Haircuts for a Kohen

Question
Must a Kohen nowadays make sure to take a haircut at least once every 30 days?

Answer
Such a requirement does not exist so long as the Beit HaMikdash is not standing. See Rambam, Hilchot Biat HaMikdash,
Chapter 1, Halacha 11
http://www.mechon-mamre.org/i/8301.ht