View toward the southwest from Chehalem Ridge toward Wapato Lakes. Taken through a small clearing in a dense forest; a bicycle leans against some sawn logs in the foreground

Chehalem Ridge/Iowa Hill

Published 2023-07-05

At least 10 years ago — probably pre-kids and certainly pre-Strava — I heard a rumor that the oldest Oregon white oak (in the world?) lived at the top of Iowa Hill in the Chehalem hills (between the Tualatin Valley and Newberg). The actual top of Iowa Hill was at that time on private land, in a farmed forest of Douglas firs. One day I rode out that way, up Dixon Mill Road, and timidly jumped a gate onto the private road leading into the forest. I didn’t go very far up the road (timid) but it seemed unpromising anyway. Only a few hundred feet away from the road I was swallowed up by an eerily dark and silent wood of close-packed, evenly-spaced young Douglas firs. There were no other living things but me and the firs.

A glimpse of what the farmed forest once looked like throughout

Fast-forward to 2016 and Oregon Metro (a regional government body) purchased the forest, and over the next five years rehabilitated it into a nature park. From the start I offered feedback and testimony to allow bike access to the trails on the park. (Metro for some reason is more receptive than most local governments to such feedback.)

Yesterday I rode out to Chehalem Ridge and tried out those trails. The ride out was glorious, not too hot and it felt effortless (it turned out I had the wind at my back as I discovered 2 hours later on the return…) My route into the Chehalem region is along Scholls Ferry road, but I tried a new (and much less trafficked) route south of the Tualatin River to Cooper Mountain. Development is moving rapidly west of Progress Ridge which bums me out on a personal level; I especially miss the oak grove at the intersection of Tile Flat and Scholls Ferry Roads.

Wheat field on Firdale Road

An enormous madrone tree standing alone on Firdale road

Similarly, I was a little bummed that most of Firdale and Dixon Mills Roads are now paved. Twenty years ago the only paved roads on the Chehalem hills were Bald Peak Road and Hillsboro Highway.

Where the pavement ends on Dixon Mill Road

As for the park itself: Metro has done a fine job. They have thinned some of the forest to varying degrees. In places it’s still quite dense with young trees. In others it has an open understory that feels very much like a natural forest.

A once-farmed forest thinned to an open understory

In a few places they have cleared it almost entirely to make a series of meadows.

An expertly-constructed meadow in the formerly farmed forest of Chehalem Ridge

In the July heat the forest had a wonderful resinous smell.

There is a large parking lot — it was nearly empty yesterday, which surprised me — with water, bathrooms, and picnic areas.

I can’t remember the last time we had this much green on July 4. Not since the 2000s, probably.

The inner trails are graveled and graded and non-technical; you could do them on a beach cruiser or ten-speed. The outer trails get progressively narrower and steeper; I was fine with 38mm gravel tires on a ’cross bike. The farthest trail is out-and-back to a grove of madrones. The “out” is all downhill and the “back” is all uphill.

The Iowa Hill Oak is in a large meadow at the end of the Mampaɬ trail with a commanding view to the south/west over Wapato Lake. If this meadow were here in 2009 (or whenever) then I must have turned back just before reaching it. It’s also possible that it was crowded in by Douglas firs and I simply never saw it.

Sculpture on Iowa Hill, at the end of the Mampaɬ trail

The tree itself is not especially remarkable, I have seen much larger and gnarlier Oregon oaks. It is clearly a special tree — Metro has built the area around it such that it stands alone, and you can circle around it, but you can’t easily reach it.

The Iowa Hill Oak

On the return trip I came around the Fern Hill/Blooming byway, apparently some kind of “scenic bikeway?” Not too many cars but by now it was noon, 100°F on the pavement, and riding directly into the east wind. I wended my way back to Farmington Road (another fine farm road that in the last 20 years has been swallowed up by traffic and suburbanization). I tried a new bypass over Cooper Mountain but my legs hated it.

Clover fields and bee hives near Fern Hill, looking back toward the Chehalem hills


I dug a little into the World Imagery Wayback and found a satellite photo dating to 2014. No wonder this tree is so small…and why I couldn’t find it umpteen years ago! It was packed in with a zillion farmed Douglas firs.

Also: I can’t figure out how I heard that this tree is the “oldest Oregon white oak.” It’s probably lore I absorbed from the Ancient Internet (pre-2003), or perhaps from a book or magazine? I can find no particular reference now to this particular tree as anything special.

Satellite photo from 2014. The Iowa Hill Oak is circled:

Aerial photo of Iowa Hill, 2014. The Iowa Hill Oak is circled. It is surrounded by a tightly packed forest of tiny doug firs planted in unnaturally straight rows

First Satellite photo taken after the area around the oak was cleared, sometime between 2014 and 2018:

Aerial photo of Iowa Hill, 2018. The hillside around the Iowa Hill Oak has been cleared, some of the farmed trees have been trimmed, and small clearings have been opened in the forest

Recent (June 2023) satellite photo showing the paths and other improvements around the tree:

Aerial photo of Iowa Hill, 2023. The Iowa Hill Oak is distinct in the center of a large meadow, with a path looping around it. A circular stone feature and other improvements like horse tie-offs and bike racks are visible nearby