|Gorse at the Oregon Coast|
Many invasive species are beautiful to look at. Think of the vibrant green foliage of English ivy, the lovely flowers of blooming yellow star thistle or the striking mustard color of gorse set against an ocean backdrop. And yet invasive plants and animals rival climate change and habitat destruction as the biggest threats to Oregon's environment. Part of their success lies in the fact that our sense of what's beautiful often trumps our understanding of what's native and natural. Green grass is better than mud, right? Not so in the case of invasive spartina. And those mesmerizing flocks of starlings? Not so great when you're a farmer trying to save a crop from being devoured by these invaders.
Understanding the threat invasive species pose to our native plants and wildlife requires thinking about beauty in new ways. Green isn't always good. Colorful flowers are a poor indicator of landscape health. Understanding invasive species also means restoring "native common sense"— knowing what belongs and doesn't belong in the places we live, even if what belongs may not be as 'showy' as the invaders fighting to take over.
Spartina is one of those beautiful invaders that's so successful because it looks like it belongs. Green fields of waving grass in Willapa Bay look natural, but what native birds, fish and wildlife need is mud. Plain, simple, gooey, mud. It all has to do with what they grew up with. Along the east coast of the United states, shorebirds are perfectly adapted to feeding within dense stands of native spartina (spartina alternaflora). But along the west coast, shorebirds that use places like Willapa and Humbolt Bay feed on the insects and crustaceans that live in wide open and grass free mudflats. When this east coast shoregrass showed up, the birds journeying on a long, difficult migration struggled to find food because the natural mudflats were overrun with grass. So next time you're in Willapa remember—mud good, grass bad.
Timeline compiled from research provided by Friends of Willapa Bay, Washington Dept. of Natural Resources, Willapa National Wildlife Refuge, and from Kim Patten at the Washington State University.
|Crews apply herbicides to spartina during
the height of the counterattack against spartina
in Willapa Bay, Washington.
One of the only known infestations of Spartina in Oregon so far is on the Nature Conservancy's Cox Island preserve along the Siuslaw river. The invader is Spartina patens, a slightly different variety of cordgrass than the Spartina alternaflora found at Willapa. It's invasive just the same. Fortunately, when Nature Conservancy crews detected the invader, they acted. Crews used a non-chemical approach to killing the grass. They covered it up with thick black fabric, cutting off all sunlight and preventing its growth and spread. It seems to have worked. With spartina, as with all invasive species, early detection is the key to reducing the potential for ecological and economic damage.