Paleontology Field Opportunity for OAS members

There is a fascinating site area 30 miles south of Portland. It is ancient, far more than 10,000 years old.  Contained within it is amazing evidence of times’ past.  This resource is a record of the occupants of the Willamette Valley, from 15,500 to 10,500.  It is also a record of dramatic environmental change.  Thought provoking is an understatement!

Many giant animals, termed megafauna, lived at Woodburn during the last Ice Age. The remains of these four species have been documented at this site.


In July and in August, a limited number of Oregon Archaeology Society members will join IAS staff, in an opportunity to trowel through the soils of two known paleontological sites.  From July 10-15, and from August 14-20, we will be exploring two different site areas.  Both sites are in a locale known to contain numerous extinct, huge animals (figure 1).  These include the giant bison (Bison antiquus), giant ground sloth (Paramylodon harlani), western horse (Equus occidentalis), and western camel (Camelops hesternus).  Some predator species in the area include the Pleistocene bear that became the black bear (Ursus americanus), dire wolf (Canis dirus), coyote (Canis latrans), and a huge predator bird with a 12’-14’ wingspan (Teratornis woodburnensis).  Also at this site are the remains of extant species, including rabbit, muskrat, beaver, gopher, turtle, snake, deer, elk, and five other species of bird.

Microscopic inspection of wood (L) helps to identify species, and the magnification of seeds (R) helps to speciate and to look for gnawing marks. Cherry seed photo provided by David Ellingson.

While the recovery of animal bone, mammalian hair, and the occasional lost cultural item are not frequent, nearly everyone recovers something.  After troweling through blocks of ancient soils, volunteers water screen the sediments.  This allows us to find specimens that were previously hidden within clumps of soil.  Some recovered items are then examined microscopically, helping us to better identify each object (figure 2).

The different layers, or strata, reflect the many different ecosystems that have existed here over the last 16 millennia.  Clearly seen are an ancient forest, stratified peat bogs, loamy soil interludes, and flood silts.  Every year, volunteers are stunned by the dramatic changes that have occurred within a single place on the landscape, and by the preservation of even small seeds and ancient leaves.

Every stratum, or layer of soil, has a different color and consistency, which can be easily recognized.

Every stratum, or layer of soil, has a different color and consistency, which can be easily recognized (figure 3).  The characteristics of each stratum have been documented, and each stratum has been dated.  Thus, when volunteers excavate the blocks of sediments, the approximate age of recovered specimens is immediately known by the stratum from which items emerge.  Beyond the actual recovery, it is simply exciting to be examining the soils as they existed more than 11,500 years ago.

OAS members won’t have to travel far from home, as we will again be at Woodburn.  If you are interested in being one of the 8-10 OAS volunteers, please contact Alison Stenger, of the Institute for Archaeological Studies.  Email, or call 503-292-5862.  Be sure to check the Institute for Archaeological Studies website for a list of what to bring, and also to see pictures of past projects.  This is a wonderful opportunity to learn archaeological methods while investigating a paleontological site.  All tools, training, and laboratory supplies will be provided, but please bring a pair of clean kitchen (rubber) gloves.  There is no fee, although a voluntary $20.00 donation is appreciated, to help offset expenses.

Start dates for newcomers will be a day later than for people with experience at these sites.  Thus, those new to the Woodburn projects will start July 11 or August 15. This will give experienced personnel an opportunity to get the area prepared and ready for new volunteers.  Those previously involved should, if possible, plan to help with site preparation on July 10 or August 14.