Brochure 9 in IRR Series

December 22, 2003

Goal 11, Policy 3.B.(1). This Josephine County Comprehensive Plan (JCCP)1 policy permits requests involving changes for lands from a resource designation (i.e., woodlot resource) to a non-resource designation through the internal rate of return, or IRR procedure.2 The Hugo Neighborhood Association has concerns with the present application of the IRR system in the amendment process.3

Josephine County has 1,040,000 acres of land in 111 soils as defined by the Soil Survey.4 Sixty-seven (67) soils were identified as commercial forest soils (789,816 acres, 76% of Josephine County) and 46 were defined as agricultural lands by the Soil Survey.

IRR Zoning

The Brown Report made a zoning recommen-dation based upon its IRR ratings which was acknowledged as part of the JCCP. Soils below 3.50 IRR are considered unsuitable as forest lands (non-resource lands - JCCP, Goal 11, Policy 3.B.(1)); those with an IRR rating between 3.50 and 3.99 IRR are considered suitable for the Woodlot Resouce zone; and those soils having an IRR greater than 4.00 are considered suitable as commercial forest land.

Results Of IRR Zoning To Forestry Base

The IRR approach does not rate or eliminates 40 soils suitable for the production of commercial trees (Table 6, Soil Survey); they are considered non-resource lands by the county. The IRR approach also eliminates from consideration 26 agricultural soils (Table 5, Soil Survey) as having any forestry productivity potential (calculations not considered in this brochure).

The IRR approach identifies 12 soils as suitable for commercial forestry.

It identifies 15 soils suitable for the Woodlot Resource zone for a total of 27 soils with an IRR of 3.5 or greater and suitable for production of commercial trees. The 27 soils cover 373,402 (36 %) acres.

Conceptually, the IRR approach eliminates half of the economic forestry land base in the county - minus 416,414 acres of commercial forest land.

More Information. Would you like to learn more about citizen involvement in land use planning? Contact a member of the Land Use Committee of the Hugo Neighborhood.

1. Josephine County. October 2000. The Comprehensive Plan For Josephine County. Grants Pass, OR.

2. Lawrence F. Brown. 1985. Using The Internal Rate Of Return To Rate Forest Soils For Applications In Land Use Planning. Grants Pass, OR.; Michael Snider. 1999. Locational Factors Affecting Woodlot Resource Lands. Josephine County Planning Office. Grants Pass, OR.

3. Hugo Neighborhood Association & Historical Society. 2003. The IRR Series: What Are Resource Lands?, Woodlot Resource To Non-Resource Lands; Evaluation: Internal Rate of Return - IRR; Top IRR Rated Agricultural Lands; Non-rated Soils & IRR System; Quasi-Judicial Amendments, Compliance With Goal 3 - Agricultural Lands, Compliance With Goal 4 - Forest Lands, Brown Report: IRR Zoning, Composite IRR, and IRR. Grants Pass, OR.