Table 3.

Tree variables collected for UFORE analysis with associated reason for data collection

Tree IDUnique tree number
Distance (ft/m) and direction (degrees) from plot center or TMPzUsed to identify and locate trees for future measurements; TMP is tree measurement point (Table 1)
Species codey (A, C, E, S, V)Species code from standard list currently containing over 10,000 tree and shrub species
Number of dbhs recordedyFor multistemmed trees
Dbhy (C, S)Diameter at breast height (in/cm) for all recorded stems
Dbh measurement heightRecorded if dbh is not measured at 1.37 m (4.5 ft)
Total heighty (A, C, E, S, V)Height to top of tree (ft/m)
Height to crown basey (A, S, V)Height to base of live crown (ft/m)
Crown widthy (A, S, V)Recorded by two measurements: N-S (north–south) and E-W (east–west) widths (ft/m)
Percent canopy missingy (A, S, V)The percent of the crown volume that is not occupied by leaves; two perpendicular measures of missing leaf mass are made and the average result is recorded; recorded to nearest 5%
Diebacky (C,E, S)Percent crown dieback to nearest 5%
Percent impervious beneath canopy (H)Percent of land area beneath entire tree canopy’s drip line that is impervious
Percent shrub cover beneath canopy (H)Percent of land area beneath canopy drip line that is occupied by shrubs
Crown light exposurey (C, S)Number of sides of the tree receiving sunlight from above; used to estimate competition and growth rates
Distance (ft/m) and direction (degrees) to space-conditioned residential buildingsy (E)Measured for trees at least 6.1 m (20 ft) tall and within 18.3 m (60 ft) of structures three stories or less in height
Street treeY/N; used to estimate proportion of population that is street trees
Tree statusIndicates if tree is new or removed from last measurement period
  • zRequired for permanent reference of plot.

  • yRequired for UFORE analysis.

  • Variable used to assess: A = air pollution removal; C = carbon storage/sequestration; E = energy conservation; H = hydrologic effects; S = structural information; V = VOC emissions.

  • UFORE = Urban Forest Effects.