RENO — Prosecutors won’t press charges against the 58-year-old Washoe Valley man whose improper disposal of ashes from his fireplace sparked the wind-whipped brush fire that destroyed 28 homes south of Reno last January, caused $4.5 million in damage and was blamed for the death of an elderly woman.Chief Deputy District Attorney Kristin Erickson said in a memo released Tuesday that she doesn’t believe Lyle Teuscher was guilty of any crime.“Although the fire was horrific, it was not a criminal act, but was accidental in nature,” Erickson said in the memo endorsed by District Attorney Richard Gammick.Teuscher told investigators he …