The Downside of Using Alien Plants--Wildlife Habitat Loss

I'm not talking about Triffids here, but instead the large percentage of plants we use in our landscapes. Most plants used in landscapes are not indigenous to the site where they live out their lives. Non-natives from around the world have been collected and primped to become the darlings of the landscape fashion world. There are beauty contests to determine the most exquisite rose, the purplest pansy, and the reddest maple. Our landscapes have been severed from their original natural functions--cleaning water, making oxygen, moderating climate, decomposing waste, and providing habitat for the animals that are part of the web of life.

It turns out that insects (and all those other creepy things I'd like to all call insects), including soil organisms, are mostly picky eaters. Ninety per cent of herbivores are specialists, meaning they can only eat what they evolved to eat. Ten per cent are generalists, allowing them to eat multiple different species of plants they evolved to eat. Of that 10% only a few species are able to adapt to alien plants. So in a landscape there are fewer pests initially--in terms of numbers of different species and, because nearly all the native insects,et al, have flown the coop, looking for each one's (or two or three) true love--the plant of its true desire.

The longer a plant has been in the trade though, the larger the chance that someone (other than humans) will find it attractive. Either a hitchhiker from the plant's native habitat arrives to rejoin its true love or some other wildlife is able to adapt to the new culinary fare. There are many tales of woe when a plant or animal gets transplanted to another habitat and gets an upper hand or causes some unexpected consequence. Hawaii, because of its isolation from other ecosystems is a classic example of how nature twists and turns in its effort to find balance. The Galapagos Islands--Darwin's laboratory for his Origin of the Species is another case in point. Add your favorite ecosystem destruction story in the comments section below.