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Stand Initiation. Competition with different life forms. Herbs Forbs Grasses Woody shrubs. Competition with many species. “ brushy stage”. Wide range of ages. A small advantage in years can be a large advantage in competitive ability. eastern white pine (. Pinus strobus. ).
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Competition with different life forms • Herbs • Forbs • Grasses • Woody shrubs
Competition with many species • “brushy stage”
Wide range of ages • A small advantage in years can be a large advantage in competitive ability
eastern white pine ( Pinusstrobus ) Steven Katovich, USDA Forest Service, Bugwood.org
Wide variation in site • Small plant size magnifies the growth effects caused by subtle variations in microenvironment • Microsite is the entire environment of the individual • Trees are in more vulnerable position • e.g. leader frost damage
Stand environment changing rapidly • Site is still responding to previous disturbance • ‘assart’ effect • Nitrogen fixing herbacious vegetation
Unfilled (available) growing space • Free to grow stage
Harper sieve • ‘Can’t be old if you die young’ • Nature selects for competitive ability during stand initiation stage • Tree breeding programs do not – require management