The four dominant tree species I found at Hyland Woods Natural Area were Psuedotsuga Menzeisii (Douglas Fir) , Corylus avellana (common hazel), Acer circinatum (vine maple), and Acer macrophyllum (big leaf maple). In this final report, I will be highlighting traits of each species that allow them to survive in the Hyland Woods ecosystem.
Psuedotsuga Menzeisii is an Oregon native that dominates many forests. What makes this tree so successful in many forests of the Pacific Northwest is primarily its rapid growth rate, allowing it to grow in successional forests and compete for light, being a shade intolerant tree. Psuedotsuga Menzeisii is also a successful reproducer because it produces many large and hardy seedlings1.
Corylus avellana is a non-Oregon native, but it is a heavily prevalent species in Oregon due to its use for cultivation. It originated in Europe, and was brought over to the US to cultivate hazelnuts. Oregon is the largest producer of hazelnuts in the US4. This tree does well in moist, sun to part shade environments, which allows it to survive in a Psuedotsuga Menzeisii dominated forest such as Hyland Woods.
Acer circinatum prefers moist, shady environments, but is tolerant to an array of light conditions. It reproduces large seeds, increasing its reproductive success².
Acer macrophyllum prefers sun to part-shade, and cool moist environments, characteristic of the Pacific Northwest3. Like Acer circinatum, it produces large but also numerous seeds5. Its large leaves and canopy cover allow it to capture light, even in the shaded understory of towering Psuedotsuga Menzeisii.
Hyland Woods Natural Area is diverse forest nestled in a developed area. All of the tree species are well adapted to a cool and moist climate that is characteristic of the Pacific Northwest. What determines the success of vegetation within this forest is primarily driven by its tolerance of conditions created by Psuedotsuga Menzeisii. With Psuedotsuga Menzeisii being the greatest competitor for light, the other species living beneath its canopy must be adapted to shade to part-shade conditions.
References:
1Franklin, J. F., & Halpern, C. B. (2000). Pacific Northwest Forests. In M. G. Barbour & W. D. Billings (Eds.), North American Terrestrial Vegetation. Cambridge University Press.
2Landscape Plants. (n.d.). Retrieved from https://landscapeplants.oregonstate.edu/plants/acer-circinatum
3Landscape Plants. (n.d.). Retrieved from https://landscapeplants.oregonstate.edu/plants/acer-macrophyllum
4Landscape Plants. (n.d.). Retrieved from https://landscapeplants.oregonstate.edu/plants/corylus-avellana
5Tappeiner, J. C., & Zasada, J. C. (1993). Establishment of salmonberry, salal, vine maple, and bigleaf maple seedlings in the coastal forests of Oregon. Canadian Journal of Forest Research, 23(9), 1775–1780. doi: 10.1139/x93-224
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