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Cedar Mill News
Volume 4, Issue 8


August 2006

Willow Creek Flora and Fauna

By Bruce Bartlett, Bonny Slope resident

I live at the headwaters of Willow Creek. Up here in the Bonny Slope area, Willow Creek is a seasonal creek which dries up in the summer. Willow Creek eventually flows into Rock Creek and then into the Tualatin River. Recently the Rock Creek Watershed Partners started a tour of Willow Creek in my backyard.

Water from the subdivision next door drains through a water-quality vault directly into the Willow Creek headwaters. Marsh buttercup makes the site more attractive while the roots will filter the water and the leaves provide cooling shade.

When I first explored the three acres I eventually bought, it was a wonderful tangle of second-growth woodlands. This wild area was very inspiring and I tried to minimize the impact I had on the property while building a house on it. This meant leaving many of the firs and cedars standing.

The garden beds incorporated the existing native plants: Oregon Grape, mallow, blue-eyed grass, mimulus, snowberry, cascara, vine maple, service berry, sword ferns and trilliums. Very little use of herbicides and no use of pesticides has been made. Herbicides were used initially to control the invasive non-native plants and poison oak.

The back part of my yard consists of a meadow surrounded by oak trees with Willow Creek running through it. Around the creek bed is a camas field (Camassia quamash - The camas was here when I bought the property and I have made all efforts to maintain and increase the camas. The ripe camas seed heads are all that is visible this time of year.

Since I built my house, subdivisions have grown up around me and storm drain pipes now feed water into the creek rather than water flowing in a sheet across the landscape. The creek channel is not straight and has been allowed to fill with plants to filter the water. When there is a large summer shower, the water from the neighboring subdivisions washes into the creek. When this water hits an impediment, the soap from car-washing foams up. Last summer, after the heavy rain shower in August, there were mounds of soapsuds 5 feet high in the creek.

A pleasing mix of natives and hardy ornamentals eliminates the need for chemicals and excessive watering

Many flowers live in the streambed: False Nettle has pink/purple flowers. Marsh buttercup is the spreading plant with “buttercup” flowers. Nightshade is the spreading plant with purple flowers. Red twig dogwoods were planted.The groves of Oregon White Oak (Quercus Garryana) support many birds including woodpeckers and other insect feeders. Leaves and fallen branches are used as mulch in the garden beds. In the time I have lived here, all the native squirrels have been replaced by the introduced, larger gray squirrel. Much the pity, it is more akin to a rat than wildlife.

View from the deck shows a trail wandering among the towering oaks and planted beds. The stream is at the rear of this view.

Looking at the evergreen trees in the area, you will observe the dead brown ends on the east side branches. This winter we had a week of freezing at night and thawing during the day. The east wind blew persistently. The wind desiccated the freezing/thawing branches and killed them. Looks like it will make the trees more lopsided. I checked with a forester who said the killing was not caused by acid rain. The first signs of that would be dead moss and lichens which are much more sensitive to pH than trees.

The headwaters of our creeks and streams do much to clean the surface water and support amazing communities of plants and animals. The work that the Rock Creek Watershed Partners is doing to educate people on the importance of these areas is essential to preserving and enhancing them.

For more information about the group, see their website at or contact Amanda Wilson, Stewardship coordinator at 503-629-6305, extension 2953.



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Publisher/Editor:Virginia Bruce
12110 NW West Rd
Portland, OR 97229