Highway 62 Scenic Corridor Vegetation Management

The ten mile stretch of Highway 62 from Prospect Ranger Station to Union Creek, known as the "Scenic Corridor" is an area of special historical significance on the Rogue River-Siskiyou National Forest. With masses of young trees and thick undergrowth springing up around tall old trees, the area may initially look luxuriantly healthy to the untrained eye. However, an extensive survey conducted in 1994 and 1995 by the Southwest Oregon Forest Insect and Disease Technical Center determined a high rate of mortality in what was once deemed by recreationists more than a hundred years ago as, "the greatest stand of sugar pine in the world."

Historically sugar pine, ponderosa pine, and western white pine were the dominant species of trees in the Corridor, along with some scattered Douglas-fir. White fir, now well established, did not arrive until later. The old military road to Crater Lake wound its way through the giants past the famous "Mammoth Sugar Pine," a seven foot, eleven inch diameter tree that stood 224 feet tall. When the military route was relocated and paved in the 1920s and 1930s to become the present day Highway 62, an interpretive site was developed to direct travelers to the old Mammoth Sugar Pine. In the decades that followed, trees in the corridor suffered from bark beetle infestations, blister rust, and root rot among the Douglas-fir and later white fir.

Ellen Goheen, Rogue River-Siskiyou National Forest's plant pathologist for the Southwest Oregon Forest Insect and Disease Technical Center, notes that bark beetles are attracted to stressed trees by somehow being able to sense their chemical state. The beetles then put out their own pheromones to attract more beetles until the tree is fully infested. Then they put out a different signal when the tree is full so other beetles will know to search elsewhere. Blister rust is also causing weakening and mortality. It is an imported disease which came to this area in the 1920s. It thrives in moist, damp weather and attacks five needle pines such as sugar and western white pine of all ages.

Meanwhile, the pine trees, which require much more light and space in order to thrive, have little success in growing back where older trees die and are being replaced by thick patches of Douglas and white fir. Unfortunately many of the older Douglas and white firs suffered from root rot (which does not attack the pines), leaving numerous pockets in the corridor entirely devoid of overstory trees. (Summary of insect and disease survey.)

In an effort to discover the public's understanding of the issues, the Rogue River-Siskiyou National Forest worked with Southern Oregon University's Southern Oregon Regional Services Institute to develop and analyze a public response form using five images representing current and historical conditions of the Corridor as well as possible treatments. Other partners involved included SOU's Southern Oregon Center for Social Research, who helped develop the response form and methodology, and SOU's REAL Corps, who interviewed visitors and residents of the Corridor area. Analysis of the responses showed that people modified their opinions of what they felt was visually preferable given information related to forest health concerns depicted in the images found in the right-hand column.

To further develop understanding of the issues related to forest health in the Corridor, a site at the intersection of Forest Roads 60 and 68, and Highway 62 was selected to initiate a demonstration project that will allow the public to compare various recommended treatments that are intended to conserve and enhance the historic pine forest of the area. In the summer of 1998 a treatment of low intensity thinning of material less than 8 inches in diameter and pruning limbs of remaining trees was performed on the southwest corner of the intersection. It's anticipated that the other corners of the site will display treatments that include thinning and low intensity burning, thinning all competing trees to at least 20 feet beyond the drip lines of selected pines to be retained, and control area with no treatment.

Other treatments recommended by Ellen Goheen in various portions of the Corridor will include planting specially developed rust resistant white pine and sugar pine in more open areas where white and Douglas-fir have been killed by root rot.

The Highway 62 Vegetation Management Project is an excellent example of Sustainable Ecosystem Management, one of the four cornerstones of the Forest Service Natural Resource Agenda, as well as a great effort to preserve a valuable part of our local forest history.