Were the fields used for grazing temporarily during the 2022 drought? AcreValue shows that the land was used for "Grass/Pasture" and "Non-Cropland" during that year. There also appears to be animals grazing the fields in Esri Clarity, but that could be from well over a decade ago.

About the other landcover, a lot of it appears to be traced from Esri imagery, so that would explain the patterns west of US 95 not matching up with the Bing imagery, but I can't really see anything outside of large shrubs or standalone trees that would count as natural wood - not from the aerial imageries provided by OSM nor the Bing/Mapillary streetview from Interstate 80. It's completely different from the natural wood you've been mapping in the mountains (which does look great, by the way), which is actual forest versus wetland with some scattered trees, so the distinctions you're trying to make between natural area tagging around this area aren't entirely clear to me.