The season seven alumnus announced his decision in a Twitter message: "The day has come. #GoodbyeDreads," the Hollywood Reporter said Tuesday.
A video clip posted on his Instagram account showed his sister Jackie brandishing the scissors as she lopped off the locks Jason had sported since his senior year at a Texas high school.
Castro, 26, didn't release a reason for the "dread"-ful action, but season nine runner-up Crystal Bowersox did the same thing last month.
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