We engage the imagination, expand knowledge, and empower the environment starting where people live.  We build the community working for the ecological resilience of oaks and the oak savanna ecosystem in the peri-urban interface of the Pudding River watershed and beyond. 

Connecting residents to the history of Silverton's savanna oaks and the role these trees have played in the ecosystem here makes their existence now and in the future meaningful.  Oaks are now too often the only part remaining of once vibrant prairies. It doesn't have to remain that way. We can regenerate prairies with native grasses, perennials and annuals, anchored by oaks. 

Savanna form oaks are the broad, round-headed trees that had their formative years of growth in a prairie where there was no competition for sunlight. They grew as wide as tall. Their trunk grows very thick and they can live for more than 400 years.

The large savanna form oaks now growing in Silverton all started in burnt prairies; they predate settlement. In fact, it is very easy to look at oaks growing now and estimate their age not by their size but by the form and the density they grow in. The oak woodlands we see today around Silverton only began growing after the practice of prairie burning was stopped by the settlers. And this is one of our problems now: it is common for oak seedlings to emerge. But they are very often misplaced, crowded, grazed by deer, or irrigated. Without planning, none of them will grow in savanna form to replace the aging savanna form trees.

In the Willamette Valley less than 3% of preconquest oak habit remains. Savanna form oaks are the low branched and wide growing oaks we still see occasionally. They grew into this from rather than tall and narrow trees because they had access to all the sunlight they could use, with no competition from other trees.

The Kalapuya tribes practiced a form of agriculture unrecognizable to the conquering settlers in the 1830 and 1840’s; dried vegetation, young trees and shrubs were all burned in late summer. These fires were frequent enough to keep camas gardens productive and open profitable hunting grounds while they kill trees that might have competed with the favored oaks.

Oregon white oak, Quercus garryana, is the only oak native in the Willamette Valley. Its range extends from central California, north into southern British Columbia, where it's known by the name Garry oak. 
Like most oaks, it is a light dependent species, and it will not grow in the shade.  Douglas firs grow much faster and taller and are more shade tolerant. It's common to see them crowding into oak canopies. This leads to the death of the oak over time. 

Oak trees have been called the most important trees in our environment because they host so many other life forms - from birds, squirrels, raccoons, to hundreds of insects, pollinators, and countless fungi, bacteria, and lichens. Each tree is like a city unto itself.  Add to all that the benefits provided to the urban forest, like shade, slowed water runoff, economic value, boosted mental and physical health, to name but a few.

We suffer from more air pollution than we like to admit in Silverton. Many days have agricultural soot and forest fire smoke gets worse each year. Leafy trees remove a lot of particle pollution from the air that otherwise can get lodged deep in our lungs causing cancers, lung disease, and cardiovascular problems. Knowing that on smoky day is enough to make us all want to plant a forest! Oaks grow large here and have many leaves. The small particles of pollution (PM2.5) floating in the air collide with the leaves. Much of it get stuck there. Large trees can trap and remove pounds of pollutants each year. 

Cool temperatures in this spot brought to by the shade of the surrounding trees.

Summer’s heat is pleasant in the shade of a tree. The larger the tree the more shade it casts. Areas without shade are much hotter, often dangerously so – hundreds of people died across the PNW during the heat dome of 2021. Not only do trees ameliorate the uncomfortableness of today’s heat, but they also help buffer against too much heat in the future.

The wood trees build themselves out of is about 50% carbon.  An average 25-year-old tree pulls about 40 pounds of carbon from the air each year, locking it into the wood of the tree until the wood burns or decomposes. It is a great long-term solution to too much atmospheric carbon. It is why scientists say planting billions of trees around the world is an important part of slowing climate change.