Some people like to hug trees, and others prefer to carefully plot them on maps. New Yorkers Ken Chaya and Edward Sibley Barnard spent the past two-and-a-half years mapping the precise location and species of 19,933 trees in Central Park -- about 85% of the park's total vegetation. "You can't have every tree. There's great hubris in wanting every tree. But we got the big ones, we have the important ones," Chaya said.