FIRE PRONE PLANT CHARACTERISTICS

Many plants are particularly susceptible to fire.  Some plants ignite readily and burn intensely, and should be removed if present in a home's Defensible Space zone or close to roads and driveways.  Fire-prone plants typically share certain characteristics:

• They are often blade-leaf or needle-leaf evergreens.
• They have stiff, woody, small or fine, lacey leaves.
• Their leaves and wood often contain volatile waxes, fats, terpenes or oils (crushed leaves will have strong odors).
• Their sap is usually gummy, resinous and has a strong odor.
• They usually contain plentiful fine, twiggy, dry or dead materials.
• They may have pubescent (hair covered) leaves.
• They may have loose or papery bark.
• These plants flame (not smolder) when preheated and ignited with a match.

FLAMMABILITY & CONDITION

The condition of the plant is as important as its species. Even some fire-prone species can be quite fire-resistant if properly maintained.  Depending on its growth form and access to water, the same species may be fire resistant in one environment and flammable in another.  Water -stressed plants that are in poor condition are more likely to burn readily. Those species already identified as fire-prone become explosively flammable when poorly maintained.  South-facing slopes, windy areas, sites with poor soils and urban landscapes are more stressful for plants and lead to greater hazard from burning vegetation.

COMMON FIRE-PRONE VEGETATION TYPES

• Grasses: Any cured (dry) grass, including bamboo. Non-irrigated, annual grasses are typically more flammable than perennial grasses. Irrigated grasses are fire resistant.
• Perennials and herbs: Any dry or cured herb.
• Ferns: Any dry or cured fern, particularly bracken and sword ferns.
• Brush: Any brush with excessive deadwood. Any over-mature, dying or dead brush.
• Trees: Any forest, stand or urban forest that is over-dense, under stress, poorly maintained, or over mature.