We mowed last week. It didn't really need it, but there were wild onions and such that were sprouting up higher than the grass which drives DH nuts.
We live on 28 acres and we have one acre for 'yard' then another 5 acres that we keep mowed for the kids to use (trampoline, basketball, bonfires, etc). The rest is wooded thank goodness or we'd be haying it like eskimo mentioned.