Tualatin Mountains

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The Tualatin Mountains on a satellite image of Portland

The Tualatin Mountains [ twälə tən ] (also West Hills, West Hills or South Portland Hills ) are a chain of hills in Portland, Oregon, United States. You can reach the Cornell Mountain 387 m their greatest height.

Location

The Tualatin Mountains extend over about 20 kilometers northwest -southeast direction on the west bank of the Willamette River and its tributary arm Multnomah in the northwest of Portland. In the West, the broad valley of the Tualatin River, a tributary of the Willamette River extends.

Part of the hill is located within the city of Portland. Politically, the area belongs to the Multnomah County, only the western reaches are located in Washington County.

In the southeast, the area of the hills is already densely populated, about 2000 ha are, however, by the 1948 Forest Park was proclaimed a nature reserve, which today is the largest urban forest in the United States. This part of the hill and the northern sections are heavily forested.

Mountains

• Cornell Mountain, 387 m
• " Portland High Point " ( unnamed highest point in the city limits of Portland ), 360 m
• Council Crest, 323 m
• Pittock Hill, 305 m

Geology

The mountain is of volcanic origin and is mostly built of Columbia Plateau basalt and rocks of the Boring lava field. The rock is eclipsed by a loess layer, consisting mainly of Pleistocene silt. This layer, which has largely deposited during the Missoula Floods 13,000 and 15,000 years ago, is very unstable especially when wet and is prone to landslides.

Fauna and Flora

The natural vegetation of the area is characterized mainly by the American West Hemlock. In addition, Douglas fir and the giant tree of life are decisive. Due to the forestry, natural vegetation, however, was changed, so that today hardwoods such as red alder and Oregon maple are relatively common to find. The forests have dense undergrowth.

With easy access to the natural ecosystems to the northwest, the Forest Park for a city forest on a high biodiversity. To penetrate here with coyotes, bobcats and mule deer even black bears and cougars in the immediate vicinity of the city before. The preservation of these compounds is seen today as the most important condition for the preservation of the fauna of the Tualatin Mountains.

History

The name of the mountain derives from here once settled people of the Tualatin (also called Atfalati ), a northern group of the Kalapuya. The original meaning of the word Tualatin is not known.

For the European settlers were the steep and densely forested mountains of little value in comparison to the vast fertile plains in its west, which were later used to about 1840 mainly English as pasture for cattle farmers growing wheat.

As a result of the Donation Land Claim Act (1850 ) the area was divided in 1851 among white settlers. Due to the small value, a large part of the substrate was not used. As a result, fell into disrepair claims and many plots were bequeathed to the city. This and the unstable geological conditions contributed much to the preservation of the natural state in this area in as many construction projects have been prevented by the unreliable underground. Moreover, it was already started here around 1900 so that to preserve the forests of the Tualatin Mountains, through the establishment of the first protected areas from development and to get as close to nature recreation area.