Agenda - Parks and Recreation Commission - 09/20/2001

Home

-56- Minnesota Forests Tee acreage of Minnesota's forests bas greatly decreased since the first European sextets amved. Teen, about 31.5 million acres of our state's 51.2 million acres were forested. With the development of agriculture, roads, and cities, forests now cover only about 16.7 million afros. Fortunately, tree planting and natural succession are restonng some of ~e previously forested lvlinnesota's forests have immense economic and environmental importance. The production and processing of wood and wood fiber is the second largest manufacmnng industry in Minne- sota. Millions of tourists and recreational users are attracted, to the beauty and solitude of our forests. Fores= also provide habitat for wildlife, protect soils, and renew water resources. And they enhance the appearance of communities and promote health by reducing noise, cutting energy costs, screening unsigAdy views, and attracting songbirds and other wildlife. Your interest in learning more about trees is a major step toward protecting and enhancing these values, Shade Tolerance, Growth Rate, and Life Span 1'"ne tree descriptions in this book include remarlcs about tree uses, habitat, Landscape limita- tions, and unique chm-acterisfics. They also note shade tolerance, height growth rate prior to maturity., and ~pical life span. Shade Tolerance Shade tolerance describes the species' ability to establish and survive in various degrees of shade. Shade-intolerant species require tull sunlight. Intermediate species can survive in partial shade. Shade-toierant species can survive in dense shade. These classes not only provide impor- tant species selection information for planting, they atso can 'help you differentiate species growing in a shaded forest from those growing in full sunlight. Growth Rate Growth rates are hazed on the height increase of a tree growing under average conditions in the Upper Midwest prior to maturity. Slow-growing is defined as 12 inches or tess per year; moder- ate-~owing, [.3 ro 24 inches per year; and fast-growing, 25 inches or more per year. Trees grow condnuousiy, but growth usually slows after maturity. Life Span Trees are described as short-tired (less than 76 yea.rs), intermediate (76 to Lh0 years), or long- tired (longer than [50 years). A tree's.life span is influenced by many factors (e.g.. disease, damage). Downtown urban trees, for. example, on average live only l0 percent as tong as trees in rural areas. Therefore, the classes piovided, should only be.viewed as potential ages. Minnesota Trees