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• 1. [Article] A preliminary investigation into the use of the tarif system and three tree selection methods for obtaining Douglas-fir stand and stock tables from large-scale aerial photography

  As a preliminary step toward the establishment of a 70 mm. aerial photo timber inventory system capable of generating accurate stand tables, stock tables, and gross volume estimates, this project focuses ...

  Citation × Citation Citation Abstract Copy Title: A preliminary investigation into the use of the tarif system and three tree selection methods for obtaining Douglas-fir stand and stock tables from large-scale aerial photography Author: McCadden, Richard Jay As a preliminary step toward the establishment of a 70 mm. aerial photo timber inventory system capable of generating accurate stand tables, stock tables, and gross volume estimates, this project focuses on the development of a system which (1) eliminates the need to measure tree height on the photos through use of the tarif system and, (2) incorporates the use of three distinct tree selection methods-- fixed plot, variable plot, and line transect sampling. The methodology is developed and applied to a 346 acre parcel of Douglas-fir forestland. The accuracy of individual tree predictions for diameter at breast height, volume, tarif number, and tree height (which is derived without traditional photo measurement) are evaluated by ground subsampling a 206- tree validation set and comparing actual and predicted values. The results show that an average underprediction of ground-measured tarif number by about 5% occurs, which in turn results in similar underpredictions of tree volume and height. The accuracy of the stand tables, stock tables, and gross volume estimates are examined by comparison to independently derived ground measurements. The photo estimates of mean gross volume per acre, using each of the three photo tree selection methods, are all within 5% of the ground-derived estimates; in all cases the 68% confidence intervals of the ground and photo estimates overlap. Graphic comparisons of the photo and ground-derived stand and stock tables are presented; they are similar, except for the inability of the photo method to accurately predict the stocking of trees less than twelve inches in stem diameter. The aerial photo system, using each of the three tree selection methods, demonstrates an ability to produce results comparable to those derived from conventional ground inventory techniques. Future research is recommended, and specific needs for this research are identified. Title: A preliminary investigation into the use of the tarif system and three tree selection methods for obtaining Douglas-fir stand and stock tables from large-scale aerial photography Author: McCadden, Richard Jay As a preliminary step toward the establishment of a 70 mm. aerial photo timber inventory system capable of generating accurate stand tables, stock tables, and gross volume estimates, this project focuses on the development of a system which (1) eliminates the need to measure tree height on the photos through use of the tarif system and, (2) incorporates the use of three distinct tree selection methods-- fixed plot, variable plot, and line transect sampling. The methodology is developed and applied to a 346 acre parcel of Douglas-fir forestland. The accuracy of individual tree predictions for diameter at breast height, volume, tarif number, and tree height (which is derived without traditional photo measurement) are evaluated by ground subsampling a 206- tree validation set and comparing actual and predicted values. The results show that an average underprediction of ground-measured tarif number by about 5% occurs, which in turn results in similar underpredictions of tree volume and height. The accuracy of the stand tables, stock tables, and gross volume estimates are examined by comparison to independently derived ground measurements. The photo estimates of mean gross volume per acre, using each of the three photo tree selection methods, are all within 5% of the ground-derived estimates; in all cases the 68% confidence intervals of the ground and photo estimates overlap. Graphic comparisons of the photo and ground-derived stand and stock tables are presented; they are similar, except for the inability of the photo method to accurately predict the stocking of trees less than twelve inches in stem diameter. The aerial photo system, using each of the three tree selection methods, demonstrates an ability to produce results comparable to those derived from conventional ground inventory techniques. Future research is recommended, and specific needs for this research are identified. Close

• 2. [Article] Evaluating downstream channel changes in response to a small dam removal on the Calapooia River, Oregon with respect to measurement errors and prior aerial photo observed changes

  The objective of this study was to evaluate the use of aerial photos as a substitute for multiple-year pre-removal field data to assess the downstream channel changes associated with a small dam removal. ...

