• View from Sourdough Mountain Overlook  A view looking down onto Diablo Lake. Photo Credit: NPS/Michael Silverman, 2010.

    North Cascades

    National Park Washington

Nonnative Species

The North Cascades are witness to an epic struggle. On one side are native plants such as vine maple, bracken fern, and thimbleberry which have made their home in this ecosystem for thousands of years, adapting to thrive in this unique climate and terrain. On the other side are non-native plants such as English ivy, scotch broom, and spotted knapweed which have settled into this ecosystem within the last two hundred years. The non-natives are looking to displace the natives and claim the habitat as their own.

Many non-native plants were introduced to the North Cascades ecosystem by humans seeking to beautify areas or to revegetate disturbed land resulting from construction projects. Others were introduced by accident, brought in as seeds attached to vehicles, animals, and cargo. Whether valued for their beauty or for their rapid growth, these non-natives have been successful in their new environment and threaten to completely displace the ecosystem’s original inhabitants.

What will the future look like? The natives will reclaim the habitat lost to the non-natives. This is, if resource managers at North Cascades National Park Complex get their way. Non-native species are sought out and eradicated through a variety of techniques. Some plants are removed by hand; others are attacked by biological controls, insects that eat plant-specific seeds. Even herbicides are being used where necessary as a last resort to give the natives the upper hand in their struggle against the non-natives.

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