Table 1.

Frequency of occurrence by biome of the top three most commonly encountered tree species in each city.

BiomeAverage frequency of occurrencezRange of average frequency of occurrencez
Tropical forest25.6    38–13
Broadleafed evergreen forest21.7    39–15
Deciduous forest36.4    56–13
Coniferous forest35.7    80–16
Mixed deciduous–coniferous forest40.4    59–27
Mediterranean woodland/scrub27.5    32–19
Savanna29.2    24–14
Grassland30.9    83–18
Desert40.9    71–16
Tundra55.0    91–6
Highland33.7    67–21
Average34.3    58.2–16.2

  • ↵zOf the three most commonly encountered street tree species in each city.