By Annie Bronez, Education & Outreach Specialist, Tualatin SWCD
As part of a regional effort among conservation groups, Tualatin SWCD is working to protect and restore Oregon white oak ecosystems. Since most of the oak habitat that’s left in Washington County is on private lands, participation by residents is critical to this conservation initiative. Although historic oak landscapes are rare today, mature Oregon white oaks are scattered around our communities.
Not sure where to look? Visit these local natural areas:
- West Linn White Oak Savanna
- Henry Hagg Lake at Scoggins Valley Park
- Cooper Mountain Nature Park
- Tualatin River National Wildlife Refuge
How to identify an Oregon White Oak
Look at the leaves…
- In summer, they are dark green on top and pale green underneath.
- In the fall, they turn brown, gold, and sometimes red.
- They have 7 – 9 lobes with rounded edges.
- They grow 3 – 6 inches long.
Look at its shape…
- When alone, its branches grow out wide.
- If near other trees, it grows tall and narrow.
- It can be 30 – 100 feet tall with a trunk 2 – 4 feet around.
- Its grayish brown bark is scaly, and often covered in moss and lichen.
Other clues…
- Acorns appear in the summer. They have a shallow cap and grow to be about 1 inch long.
- Tiny wasps lay their eggs on oak stems and leaves. In response, the tree creates a gall. These speckled round balls have a Styrofoam-like inside and make a popping noise when stepped on.