Earlier quoted context omitted.
> The farmland’s 40$/year in taxes isn’t pushing anyone to sell I don't think that's an easy assumption to make. Cost of living, average income, and average plot size are very different in rural areas. I don't know Idaho so I can't speak to land value there, but I can say farmable land in rural Alabama goes for between $1k and $6k per acre depending on the land. If you really want to farm it for anything more than a…
For land assessment, many countries or municipalities assess it regularly. In my country (New Zealand), most city councils re-assess land value and improvements value every three years (and charge council rates based on them).
I live on around 80 acres (30 hectares?). Our land is a bit unique in the area, and in general there hasn't been a single piece of land sold near us since before the pandemic and all the economic change that came with it. I don't know how the county could possibly know what our land is worth until something similar sells on the open market again.