 The Nature Conservancy says it will keep 240 acres of rare old-growth forest in northeastern Minnesota protected under a purchase from polar explorer Will Stieger. The land near George H Crosby Manitow State Park has towering trees believed to be older than the state of Minnesota. The Conservancy said Wednesday that it's adding the property, which contains old-growth white spruce, white cedar, sugar maple, and yellow birch to its upper Manitow Forest Preserve. Now expanding, that will expand it to 2,450 acres that are open to the public. Minnesota has less than 4 percent of its original old-growth forest defined as natural forest at least 120 years old that haven't been burned or logged. Stieger, who refused offers from loggers and developers, says he's pleased the land will remain protected. If you've enjoyed this segment of Lakeland News, please consider making a tax-deductible contribution to Lakeland Public Television.