Query FIA Tips

Tips for querying the FIA database:

• SURVEY.ANN_INVENTORY = "Y" - selects only those surveys done using the modern, standardized methodology

• PLOT.PLOT_STATUS_CD = 1: Sampled - at least one accessible forest land condition present

• PLOT.KINDCD > 0 AND < 4: Standard National Design plots - basically NOT 0 (Periodic inventory plot - pre 1990s, non standardized) AND NOT 4 (Modeled periodic inventory plot - conducted only in Northeat and North central regions)

• PLOT.DESIGNCD = 1 or 220 or 240 or 311 - 314 or 328 or 502-505 - all basically sampled the same way (see Appendix B of Phase 2 documentation for explanations)

• PLOT.QA_STATUS = 1: Standard production plot

• PLOT.MANUAL >= 1: limits data to those collected using the standardized methodology described in the National FIA Field Guide

• PLOT.SAMP_METHOD_CD = 1: Field visited (as opposed to 2 = remote sensed) PLOT.INVR < 9999 (INVYR is set to 9999 to distinguish those Western Phase 3 plots that are “off subpanel”. This is due to differences in measurement intervals between Phase 3 (measurement interval=5 years) and Phase 2 (measurement interval=10 years) plots. Only users interested in performing certain Phase 3 data analyses should access plots with this anomalous value in INVYR.)

• COND.TRTCD1, TRTCD2, and TRTCD3 = 00: No observable treatment (i.e., no cutting, girdling, herbicides, etc.), but most records are actually NULL in these fields

• COND.STDORGCD - Stand origin code - 0 = Natural stand (vs. 1 = clear evidence of artificial regeneration)

• TREE.STATUSCD = 1 - live trees

• PLOT.STATECD, UNITCD, COUNTYCD, and PLOT should be used in concert to uniquely identify a plot, but the documentation confusingly states that "Along with STATECD, INVYR, UNITCD, COUNTYCD and/or some other combinations of variables, PLOT may be used to uniquely identify a plot."

Source: http://ecologicaldata.org/wiki/forest-inventory-and-analysis-database