Ponderosa returns to the Willamette Valley

Last Updated: 
February 2, 2010

CORVALLIS, Ore.— Ponderosa pine is characteristic of the east slopes of the Cascade Mountains. Yet, few people realize that a special race of Ponderosa pine once flourished in the Willamette Valley.

Well-known botanist David Douglas described large native ponderosas he saw growing in the prairies and oak savannas throughout the valley as he passed across in the 1820s.

Efforts by Oregon State University scientists, Extension Service and others are bringing back the native tree to the Willamette Valley, where it has not been prevalent for generations.

This unusual race of ponderosa pine is especially adapted to the heavy clay soils and fickle microclimates of the valley, according to Rick Fletcher, OSU Extension forester in Benton County. It grows in wet areas, on dry knobs and among grazing livestock. The tree's deep taproot keeps it firm in wind storms.

This well-adapted pine thrived in the valley for thousands of years. But since 1850, urban and agricultural development reduced its population significantly. During the 1980s a group of local foresters, landowners and conservationists began efforts to restore this race to its native range. Their efforts grew into the Willamette Valley Ponderosa Pine Conservation Association.

Through the conservation association, OSU scientists helped to identify and map remnant pine stands, establish a gene conservation planting to preserve existing genetic sources and promote planting and growing of this race in the Willamette Valley.

Seed is available from the gene conservation planting, and local forest nurseries sell stock for homeowners and others to plant.

"The Willamette Valley Ponderosa pine is as beautiful as its eastside cousin and grows much faster, Fletcher said. "The pine is appropriate for many valley stream banks and on soils that would be marginal for other tree species."

Pine plantations coexist well with grazing livestock or other rural land uses, and can provide a future source of timber. Ponderosa pine's deep root system and stately form also make it an attractive choice for city parks, urban areas and watershed plantings.

More information on the Willamette Valley Ponderosa Pine Conservation Association is online at their Web site.

If you are interested in planting Ponderosa pines in western Oregon, be sure to purchase seedlings that are native to the Willamette Valley. Contact your local OSU Extension office or Oregon Department of Forestry to find the nearest source of seedlings.

Author: Judy Scott
Source: Rick Fletcher