IIRC, Mineral vein (mining) and Grove (logging/harvesting) are both a set number of harvests for rank ups as well. The difference is that those are counted for each harvest attempt with large daily caps, while furrows are counted once per row harvested. It's just a bit of spamming Enter for maybe a minute to clear out your vein for your 10x daily harvests, but you only get your 1x per row from furrows.
The main complaint I have here is actually only that none of the details are laid out in-game. ><;; There is no where that even hints at how furrows will lag if you don't harvest 2-3x per row daily. There is also no where that explains that if you go w/ the fastest growing things and pull all-nighters, you can be done w/ furrows in ~7x days. XD Even though that is far from a good idea, goes against the spirit of the Login Warning telling you not to forget your friends and family out here in reality, and would require 43x stacks of Revival Roots, the very fact that it is mathematically and systematically POSSIBLE is most likely why the devs refuse to change it.