https://www.facebook.com/sehun.exo29/media_set?set=a.922183791137762.1073741881.100000384495568&type=3&uploaded=14

More pics. It's the very tiny white stuff that looks like frost. The only way I noticed it is because my tree started looking a little whiter. https://scontent-dfw1-1.xx.fbcdn.net/hphotos-xpa1/v/t1.0-9/10392520_10103072971088397_9163302602335128437_n.jpg?oh=d16e87585323d722e83e1066814e1170&oe=55EB7D12 https://scontent-dfw1-1.xx.fbcdn.net/hphotos-xpf1/v/t1.0-9/10277729_10103072970404767_617744826501465214_n.jpg?oh=06bc7c19e54523282bf650c5b6bc28c6&oe=55E8FDE0 https://scontent-dfw1-1.xx.fbcdn.net/hphotos-xtp1/v/t1.0-9/10931485_10103068968075467_8285179676206866480_n.jpg?oh=328c998f4acd9972a1ae70af3a68d453&oe=56296CE3 https://scontent-dfw1-1.xx.fbcdn.net/hphotos-xft1/v/t1.0-9/11427219_10103072982690147_121454886004481529_n.jpg?oh=85ac1288f080a2ae3f7893ee5c68b777&oe=56351BC5

It's a Monarda, maybe M fistulosa, but I don't know them at all well. The Name That Plant Forum will certainly be able to give you a species and or cultivar name. It's hard to see but is the foliage actually variegated or is that just the light?

@GC... let's just say I've been needing to rescue many brown specimens in recent mths :/ not really by choice either @Amy... main stem possibly isn't dead, there could be enough green chlorophyll in new bud to sustain it as a water/nutrient pipe. But it will never regrow its top as that's where these things grow from... your only hope is if it'll sprout another pup on top but unlikely given this time. Also if you disturb it from its soil just for looksee... I don't think that's got enough energy (as a whole) to regrow damaged roots from the bottom. You'd want to just chop & reroot the pup. Hence safest way is to see if pup will bypass root when you bring soil level up to it, whilst still being attached to brown trunk... that's my gutfeel anyway. You've got enough empty depth in pot; if not otherwise I'd pop whole thing as-is into a bigger pot & fillup with coarse sand for a few months. (Or more if it's winter there) & don't water...