• Olympic: Three Parks in One


    National Park Washington

There are park alerts in effect.
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  • Madison Falls Trail Closed for Repairs Beginning July 7

    The one-tenth mile Madison Falls Trail and trailhead parking lot located in Elwha Valley will close to public entry beginning on Monday, July 7 while crews make improvements and repairs.

  • Hurricane Ridge Road Closed to Vehicles Sunday 8/3 (6:00a - noon)

    Due to the "Ride the Hurricane" bicycle event, the road to Hurricane Ridge will be closed above the Heart o' the Hills entrance station from 6:00a to noon on Sunday August 3rd.

  • Spruce Railroad Trail Improvements to Begin August 5

    Spruce Railroad Trail will be closed from the Lyre River TH to approximately 0.25 miles east of Devil’s Punchbowl. Work is expected to be completed by the end of October. The remainder of the trail will be accessible from the Camp David Jr. Road TH. More »

Nonnative Species

Scot's Broom

Scot's broom, shown flowering here,
is an invasive exotic plant.

NPS Exotic Plant Management Team

A nonnative species is a species that arrives in new habitats as a direct or indirect result of human activities. They are sometimes called “exotic” or “alien” species.

Some species are introduced intentionally (like llamas) and others, like thistles, arrive unintentionally.

For examples of introduced plants,
see Invasive Plants.

Quagga mussels

Quagga mussels, like these at Lake Mead, can negatively impact natural ecosystems.

NPS Photo

Some Nonnatives are Harmful:

Some nonnative species cause no problems, but others can be harmful to native or endangered species, ecosystems, or even human health.


  • Wood-boring beetles and diseases transported in firewood can kill trees. Solution: don’t bring firewood from home, get it locally.
  • Quagga and zebra mussels, freshwater mollusks nonnative to North America, have been traveling throughout the U.S. Since they are often found in the millions once they move to an area, they can easily outcompete native water species. They produce microscopic larvae that pass through screens and clog water treatment systems. Solution: clean off boats, trailers, and equipment before leaving home and when leaving the water so these mussels don't invade Olympic or elsewhere.
Japanese Knotweed

Japanese knotweed showing lack of understory

NPS Exotic Plant Management Team

More than 200 plant species in Olympic National Park are nonnative. About 70 of those species are found within the park’s wilderness. Established nonnative plants can affect natural succession, plant community structure, geophysical processes, and displace or eliminate native species. Some nonnative plants are not a threat, but a few species could cause irreversible impacts such as eliminating rare native species.

For more on nonnative plants with negative impacts, see the Invasive Plants page.

Did You Know?

Mt. Olympus in winter

That Mount Olympus receives over 200 inches of precipitation each year and most of that falls as snow? At 7,980 feet, Mount Olympus is the highest peak in Olympic National Park and has the third largest glacial system in the contiguous U.S.