Sorry, I'll work to remove the foreign tags.
They are county owned tiled ditches (agricultural drain tile), meaning they are trenched roughly a meter below the ground as corrugated pipe. So, I'm not sure what the right tag is if not drain. Pipeline?
All public tile is mapped by county
https://maps.co.jackson.mn.us/apps/citizenservicerequest/default.htm

Although, did you remove landscape features that I took time to draw in? I've been to many WMAs in my area and many can be defined as grasslands, which I don't think is an oversimplification. As a grassland can include wetlands and trees and I usually add in those features. I agree with you for large forests and features generally greater than just a few square miles.

Fair enough.