1. Stand Initiation

5. Competition with different life forms
Herbs
Forbs
Grasses
Woody shrubs

7. Competition with many species
“brushy stage”

9. Wide range of ages
A small advantage in years can be a large advantage in competitive ability

10. eastern white pine ( Pinus strobus )
Steven Katovich, USDA Forest Service, Bugwood.org

11. 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

14. Stand environment changing rapidly
Site is still responding to previous disturbance
‘assart’ effect
Nitrogen fixing herbacious vegetation

16. Unfilled (available) growing space
Free to grow stage

18. 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