If you have watched the local news lately, you have likely seen many stories and warnings about wildfires in Lee and the surrounding counties. Certain precautions must be taken at the end of the dry season by everyone to prevent wildfires from breaking out, especially near residential areas. Although some wildfires occur from natural causes, most of the wildfires we hear about are caused by people either intentionally or unintentionally.
Fire is a natural part of our local ecosystems in south Florida. These pyrogenic ecosystems require occasional fire to keep vegetative communities in a natural state. These fires not only keep the vegetation in balance, but many forms of wildlife depend upon periodic fire to provide both habitat and food sources.
The plants in these ecosystems are adapted for fire and either overgrow and/or overtake other habitats when fire is suppressed. Our best example is the loss of the open canopy upland and wetland grasslands that once dominated Sanibel, as pictured here. This Spartina marsh is a pyrogenic ecosystem that is essential to wading birds, amphibians, aquatic insects, and the endemic and state-protected Sanibel Island rice rat (Oryzomys palustris sanibeli).
From the lack of periodic fire and the suppressing of wildfire over the last half-century or more, shrubby hardwoods have overtaken most of our open grasslands making most of the island look like a massive tropical hammock. This is why controlled burning (prescribed fire) is so important to keeping the remaining open grasslands intact.
The big difference between wildfire and prescribed fire is that a wildfire is either caused by uncontrolled natural events, such as a lightning strike, or by accidental or purposeful human actions without consent from the reigning fire agency. Rather, a planned fire is one that is performed by a certified burn boss and a trained crew that makes sure the fire stays within the prescription and is controlled.
To perform a certified controlled burn, a prescription must be written by a certified burn manager. In this prescription, the goals of the burn, areas to be burned, crew and equipment involved, safety precautions, possible smoke effects, contingencies, and the correct atmospheric conditions expected during the burn that fit the criteria to perform a burn must be submitted and accepted by Florida Forest Service before it can begin.
Prescribed fire is used to keep our native habitats healthy and for human safety due to reducing fuel loads (dead and overgrown vegetation) that could result in very large, strong fires that are hard to control.
The natural cycle of our area involved lightning strikes igniting natural wildfires in these pyrogenic areas right before the wet season begins, typically from April to July. This is when the vegetation is the driest and most likely to ignite. Residents and visitors in south Florida need to be very aware and cautious that they do not accidentally start these fires.
Here are some things you can do to prevent accidental wildfires:
Pictured above, saw palmetto (Serenoa repens) is a highly pyrogenic plant that actually has oils in its leaves to assist in periodic burning. Saw palmetto rebounds quickly after a fire has gone through from root crowns and rhizomes.
Pictured below, is the cabbage palm (Sabal palmetto), which is the state tree of Florida. It is adapted for fire and mostly survives periodic fires (large trees). The palm fronds are highly combustible and allow the fire to travel to nearby trees through the canopy.