1. Spatial Variability of Aspen Bark Chlorophyll Content In the Winter Justin Burman, EBIO 4100, Spring 2011 Winter Ecology Mountain Research Station University of Colorado, Boulder

2. Introduction Colorado’s aspen trees Why are they cool? ( trekkerphoto.com )trekkerphoto.com

3. How are they Special? Winter photosynthesis in their bark Share a common root structure Deciduous Live in the sub alpine

4. Does chlorophyl content in the bark of Aspen trees differ within the winter depending on available sunlight ? (Barr and Potter, 1974) What induces the chlorophyl with in the bark and why? Prior studies indicated bark chlorophyl content is relative to age (Barr and Potter, 1974) Chlorophyl In the Bark

5. Why is This Important Potential for New habitat Loss in Bio Mass Better understand Species

6. Hypothesis If winter chlorophyl production within Populus tremuloides is dependent on photoperiod than the aspect of the tree will also affect the amount of chlorophyl produced.

7. Location

8. Methods Visually documented trees on Northerly and Southerly aspects When selecting location and specific trees I paid special attention to; elevation temperature size of tree Take photographs of trees

9. Methods

10. Results

11. Discussion Potential flaws Is aspect related to Chlorophyl concentration? Other variables Human error Is it more closely related to the thickness of a stand?

12. Conclusion Not significantly related to aspect Other shading factors appear to be more influential. Any other Questions?

13. Resources Halfpenny, James. Winter An Ecological Handboobook. Johnson Publishing, Boulder, CO. 1989 Marchand, Peter. Life in the Cold. University Press of New England, 1996 Barr, M. Potter, L. Chlorophylis and Carotenoids in Aspen Bark (Populus tremuloides). The Southwestern Naturalist, Vol. 19, No. 2 (Jul. 26, 1974), pp. 147-154

16. My Study