Tree ring growth and 13 C/12 C isotope compositions have frequently been used as a climate proxy to analyze the paleo atmosphere. The effect of carbon dioxide can be seen by analyzing both the tree ring width and the carbon isotope composition (Stuiver & Quay 1984). In this study we test the validity of previous assessments that plants can serve as pCO2 indicators (McCarroll & Loader 2004, Cui & Schubert 2016). This record of change over time will identify the effects anthropogenic climate change can have on the carbon isotope signature of these Bogus Basin trees. Creating a standard for the localized Boise area allows for future isotope analysis of Central Idaho to have a pre-existing record to compare to. Since we are examining atmospheric variability in the Boise Foothills, samples would all be collected from a localized area from Ponderosa Pines at relatively similar elevations.