Lessons from montane forests of the Pacific Northwest

For almost two decades, we have been studying the water relations and carbo n economy of a wide range of species in the Pacific Northwest of North Amer ica. In particular our studies have focused on the montane species, Abies a mabilis, and have spanned from the foliage to the stand level and from youn g saplings to old-growth trees. We have examined trees as small as 1.1 m to those over 44 m tall and spanning in age from seedlings to 220 years old. All of our study sites are located within 10 km of each other on the west s lope of the Cascade mountain range, at an elevation of 1200 m (+/- 50 m). T his paper focuses on the role that a foundation in production ecology and c anopy dynamics has had in our efforts to understand function and to address issues of integration and scaling. For example, what techniques and approa ches can be used to scale gas exchange measurements (i.e., transpiration, r espiration and photosynthesis) from the shoot level to the tree and stand l evels?