Also, why are you marking everything as grassland? grassland is wild grass, see like a prairie in America or puszta in Hungary. See https://wiki.openstreetmap.org/wiki/Tag:natural%3Dgrassland and https://wiki.openstreetmap.org/wiki/Pl:Tag:natural%3Dgrassland . Also note that what the wiki says is used in Poland does not mean it applies in other countries.