a regenerative, toxic post-industrial landscape. Due to their natural competitiveness, they can be more suitable to arid, saturated or disturbed environments that cannot support historically native plants.

It is imperative to continue habitat preservation, encourage the use of native plantings. Using tools like your local invasive plant list is still valid and highly recommended.

But the philosophical question remains; Who are we to deny life, liberty and the pursuit of happiness to a plant ? A plant that we invited over for purpose of a meal or industrial labor or because it’s pretty to look at? As humans, we have moved our species to every corner of the earth and accomplished some great and horrible things; are plants not just trying to do the same thing?

Finally, as our civilization moves toward a global society, I have no doubt the plant world will  follow. Whether in our nurturing hands or unbeknownst on our trouser cuffs.

Feel free to leave your critical perspective on this topic below on our comment board.


Landscape Architecture Magazine. November 2011

The Journal, Nature. Vol. 474, no. 7350, June 9, 2011