Environmental Tolerances - key
Salt
low Cannot tolerate salt deposits on leaves
moderate Tolerates some salt on leaves but loses vigour with continual or frequent deposits
high Tolerates salt laden winds, salt spray and some salt build-up in groundwater

Wind
low Damaged by strong winds either from drying out or physical damage
moderate Tolerates strong winds or occasional gales. Will not grow well in persistent wind
high Little damage from strong to gale force winds

Drought
low Withstands only short periods (1-2 days) of mild moisture stress
moderate Can withstand seasonal droughts provided soil moisture doesn't drop below 'wilting point' for several weeks or more
high Can withstand seasonal droughts or semi-arid conditions

Frost (winter maximum)
low Damaged by cold winds or frosts of -2 or -30C
moderate Will tolerate frosts of -3 to -60C
high Frost hardy in lowland and lower montane areas. Will tolerate frosts of -70C or lower.

Waterlogging
low Cannot stand waterlogged soil for more than several days
moderate Can withstand frequent waterlogging but not continual waterlogging for more than several weeks
high Can stand roots continually in wet or waterlogged soil