Crew-cut or mop-top? In the early 1960s, the Beatles stirred up a generational divide and instigated plenty of push-back from parents when their sons let their hair grow. Then the guardians of convention moved on, and men’s hairstyles have never been the same. Will it be the same for low-mow lawns, the mop-tops of the landscape world? I've met plenty of people who are planning to switch.