Oregon’s mysterious tidal forests

A sneak preview of Laura Brophy's upcoming pub talk, Pelican Pub, Pacific City, Oregon, 6-8 pm on March 12, 2020

By Laura Brophy

February 2020

Oregon's estuaries today are full of beauty: salt marshes with intricate, winding channels and mud flats with wheeling flocks of shorebirds and clam beds for the adventurous forager. But did you know that in pioneer times, over half of the Oregon coast's tidal wetlands were forested tidal swamps? A recent study completed by the Estuary Technical Group maps these historic tidal swamps and their current distribution. You can download the report here: https://bit.ly/3bSnD7S

These magnificent tidal forests of the Oregon coast, dominated by salt-tolerant Sitka spruce (Picea sitchensis), contain deep tidal channels that shelter young salmon on their way to the sea, providing abundant food and protection from predators and high river flows.

Sitka spruce tidal forest in the Yaquina Bay estuary

Per acre, these tidal swamps store more carbon than almost any other ecosystem on earth -- in their soil, their dense vegetation, and the elevated root platforms of the Sitka spruce.

Sitka spruce tidal forest in the Youngs Bay estuary

But since settlement times, 95% of these tidal forests have been logged and converted to farmland, so we've lost most of the wetland functions they once provided.

Diked pasture in the Siuslaw River Estuary. Before diking, this was a tidal forested wetland.

However, the recent study also found encouraging news: over 1770 hectares of new tidal marsh have formed on the Oregon coast since the mid-1800s, and there's been very little erosion or "drowning" of tidal wetlands – unlike many other parts of the country.

Today, we're working hard to learn about the physical and biological conditions in Oregon's tidal forests, and how to restore them. Innovative restoration methods like nurse logs, log "cribs", and soil mounds help give planted saplings a "head start" and may also assist sea level rise adaptation.

Planting young Sitka spruce in log "cribs", Coquille River estuary (photo courtesy of Jake Robinson)

In a fun pub talk at 6 pm on March 12, 2020 at the Pelican Brewing Company in Pacific City, Oregon, Estuary Technical Group director Laura Brophy will share more surprising facts about these long-lost tidal forests and what you can do to help bring them back. Click here for a flyer about this event!

Posted in Estuary Technical Group and tagged , , , .