OakQuest 2018 release

This release, OakQuest 2018 (version III), of the Intertwine Alliance's OakQuest data incorporates both of the previous versions I (2016) and II (2017) data releases, minor edits to these previous versions, as well as new data.

With this 2018 release, we consider the whole of the Oregon portion of the RCS planning area complete. The oak map shows concentrations of oak and places where oak is absent. We have “full coverage” of 1,790 sq. miles within Oregon. T he term “full coverage” is used as we have learned that it is as important both to know where the oaks are and where they are not, in order to plan larger-scale work such as connectivity corridors for plants and wildlife. This is area we are confident that where we said there is oak there is oak and where we have no oak we feel confident we haven ’ t ’ missed any significant clusters of oaks. The additional 855 sq. miles within the RCS planning boundary has been spot checked and we feel confident this habitat is not conducive for oaks to grow. Small portions within the state of Washington have been collected but are not included in this release. We hope this information will be funded soon and that we can provide a future release of OakQuest data.

Version I of the OakQuest data was developed from field observations and inspection of high-resolution aerial photography in GIS, as well as other records checked and compiled from existing regional tree inventories in 2014 which included available street, heritage, and other regional tree inventories. During July-Oct 2014 and August-November 2015, community volunteers and natural resource professionals collected field observations of oak and other tree species using a custom smart phone app. Data collected in the field were later spatially adjusted and error-checked within ArcGIS.

During inspection of oak field observations with aerial photos in ArcGIS, Lori Hennings developed an eye for spotting Oregon white oak and additional oak trees visible in high-resolution aerial photography were digitized. Data were converted to a common projected coordinate system and observations were coded by source and category of origin. The version II data release included additional “full coverage” areas, including urban and rural areas, approximately 824 sq miles. However, large portions of the nearly 3,000 sq mile bi-state regional conservation strategy extent had not yet been mapped for oak.

This version III of the oak map data release includes “full coverage” for an additional 766 square miles of the Oregon portion of the Intertwine Alliance RCS planning area. Remaining to be done is the Washington portion of the RCS plan area, which will be included in a future data release.

For portions of the region where high-resolution Metro aerial photography was available, we used heads-up digitizing of points representing Oregon white oak tree canopy centers in ArcGIS. In outlying rural areas where Metro aerial photos were not available, we used heads-up digitizing of oak tree canopy centers over Google and Bing aerial photography in Quantum GIS. For portions of the mapping area we used Quantum GIS because it was free and open source, and enabled the streaming of high-resolution aerial photos without expensive software supplements.