“Spring wildflowers carpet Mima Mounds National Area Preserve.”
Photo credit: Washington State DNR

“A new twist on an old mystery may finally settle the debate over the origin of Mima mounds, which bulge out of the ground like enormous, grass-covered bubble wrap in western Washington.

Mima mounds (sounds like dime-a) were named in 1841, when a vast pimply prairie (the Mima Prairie) was discovered in western Washington during the United States Exploring Expedition. In the centuries since, the source of this strange landscape has defied explanation. A single field may be covered in a million mounds that are several thousand years old, yet no builder has ever been found.”

“Now, a study analyzing the interplay between gopher and ground vindicates the humble rodent,” quoting Live Science.
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– UPDATE: January 4,. 2014
“Virtual gophers dig up Mima mounds mystery”
“Local scientists put the brakes on California geologists theory”
By Craig Sailor in The Olympian
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