Habitat Management and Fire by TR Michels
Fires, whether from natural causes such as lighting, or caused by humans (intentionally or unintentionally) on prairies and meadows, and in brushy areas and forests, have been part of the natural process of plant regeneration for centuries. Even naturally caused wildfires can be beneficial as they reduce natural fuels, which in turn reduce the chances of wild fires in the near future. Wildfires also expose mineral soil for seedbeds for regeneration of wind-disseminated species, such as fungi, mosses, grasses, forbes and many tree species. The reduction in vegetation in turn helps in the control of insects, diseases, and competing vegetation. As a result these wildfires often result in the improvement of natural ecosystems and wildlife habitat as varied as wetlands, prairies, brushy areas and forests.
Native Americans often deliberately set fires to clear the land for horticulture, to improve access to some areas, and to change the composition of the plant community to attract game animals (such as bison). Early settlers set fires to assist in preparing the soil for agriculture and to eliminate stubble from the fields in the fall.
However, because of the destruction of human life, property, and resources by wildfires, the general government policy for most of this century has been to utilize man-made fire for the suppression of wildfires. The use of media campaigns such as Smokey the Bear, and Bambi fleeing from a fire, combined with fire suppression practices has resulted in a build up of vegetative fuels in many areas. Fire ecologists expect it will take several years of wildfires to establish a natural fire regime in many ecosystems.
In some areas where fire has been prevented from conducting its natural role in the environment, private and governmental agencies and scientists are setting controlled fires to mimic natural fire and improve landscape health and community safety. “One of the hard lessons we’ve learned is that eliminating or suppressing all fires actually increases the risk to people, damages natural habitats and drives up fire fighting costs” said Susan Harris, state director for the Nature Conservancy of Missouri.
Years of forest management practices that have eliminated wildfires has resulted in many forests becoming choked with thick undergrowth and small trees, that naturally occurring fires would normally eliminate. After years without fire, these forests become tinderboxes that are prone to hotter burns that are harder to control and pose a greater risk to communities than normal. These intense fires can have the ability to severely damage plant and wildlife species.
The Benefits of Fire
Many plant and animal species need fire to reproduce and thrive. Plants that need fire to reproduce and thrive are referred to as “burn-species”. Some of the “burn species” plants are ephemeral annual herbs and forbes that have found an unusual means of adapting to environments that are for the most part unfavorable to their survival.
In the first year after a fire has temporarily diminished dominant forms of vegetation these herbs and forbes may appear and flourish, and upon maturation, they leave their seeds behind. Although these plants may disappear from the landscape within a few years of a fire, the seeds can remain viable for up to 100 years or more. The goal of the seeds is to re-colonize the area after another fire. The plants may also appear from time to time in areas disturbed by other means, such as along sections of recently cleared trails, on land slides, and even along the areas of new road construction.
White-tailed deer, doves, quails, turkey, sharp-tailed grouse and prairie chicken are game species that benefit from prescribed fire. Habitat preferences of several endangered species, including the Florida panther, gopher tortoise, indigo snake, and red-cockaded woodpecker, are also enhanced by burning. The benefits to wildlife from fires can be substantial; fruit and seed production is often stimulated; herbage, legumes, and browse from hardwood sprouts may increase in both quality and quantity; and openings are created for feeding, travel, and dusting.
After years of fire suppression in many areas, land managers now have to go back and ignite fires to mimic the natural fires these species depend on. Prior to settlement by the Europeans, occasional fires were an integral part of many ecosystems, and native plants and animals had adapted to the occurrence of wildfires. Forests were a more varied blend of old and young trees and some forests were more open in character. Fire recycled the nutrients of the dead wood for use by growing plants, and conditioned the forest floor for the regeneration of species that are dependent on disturbance of the forest floor.
Pine trees of many species are a prime example of species that benefit from fire. During high intensity burns, the sealed cones of many pines open up, allowing dispersion of seeds over the fire-cleared ground. Anyone who has visited Yellowstone Park since the latest wildfires there has seen the abundant re-growth of not only the pine trees, but of many grasses, wildfires and shrubs; which have provided new habitat for many species of birds and mammals. In many areas pine trees are failing to regenerate due to past fire control practices.
The federally endangered Red-cockaded Woodpecker is a fire-dependent species. It nests only in mature pine trees that are free of surrounding underbrush. Researchers believe the Red-cockaded Woodpecker colonies in many areas have been abandoned because the sites have become too brushy. Periodic fires would control the brush, which may provide predators with access to woodpecker nests.
Entire ecosystems often need fire to maintain their natural diversity of plants and animals. Many pine-oak, oak forests and oak savannahs have poor reproductive success without occasional fires. Little or no oak regeneration has occurred in some areas as a result of fire suppression. Oaks provide acorns in the fall, which are an important food source for black bear, white-tailed deer, turkey, and other wildlife.