%0 Research article
%T How well do U.S. Forest Service terrestrial ecosystem surveys correspond with measured vegetation properties?
%A Abella, Scott R.
%D 2011
%J Silva Fennica
%V 45
%N 4
%R doi:10.14214/sf.96
%U https://silvafennica.fi/article/96
%X Reliable estimates of species composition that forest sites are capable  of supporting – specific to ecosystem mapping units across landscapes –  are useful for many purposes in forest science and management. Like  forestry agencies in numerous countries, the U.S. Forest Service has  invested in ecological land classification (termed terrestrial ecosystem  survey [TES] in the study region of Arizona) that includes  ecosystem-explicit species lists taken to be estimated potential natural  vegetation (PNV). Using multivariate community analyses, PNV in the TES  was compared to measured species composition on 66 sites representing  among the least-disturbed vegetation (considered this study’s measured  PNV) spanning 11 ecosystem types on a Pinus ponderosa P. & C. Lawson  landscape in northern Arizona, USA. Agreement between the TES PNV and  measured species composition was lowest for forbs and shrubs (compared  to graminoids), and species composition differed significantly between  the TES and this study for at least one plant lifeform in 73% of  ecosystems. Reasons for differences between the TES and this study are  difficult to resolve, but in some cases appear to result from  identification of different species pools in the region. This study  suggests that the TES is a useful starting point in understanding  vegetation-environment relationships, but further work is needed to  refine species lists and more thoroughly account for the influences of  fire, grazing, and climate that can influence both PNV and current  vegetation. Refining and updating ecosystem-specific species lists may  benefit existing forest site classifications and could be planned for  when new site classifications are developed, especially with changing  climates.