Roughly 2,500 trees and shrubbery find sanctuary at Starhill Forest Arboretum near Petersburg, Illinois, where co-founders Guy and Edie Sternberg practice what they promote in tree conservation. Having founded the arboretum in 1976, the Sternbergs kept at least one existing tree near their residence on the 50-acre property. It’s an Osage Orange from about 1930, and was the largest Osage Orange found in Menard County, Illinois, in a survey conducted in 1985. “Take advantage of a special (existing) tree if you have it,” Guy Sternberg said. “If it’s rare, extra nice, extra pretty or extra-large, in really good shape, try to make that the focus of your landscape. If you have a 50-year-old tree or a 200-year-old tree, you’re not going to regain that in your lifetime.” A certified professional arborist and retired registered landscape architect, Guy Sternberg typically gives from 10 to 12 tree lectures a year. Plus, he’s working …