Enhanced Fujita scale damage indicators and degrees of damage, chapter 27

C-2 Trees (C-T)

Typical Species:

Hardwood: Oak, Maple, Birch, Ash, Beech, Cherry, Hickory, Walnut, Aspen, Elm, Poplar
Softwood: Pine, Spruce, Fir, Hemlock, Cedar, Larch, Redwood, Cypress

Notes:

General differences in the responses of softwood and hardwood species are less important than other factors
Decrease toward lower-bound wind speed if trees show evidence of significant rot, or if uprooting occurs with saturated ground or very shallow soil
In urban / suburban areas, trees broken at base of trunk were likely planted too deeply, had mechanical injury or had girdling roots - decrease toward lower-bound wind speed
For forests and woodlots composed of even-aged monoculture plantations, decrease toward lower-bound wind speed; for forests or woodlots composed of mature, deep-rooted red oak, red maple, beech, hemlock or white cedar, increase toward upper-bound wind speed
Increase toward upper-bound wind speed if there are no leaves on trees (e.g., spring or fall)

Table 27. Degree of Damage (DOD) for Expected (EXP), Lower Bound (LB) and Upper Bound (UB)
DOD	Damage Description	EXP*	LB*	UB*
1	Small limbs broken (less than 2 cm diameter)	70	55	85
2	Large branches broken (2-8 cm diameter)	90	65	110
3	Up to 20% of mature trees snapped and/or uprooted	115	80	150
4	More than 20% of mature trees snapped and/or uprooted	150	105	190
5	More than 50% of mature trees snapped and/or uprooted	190	145	230
6	More than 80% of mature trees snapped and/or uprooted; numerous trees may be denuded/debarked by missiles with only stubs of largest branches remaining	235	190	275

*All wind speeds in km/h