Meadows are resources points around the world. You can tap on them and then on harvest to collect the resources they have. You choose hero and brigades, and depending on you heroes level you can bring more or less troops to collect more or less resources. You can come back home before the harvesting is done.
Meadow levels and number of resources when no one harvested them yet[]
Lvl 5: 4,125,000
Lvl 5: 1,575,000
Lvl 3 - 900,000
Lvl 2 - 412,500
Lvl 1 - 225,000
The bloodsoil has a higher concentration of higher levels resource points, and the bloodsoil near the capital is the only place with resource points lvl 5.