Richard Horan set himself on an unusual mission: to travel the United States to collect seeds from trees in the yards of famous people in our nation’s history. His quest took him to find trees that gave Elvis shade at Graceland to Abraham Lincoln’s boyhood home in Kentucky. Author Richard Horan talks with Living on Earth’s Steve Curwood about his new book, “”Seeds, One Man’s Serendipitous Journey to Find the Trees that Inspired Famous American Writers.”