Mission Statement

Bearing Witness to Local Natural History-- from the wildness of Indiana

Saturday, June 18, 2011

Invasive Plants: Are They Really a Problem?

In the last several years a new battle has been waged on plants that are considered invasive to our landscapes. The premise is that identified non-native plants when planted or not controlled, can over-populate and over-run our native plants.

                                                        Copyright Joni L. James
                                                        Great Spangled Fritillary on Coneflower                                                                                     

I finished reading an article titled "A Friend to Aliens" in Scientific American (February 2011) by Brendan Borrell. Borrell interviewed plant ecologist Mark A. Davis (Invasion Biology 2009). Davis at one time felt the same about invasive plants until he began re-thinking his stance. He now believes we should be concerned about invasive species only when they can impact economics or be a direct threat to health. According to Davis we must understand that species do not stay put and accept this.

He argues that a species is a problem only when humans deem it so-- they aren't good or bad. We have to ask if a species is causing harm or is it just representative of change.

He does state that when species cause extinctions, especially in insular environments, action must be taken. He goes on to say that they have conducted field experiments with garlic mustard (a prolific "invasive") and found no relationship between the abundance of garlic mustard and the population of other plant species in their field plots.

This was an interesting article and it caused me to think on the topic of invasive plants in a new light. I don't profess to be a plant expert or to truly take a stance on the subject. I merely present this information as an opportunity for readers to think about this issue and perhaps learn more.

No doubt non-native species can have a devastating impact on our local landscapes and the organisms that live there. I believe in planting and nurturing native plants as often as possible. But perhaps somewhere in the middle is the starting point. Perhaps each unique situation must be evaluated as to how an ecosystem/area might be impacted and how species--native and non-native may interact.

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