07 October 2009

The Loosestrife Drama

One of my goals in ths project is to present information from hard-core academic literature in simple, everyday language. So it is my great pleasure to present to you today the great Loosestrife debate, as a play, in one act.

Rawinski and Malecki (1984):  Purple Loosestrife is taking over! AHHH!! STOP IT!!! HORRIBLE PURPLE WEED!!!!

Government, environmental groups, people in general: Dude! It is purple and evil! (run about trying to kill purple loosestrife. Spend tons of money. Introduce non-native beetles to eat it. Generally go nuts.)

Hager and McCoy (1998):  Umm... People? Have you actually READ Rawinski and Malecki's paper? It sucks. Basically, they just decided to hate on loosestrife because it is so purple and they noticed it everywhere.

Government, environmental groups, people in general: Lalalalala! I can't HEAR you! (keep spending lots of money trying to kill purple loosestrife)

Anderson (1995), Farnsworth and Ellis (2001), Houlan and Findlay (2004) : (Do a lot of actual research to see if loosestrife is hurting anything) Um... People? Like, Hager and McCoy were right, this loosestrife stuff doesn't seem to be that big of a deal. It just sits there being purple.

Government, environmental groups, people in general: Lalalala! I can't HEAR you! (keep spending lots of money trying to kill loosestrife)

Okay, so I'm being silly, but I started reading about purple loose strife because I wanted to use it as an example of what, exactly, invasive plants do to native species in areas they invade. Surprisingly (to me anyway), in the case of purple loosestrife, the answer seems to be... just about nothing. That's not the whole story – many other invasive species do a lot of damage (more about that in a future post) but it is shocking that so much money and time has been invested in killing purple loosestrife without good evidence that it is worth it. No less than three non-native species of insects have been introduced to the US just to eat the loosestrife. And what if those beetles start eating some other native plant as well?
The lesson I'm taking away from this is: While no invasive plant is good, many aren't all that damaging, and we need to make sure we invest the limited resources we have to save the environment on the issues and species that matter the most -- not just the ones which are easy to notice because they have bright purple flowers.

(Photo: from Urtica on flickr.)

3 comments:

Wm Jas Tychonievich said...

"Basically, they just decided to hate on loosestrife because it is so purple"

Makes sense to me.

As for this great idea of dealing with a non-native plant species (presumed harmful) by importing three non-native insect species (presumed harmless) -- um, yeah. I'm sure nothing could go wrong there. (In other news, experts agree giant, razor-clawed bioengineered crabs pose no threat.)

Garden@93 said...

Joseph, I photographed purple loosestrife on OSU campus recently growing along the river and a tributary. It does spread and can overcome native vegetation. It's on the top ten list of OH invasive plants @ http://www.dnr.state.oh.us/tabid/2005/Default.aspx Introducing non-native insects could present a problem in itself. Check out:http://wiki.bugwood.org/Lythrum_salicaria

Greensparrow said...

No one is arguing that purple loosestrife doesn't spread into native wetland areas -- the problem is there is no evidence that it does any harm to native wetland species once it is there. Which, as you say, makes the introduction of non-native species to control it even more questionable.