Merrily Enquist

Envisioning the Tillamook State Forest (TSF) requires a vivid imagination. For instance, picture about 365,000 acres - or 568 square miles of nearly 60-year old Douglas-fir. Think of it also as the largest reforestation project ever undertaken. Think of all the backaches resulting from planting 72 million seedlings. Today, one could drive Highway 6 through the TSF and believe the project is complete. However, the TSF still is a huge on-going multifaceted project.

About 45 OSWA members and interested friends from Clackamas and Washington counties toured five sites within the TSF on July 21 with Doug Decker, Director of the Tillamook Forest Interpretive Program. In addition to hearing a great deal of historical information, the group visited sites involving commercial thinning operations, laminated root rot pockets, bio-diversity projects, recreation opportunities, and viewed the implementation of the structure based management plan which has been adopted for the TSF.

The TSF is a young forest - a man-made marvel. Oregonians can take great pride in this forest that has risen from the ashes of four major forest fires occurring between 1933 and 1951. Many people recall the terrible fires, the heat and smoke, and the terrible losses. Much of what is now the TSF was in private ownership when the fires began. Those owners, having lost their timber, soon fell behind in their property taxes. Eventually ownership of the land passed to the state and ownership of the trees went to the affected counties. Faced with a complex of government ownerships and lacking the means or organization to reforest, the project was effectively transferred to the people of Oregon and the Tillamook State Forest was established. The rebuilding of the forest had begun.

In the years since the devastating fires, many people have been involved in the restoration of this forest. Foresters, loggers, professional tree planters, inmates and volunteers as well as all those who voted in 1948 to pass a constitutional amendment authorizing the sale of $12 million in bonds to rehabilitate the land.

Rebuilding produced an evenage forest of primarily Douglas-fir. While this is a valuable asset, the new forest fell short of meeting modern demands including bio-diversity and viable wildlife habitat. Make no mistake, the present forest is a remarkable transformation, but not the natural forest of before. Historic photographs show a variety of age classes, mature and medium aged stands as well as open areas caused by lightening fires or severe wind storms. The forest had a mosaic appearance.

To regain the diversified forest that existed before the fires began could happen naturally but it would require centuries. Today, with best available wisdom and countless hours of input from every conceivable source, the TSF is now being managed with a view to mimicking nature, maintaining habitats for species in danger of extinction, protection of streams, stream sides, and wetlands - while maintaining a sustainable timber source, fighting root rot and Swiss needle cast, producing income to operate the forest and meet its financial obligations to the affected counties and the State of Oregon, and providing separate recreation opportunities for fishermen, hikers, campers, equestrians, and a variety of off-highway vehicle enthusiasts. The system is called structure-based management. Chadwick Oliver, professor of Forest Resources, at the University of Washington is credited with developing many of the underlying concepts of structure-based management. The plan calls for carefully planned management that will attain within a few decades the bio-diversity of pre-catastrophe days.

A landscape approach called structure-based management follows nature's stand development patterns, and does it in fewer years. Using thinning and other techniques such as creating snags and leaving down wood and older trees helps evolve more quickly the qualities of older stages. In an abbreviated form, the five major stages of the management are as follows:

1. Regeneration. This begins after a disturbance such as harvest, fire, or wind has killed or removed most or all of the larger trees. The site is occupied by various conifer or hardwood seedlings as well as shrubs and grasses.

2. Closed Single Canopy. Trees fully occupy the site and form a single, main canopy layer. There is little or no under story of vegetation. As less competitive trees die, snags and down wood appear.

3. Under story. Gaps in the tree canopy provide adequate light to allow a shade tolerant diversified understory of shrubs and herbs to develop.

4. Layered. This stage involves a canopy of two or more layers in addition to a diverse layering of growth in the understory.

5. Older Forest Structure. This stage requires trees with desirable wildlife characteristics and a minimu#m of eight trees per acre, 32-inch diameters. In addition there should be two or more layers of understory, six snags per acre, and considerable down wood in various stages of decay. Presently sixty-three percent of the TSF presently falls within the closed single canopy stage.

When will the TSF achieve having prescribed percentages of each type structure? That is an unanswerable question. As different species are planted, a complex of growth rates must be taken into consideration. Diseases are a factor. How much will Swiss needle cast slow the growth? Will root rot continue to be a serious factor or will present control measures help to control its spread? Presently affected and at-risk trees are removed and western redcedar is planted. Regular reviews are planned to check on progress of the entire program.

The final stop of the day took the group to a future site of the planned Tillamook Forest Interpretive Center. Located near the historic Smith Homestead and Lee's Camp along Highway 6, the 16,000 square foot center will be situated alongside a picturesque narrow gorge of the Wilson River. This particular area just happens to be the storied site planted entirely by school children. Doug Decker emphasized that to understand the TSF one must know its history. The interpretive center will cover the history from the earliest Native American days to the present. If possible, the Center is scheduled to be opened in 2003 - but definitely in time for the Lewis and Clark Celebration in 2005.

To learn more about TSF, click on the ODF web address, www.odf.state.or.us.

Editor's Note: Merrily Enquist is a Master Woodland Manager and a tree farm owner. She wishes to acknowledge her various sources for this article: Doug Decker; Tillamook Forest Times; and the brochures Pathway to the Future for Northwest Oregon State Forests and Just What is Structure-Based Management published by the ODF. Readers may wish also to review Scott Hanson's article in the May 2001 issue of the Forest-Tree Leader on the TSF. Jack Carter and Dick Caldwell, program chairs, are to be congratulated on arranging an outstanding educational tour.