Erratic Rock State Natural Site
Encyclopedia
Erratic Rock State Natural Site is a state park
in the Willamette Valley
of Oregon
, United States
. Featuring a 40 short tons (36 LT) glacial erratic
from the Missoula floods
, the small park sits atop a foothill of the Northern Oregon Coast Range
in Yamhill County
between Sheridan
and McMinnville
off Oregon Route 18. The day use only park is owned and maintained by the Oregon Parks and Recreation Department
.
began in western Montana
fifteen to twenty-thousand years ago. These large floods altered the landscape of the Columbia River valley and flooded the Willamette Valley. Many rocks were transported down the Columbia encased in icebergs and deposited from Montana through Idaho
, Washington, and Oregon when the flood waters receded and the ice melted.
One of these 40 short tons (36 LT) erratics was deposited on a 250 feet (76 m) tall hill in the Yamhill Valley portion of the Willamette Valley. Purchased from the Duerst and Ramsby families in 1956, the park was originally named the Erratic Rock Wayside. In 1996, the park was one of the state parks selected for closure due to budget problems. The Oregon Legislative Assembly
came-up with funding to avoid the closure. The park received a new historical marker along the road in June 2005 in a ceremony featuring state senator Gary George.
to the west and McMinnville
to the east. Geologically, the rock comes from Canada
and is the largest glacial erratic rock in the Willamette Valley. The rock is argillite
believed to be 600 million years old and originally part of the sea-floor. It is also the only rock of its type outside of Canada.
In addition to the boulder, the hilltop features views of the Oregon Coast Range
and the valley, including vineyards
and farms. There is a 0.2 miles (321.9 m) hike along a paved trail to the top of the hill past a vineyard and orchard that provides bird watching opportunities. Operated by the state parks department, the park is a day use only facility that includes an interpretive sign and picnic table at the 4.4 acres (2 ha) park.
State park
State parks are parks or other protected areas managed at the federated state level within those nations which use "state" as a political subdivision. State parks are typically established by a state to preserve a location on account of its natural beauty, historic interest, or recreational...
in the Willamette Valley
Willamette Valley
The Willamette Valley is the most populated region in the state of Oregon of the United States. Located in the state's northwest, the region is surrounded by tall mountain ranges to the east, west and south and the valley's floor is broad, flat and fertile because of Ice Age conditions...
of Oregon
Oregon
Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...
, United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. Featuring a 40 short tons (36 LT) glacial erratic
Glacial erratic
A glacial erratic is a piece of rock that differs from the size and type of rock native to the area in which it rests. "Erratics" take their name from the Latin word errare, and are carried by glacial ice, often over distances of hundreds of kilometres...
from the Missoula floods
Missoula Floods
The Missoula Floods refer to the cataclysmic floods that swept periodically across eastern Washington and down the Columbia River Gorge at the end of the last ice age. The glacial flood events have been researched since the 1920s...
, the small park sits atop a foothill of the Northern Oregon Coast Range
Northern Oregon Coast Range
The Northern Oregon Coast Range is the northern section of the Oregon Coast Range, in the Pacific Coast Ranges physiographic region, located in the northwest portion of the state of Oregon, United States. This section of the mountain range, part of the Pacific Coast Ranges, contains peaks as high...
in Yamhill County
Yamhill County, Oregon
-National protected areas:*Siuslaw National Forest *Tualatin River National Wildlife Refuge -Demographics:As of the census of 2000, there were 84,992 people, 28,732 households, and 21,376 families residing in the county. The population density was 119 people per square mile . There were 30,270...
between Sheridan
Sheridan, Oregon
Sheridan is a city in Yamhill County, Oregon, United States. Platted in the 1860s when it received a post office, the city was incorporated in 1880. A major fire burned much of the city in 1913, and a flood covered much of the city in 1964...
and McMinnville
McMinnville, Oregon
McMinnville is the county seat and largest city of Yamhill County, Oregon, United States. According to Oregon Geographic Names, it was named by its founder, William T. Newby , an early immigrant on the Oregon Trail, for his hometown of McMinnville, Tennessee...
off Oregon Route 18. The day use only park is owned and maintained by the Oregon Parks and Recreation Department
Oregon Parks and Recreation Department
The Oregon Parks and Recreation Department , officially known as the State Parks and Recreation Department, is the government agency of the U.S. state of Oregon which operates its system of state parks...
