Mr. Sterling became a serious horticulturist in the early 1950's.
Mr. Sterling said he was a victim of racial discrimination throughout his career at the agency.
Mr. Sterling said other black case officers shared his feelings but were afraid to speak up.
Mr. Sterling also said he believed that his experience showed how difficult it had been for the agency to adapt to a changing world.
In fact, Mr. Sterling was just the sort of person whom the agency has said it wants to recruit.
Mr. Sterling was arrested the next day at his drug treatment center.
Mr. Sterling, who was described by the police as a convicted drug dealer, remained free yesterday evening.
"It became clear that he could not finish the book and run for president," Mr. Sterling said.
Mr. Sterling said he does not expect to withdraw the money for five more years - when he will be 62.
Mr. Sterling has noted the emergence of this trend over the past three or four years.