The existing literature confirms that Native American tribes historically enhanced culturally preferred plant communities through periodic burning in what is today Yosemite National Park; in turn, beginning with nineteenth-century park development, fire suppression contributed to conifer and shrub encroachment on anthropogenic meadows and other culturally significant habitats. However, we contend that traditional burning practices cannot be understood without considering the pronounced cultural role of wetland habitats and species, and the intersection between burning practices and wetland plant communities among tribes of the Sierra Nevada Range. Our ethnographic investigations revealed that a majority of culturally important plants identified by tribal members in Yosemite Valley were wetland species. Interviewees also recall that traditional burning included wetlands and wetland margins – with the scale, timing, and location of burning responding to seasonal water-table fluctuations in those environments. Thus, US National Park Service (NPS) manipulation of valley hydrology eroded culturally significant plant communities over time, compounding the effects of fire suppression, together facilitating conifer encroachment. We present evidence of historical practices and trends based on a comprehensive review of available historical literature and ethnographic accounts, as well as the guidance of twentieth- and twenty-first-century tribal elders and the written record of NPS land management.

In order to assemble an ecological community it may be helpful to know not only how many parts there are, but what kinds of parts there are. Communities require at least two classification systems that provide simultaneous and somewhat contradictory lists of parts: phylogenetic and functional. These two classification systems can be arranged hierarchically so that many parts (species) are nested within a smaller number of groups (functional types). Even with objective classification techniques, it is difficult to know how many groups exist, and the number selected may be somewhat arbitrary. There does not seem to be a way to tell, a priori, how many functional types we can expect to find in a specified landscape or habitat. This raises difficult questions about the nature of fitness landscapes and the geometry of n-dimensional trait space.