.
History
The pre-historic Missoula floodsMissoula Floods
The Missoula Floods refer to the cataclysmic floods that swept periodically across eastern Washington and down the Columbia River Gorge at the end of the last ice age. The glacial flood events have been researched since the 1920s...
began in western Montana
Montana
Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...
fifteen to twenty-thousand years ago. These large floods altered the landscape of the Columbia River valley and flooded the Willamette Valley. Many rocks were transported down the Columbia encased in icebergs and deposited from Montana through Idaho
Idaho
Idaho is a state in the Rocky Mountain area of the United States. The state's largest city and capital is Boise. Residents are called "Idahoans". Idaho was admitted to the Union on July 3, 1890, as the 43rd state....
, Washington, and Oregon when the flood waters receded and the ice melted.
One of these 40 short tons (36 LT) erratics was deposited on a 250 feet (76 m) tall hill in the Yamhill Valley portion of the Willamette Valley. Purchased from the Duerst and Ramsby families in 1956, the park was originally named the Erratic Rock Wayside. In 1996, the park was one of the state parks selected for closure due to budget problems. The Oregon Legislative Assembly
Oregon Legislative Assembly
The Oregon Legislative Assembly is the state legislature for the U.S. state of Oregon. The Legislative Assembly is bicameral, consisting of an upper and lower house: the Senate, whose 30 members are elected to serve four-year terms; and the House of Representatives, with 60 members elected to...
came-up with funding to avoid the closure. The park received a new historical marker along the road in June 2005 in a ceremony featuring state senator Gary George.
Details
Located off Oregon 18, Erratic Rock State Natural Site lies mid-way between SheridanSheridan, Oregon
Sheridan is a city in Yamhill County, Oregon, United States. Platted in the 1860s when it received a post office, the city was incorporated in 1880. A major fire burned much of the city in 1913, and a flood covered much of the city in 1964...
to the west and McMinnville
McMinnville, Oregon
McMinnville is the county seat and largest city of Yamhill County, Oregon, United States. According to Oregon Geographic Names, it was named by its founder, William T. Newby , an early immigrant on the Oregon Trail, for his hometown of McMinnville, Tennessee...
to the east. Geologically, the rock comes from Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
and is the largest glacial erratic rock in the Willamette Valley. The rock is argillite
Argillite
An argillite is a fine-grained sedimentary rock composed predominantly of indurated clay particles. Argillaceous rocks are basically lithified muds and oozes. They contain variable amounts of silt-sized particles. The argillites grade into shale when the fissile layering typical of shale is...
believed to be 600 million years old and originally part of the sea-floor. It is also the only rock of its type outside of Canada.
In addition to the boulder, the hilltop features views of the Oregon Coast Range
Oregon Coast Range
The Oregon Coast Range, often called simply the Coast Range and sometimes the Pacific Coast Range, is a mountain range, in the Pacific Coast Ranges physiographic region, in the U.S. state of Oregon along the Pacific Ocean...
and the valley, including vineyards
Willamette Valley AVA
The Willamette Valley AVA , is an American Viticultural Area which lies in the Willamette Valley of Oregon. The AVA is the wine growing region which encompasses the drainage basin of the Willamette River...
and farms. There is a 0.2 miles (321.9 m) hike along a paved trail to the top of the hill past a vineyard and orchard that provides bird watching opportunities. Operated by the state parks department, the park is a day use only facility that includes an interpretive sign and picnic table at the 4.4 acres (2 ha) park.