  Citation × Citation Citation Abstract Copy Title: Evaluating downstream channel changes in response to a small dam removal on the Calapooia River, Oregon with respect to measurement errors and prior aerial photo observed changes Author: Walter, Cara The objective of this study was to evaluate the use of aerial photos as a substitute for multiple-year pre-removal field data to assess the downstream channel changes associated with a small dam removal. The Brownsville Dam, a 2.1 m tall concrete dam on the Calapooia River, Oregon, was removed in 2007. We surveyed cross sections below the dam during the summers prior to (2007) and follow (2008) removal, and we analyzed aerial photos from 1994 to 2006. The field surveys and aerial photos were used to map the low flow channel and bars over 1.3 km downstream from the dam and in an upstream control reach. Three types of measurement error (position error, identification error, and wetted boundary datum error) were assessed for the field surveys and aerial photos in order make the two methods of measurement more comparable. The first year after the dam removal, we observed changes in bar width, wetted width, and wetted width midpoint as large as 17 m ± 3 m immediately below the dam. We inferred that channel changes below the dam after removal were a result of the removal through comparison with pre-dam removal aerial photos, where changes up to 67 m ± 24 m were predominantly far from the dam, and an upstream control, where changes were only as large as 9 m ± 5 m. We conclude with suggestions of best practices for reducing errors, including establishment of permanent monuments for field surveys, taking measurements at similar, well-known discharges, and generating the highest-quality digital aerial photos through source and scanning choices. Title: Evaluating downstream channel changes in response to a small dam removal on the Calapooia River, Oregon with respect to measurement errors and prior aerial photo observed changes Author: Walter, Cara The objective of this study was to evaluate the use of aerial photos as a substitute for multiple-year pre-removal field data to assess the downstream channel changes associated with a small dam removal. The Brownsville Dam, a 2.1 m tall concrete dam on the Calapooia River, Oregon, was removed in 2007. We surveyed cross sections below the dam during the summers prior to (2007) and follow (2008) removal, and we analyzed aerial photos from 1994 to 2006. The field surveys and aerial photos were used to map the low flow channel and bars over 1.3 km downstream from the dam and in an upstream control reach. Three types of measurement error (position error, identification error, and wetted boundary datum error) were assessed for the field surveys and aerial photos in order make the two methods of measurement more comparable. The first year after the dam removal, we observed changes in bar width, wetted width, and wetted width midpoint as large as 17 m ± 3 m immediately below the dam. We inferred that channel changes below the dam after removal were a result of the removal through comparison with pre-dam removal aerial photos, where changes up to 67 m ± 24 m were predominantly far from the dam, and an upstream control, where changes were only as large as 9 m ± 5 m. We conclude with suggestions of best practices for reducing errors, including establishment of permanent monuments for field surveys, taking measurements at similar, well-known discharges, and generating the highest-quality digital aerial photos through source and scanning choices. Close

• 3. [Article] Scenic photo of Calapooya Creek

  Calapooya Creek photo

  Citation × Citation Citation Abstract Copy Title: Scenic photo of Calapooya Creek Author: Partnership for the Umpqua Rivers Calapooya Creek photo Title: Scenic photo of Calapooya Creek Author: Partnership for the Umpqua Rivers Calapooya Creek photo Close

• 4. [Article] Scenic photo of the Lower North Umpqua River

  Lower North Umpqua River photo

  Citation × Citation Citation Abstract Copy Title: Scenic photo of the Lower North Umpqua River Author: Partnership for the Umpqua Rivers Lower North Umpqua River photo Title: Scenic photo of the Lower North Umpqua River Author: Partnership for the Umpqua Rivers Lower North Umpqua River photo Close

• 5. [Article] Restoration project photo from the Lower North Umpqua Watershed

  Photo was taken in the Lower North Umpqua Watershed

  Citation × Citation Citation Abstract Copy Title: Restoration project photo from the Lower North Umpqua Watershed Author: Partnership for the Umpqua Rivers Photo was taken in the Lower North Umpqua Watershed Title: Restoration project photo from the Lower North Umpqua Watershed Author: Partnership for the Umpqua Rivers Photo was taken in the Lower North Umpqua Watershed Close

• 6. [Article] Landscape photo from the Deer Creek area of the Lower South Umpqua watershed

  Photo was taken in the Deer Creek area of the Lower South Umpqua Watershed

  Citation × Citation Citation Abstract Copy Title: Landscape photo from the Deer Creek area of the Lower South Umpqua watershed Author: Partnership for the Umpqua Rivers Photo was taken in the Deer Creek area of the Lower South Umpqua Watershed Title: Landscape photo from the Deer Creek area of the Lower South Umpqua watershed Author: Partnership for the Umpqua Rivers Photo was taken in the Deer Creek area of the Lower South Umpqua Watershed Close

• 7. [Article] Scenic photo of the South Umpqua River above Days Creek

  South Umpqua River photo

  Citation × Citation Citation Abstract Copy Title: Scenic photo of the South Umpqua River above Days Creek Author: Partnership for the Umpqua Rivers South Umpqua River photo Title: Scenic photo of the South Umpqua River above Days Creek Author: Partnership for the Umpqua Rivers South Umpqua River photo Close

• 8. [Article] Scenic photo of the West Fork of Cow Creek

  West Fork of Cow Creek photo

  Citation × Citation Citation Abstract Copy Title: Scenic photo of the West Fork of Cow Creek Author: Partnership for the Umpqua Rivers West Fork of Cow Creek photo Title: Scenic photo of the West Fork of Cow Creek Author: Partnership for the Umpqua Rivers West Fork of Cow Creek photo Close

• 9. [Article] Scenic photo of Myrtle Creek in the South Umpqua Watershed

  Myrtle Creek photo

  Citation × Citation Citation Abstract Copy Title: Scenic photo of Myrtle Creek in the South Umpqua Watershed Author: Partnership for the Umpqua Rivers Myrtle Creek photo Title: Scenic photo of Myrtle Creek in the South Umpqua Watershed Author: Partnership for the Umpqua Rivers Myrtle Creek photo Close

• 10. [Article] Scenic photo from Olalla Creek-Lookingglass Creek Watershed

  Photo was taken on the Olalla Creek-Lookingglass Creek Watershed

  Citation × Citation Citation Abstract Copy Title: Scenic photo from Olalla Creek-Lookingglass Creek Watershed Author: Partnership for the Umpqua Rivers Photo was taken on the Olalla Creek-Lookingglass Creek Watershed Title: Scenic photo from Olalla Creek-Lookingglass Creek Watershed Author: Partnership for the Umpqua Rivers Photo was taken on the Olalla Creek-Lookingglass Creek Watershed Close