Implementing a regional phenology network: The California Phenology Project

Background/Question/Methods

The California Phenology Project (CPP) was established in 2010 to develop and test monitoring protocols and infrastructure to support a long-term plant phenological monitoring program in California.  The CPP is in its second year of data collection and has established over 100 sites in seven pilot National Park units (Santa Monica Mountains NRA, Joshua Tree NP, Golden Gate NRA, John Muir NHS, Sequoia and Kings Canyon NPs, Lassen Volcanic NP, and Redwood NP). These parks represent a range of desert, mountain, and coastal ecosystems.  In 2011, the CPP monitored over 650 individual plants across the seven pilot parks, recording over 10,000 observation records and over 70,000 phenophase records.   These phenological records will improve our understanding of how plants respond to environmental variation and ultimately inform decision-making by natural resource managers.  

Results/Conclusions

Here, we present three preliminary examples of how these records can be used to describe the relationship between phenological patterns and environmental variation at different spatial scales.  First, we present leaf phenology data for the widespread tree species, Populus tremuloides, and demonstrate how data collected in California relate to patterns across the United States.  Second, we show how flowering phenology of the chaparral shrub Baccharis pilularis varies along a latitudinal gradient within California. Finally, we show how flowering of the desert shrub Larrea tridentata varies along an elevation gradient within one park.  Based on these data, we also identified phenophases that may be particularly useful or problematic for each species, allowing us to refine monitoring efforts for the second year of data collection efforts. These preliminary results will allow the CPP to identify gaps in current monitoring efforts and to better direct future monitoring resources on both temporal and spatial scales. Importantly, these data provide baseline information on plant phenological patterns which we will use to gauge future phenological change.