Do provinces with "Arid Ground" count as desert? More specifically, do I need to worry about the armor level when fighting in Arid Ground because my troops will tire too fast?

Also, I read that when fighting in the desert, use troops without armor - or armor 5 or less. Just want to verify that Men at Arms are OK to use? They are armored, but the armor value is only 3 (according to the unit guide I have)