You can harvest by the bud, but it might not realistically be worth it.

Generally the entire plant is in sync when it come to THC and what happens up top happens down low.

Remember, THC is a resin thought to be produced, not to get us high, but to protect and prolong the life of the flower.

Of course if you have no life, like me, sure you can spend the days picking by the bud. But you'll pick them all within a two day time frame or so.

HAPPY TRICH HUNTING