Floodplain forest vegetation cover maps to support effectiveness monitoring of channel and floodplain restoration projects along the Willamette River, Oregon

This dataset consists of repeat vegetation cover maps of multiple Willamette River restoration sites where restoration activities were implemented to increase the area of floodplain forests. Beginning in the early 21st century, large-scale restoration programs have been implemented along the Willamette River, Oregon, to address historical losses of floodplain habitats for native fish (Keith and others, 2022). For much of the Willamette River floodplain, direct enhancement of floodplain habitats through restoration activities is needed because the underlying hydrologic, geomorphic, and vegetation processes that historically created and sustained complex floodplain habitats have been fundamentally altered by dam construction, bank protection, large wood removal, land conversion, and other influences (for example, Hulse and others, 2002; Wallick and others, 2013). Floodplain forest vegetation cover was derived from R Random Forest classification of 2009, 2011, 2018, and 2020 aerial imagery at three large-scale floodplain planting restoration sites along the Willamette River: Harkens Lake (river kilometer [RKM] 153-154.5), Snag Boat Bend (RKM 144-147), and Luckiamute State Natural Area (RKM 108-111). The overall goals and approaches for the repeat mapping are based on a previously published effectiveness monitoring framework for Willamette River restoration activities (Keith and others, 2022). The repeat mapping datasets include GIS layers defining two classes of vegetation cover (forest and not-forest, condensed from six cover classes: forest, not-forest (agriculture), not-forest (other), water, shadow in forest, and shadow in non-forested areas). This mapping can be used to support an assessment of changes to floodplain forest vegetation cover at sites along the Willamette River floodplain where restoration activities were implemented from 2012 to 2020 to increase the area of native floodplain forest vegetation.