Flammability of native understory species in pine flatwood and hardwood hammock ecosystems and implications for the wildland–urban interface

Six understory species from five pine flatwood sites and six understory species from five hardwood hammock sites were harvested for biomass analyses to compare potential flammability between two ecosystems in the south-eastern coastal plain of the United States. Plant components were separated into live and dead foliage, accumulated litter on and under the plant, and small and large stems. Foliar biomass was further analysed for moisture content, volatile solid content, and energy content. Statistical analyses revealed differences among species and between ecosystems. Serenoa repens plants present a wildfire hazard because they contain greater biomass than other species studied. Ilex glabra and Lyonia ferruginea are also hazardous to wildland–urban interface (WUI) structures because they have greater foliar energy content than other species studied. Callicarpa americana plants present the least wildfire hazard to WUI structures. We conclude that differences in flammability among species exist, but the causes of flammability are different among species. In addition, species in the same genus do not always have the same flammability. Based on measured characteristics, understory plants in pine flatwoods have greater ignitability, sustainability and combustibility than understory plants in hardwood hammocks. However, the measurements for consumability were similar between ecosystems.

[1]  E. H. T. Mak.  Measuring foliar flammability with the limiting oxygen index method , 1988 .

[2]  William J. Bond,et al.  Kill thy neighbour: an individulalistic argument for the evolution of flammability , 1995 .

[3]  C. Philpot,et al.  Influence of Mineral Content on the Pyrolysis of Plant Materials , 1970 .

[4]  Benjamin Kerr,et al.  Genetic niche‐hiking: an alternative explanation for the evolution of flammability , 2002 .

[5]  I. Noble,et al.  The Fire and Flammability Niches in Plant-Communities , 1995 .

[6]  J. Francis.  Comparison of Hurricane Damage to Several Species of Urban Trees in San Juan, Puerto Rico , 2000, Arboriculture & Urban Forestry.

[7]  R. Susott.  Differential Scanning Calorimetry of Forest Fuels , 1982 .

[8]  K. R. Montgomery,et al.  Effect of Leaf Thickness on Ignitibility , 1971 .

[9]  J. Rodríguez-Añón,et al.  Energetic Evaluation of Biomass Originating from Forest Waste by Bomb Calorimetry , 2001 .

[10]  M. Owens,et al.  Seasonal Patterns of Plant Flammability and Monoterpenoid Content in Juniperus ashei , 1998, Journal of Chemical Ecology.

[11]  Hans Lambers,et al.  Plant Physiological Ecology , 2000, Springer New York.

[12]  B. V. Wilgen,et al.  The role of vegetation structure and fuel chemistry in excluding fire from forest patches in the fire prone fynbos shrublands of south africa , 1990 .

[13]  J. Kirkpatrick,et al.  The flammability and energy content of some important plant species and fuel components in the forests of southeastern Tasmania , 1985 .

[14]  R. L. Myers,et al.  Ecosystems of Florida. , 1991 .

[15]  L. Trabaud,et al.  Structural characteristics of fuel components of five Meditarranean shrubs , 1990 .

[16]  D. Hartnett,et al.  Pine flatwoods and dry prairies , 1990 .

[17]  D. Schwilk.  Flammability Is a Niche Construction Trait: Canopy Architecture Affects Fire Intensity , 2003, The American Naturalist.

[18]  Thermogravimetric analysis of Mediterranean plant species , 2001 .

[19]  C. S. Wright,et al.  Foliar moisture content of Pacific Northwest vegetation and its relation to wildland fire behavior , 2002 .

[20]  Stephen C. Bunting,et al.  Seasonal Variation in the Ignition Time of Redberry Juniper in West Texas , 1983 .

[21]  James K. Brown.  Ratios of surface area to volume for common fine fuels. , 1970 .

[22]  M. Arthur,et al.  Effects of prescribed fire on canopy foliar chemistry and suitability for an insect herbivore , 2002 .

[23]  Patricia L. Andrews,et al.  Introduction to wildland fire, 2nd edition revised , 1996 .

[24]  A. W. Küchler.  Potential Natural Vegetation of the Conterminous United States , 1965 .

[25]  B. Oswald,et al.  The Southern Forest: Geography, Ecology, and Silviculture , 1999 .

[26]  E. A. Macie,et al.  Human influences on forest ecosystems: the southern wildland-urban interface assessment: summary report , 2002 .

[27]  A. Mallik.  Autecological response of Kalmia angustifolia to forest types and disturbance regimes , 1994 .

[28]  B. W. Wilgen,et al.  Fire and Plants , 1995, Population and Community Biology Series.

[29]  Robert W. Mutch,et al.  Wildland Fires and Ecosystems--A Hypothesis , 1970 .

[30]  S. B. Jones,et al.  Native Shrubs and Woody Vines of the Southeast : Landscaping Uses and Identification , 1989 .

[31]  W. Degroot,et al.  Effective Heat Content of Green Forest Fuels , 1977 .

[32]  David Kelly,et al.  The Florida palm coast fire: An analysis of fire incidence and residence characteristics , 1987 .

[33]  F. Albini,et al.  Predicting fire behavior in palmetto-gallberry fuel complexes , 1978 .

[34]  H. E. Anderson,et al.  Forest fuel ignitibility , 1970 .

[35]  Martha C. Monroe,et al.  Wildland Fire in the Southeast: Negotiating Guidelines for Defensible Space , 2003 .

[36]  R. Susott,et al.  Chemical composition of forest fuels affecting their thermal behavior , 1986 .

[37]  James K. Agee,et al.  Heat content variation of interior Pacific Northwest conifer foliage , 2002 .

[38]  J. R. Añón,et al.  Calorific values and flammability for forest wastes during the seasons of the year. , 1995 .

[39]  R. Fonda.  Burning Characteristics of Needles from Eight Pine Species , 2001 .

[40]  Patricia L. Andrews,et al.  Introduction To Wildland Fire , 1984 .

[41]  D. Teketay,et al.  Response of plant communities to fire in an Acacia woodland and a dry Afromontane forest, southern Ethiopia , 2003 .

[42]  J. K. Gilless,et al.  The defensible space factor study: a survey instrument for post-fire structure loss analysis , 1991 .

[43]  R. Susott.  Characterization of the thermal properties of forest fuels by combustible gas analysis , 1982 .

[44]  Reggie E. Thackston,et al.  Chemical Composition of Mountain-Laurel Kalmia Leaves from Burned and Unburned Sites , 1982 .

[45]  T. Hinckley,et al.  CHAPTER 3 – TEMPERATE HARDWOOD FORESTS , 1981 .

[46]  P. Rundel.  Structural and chemical components of flammability [Fire adapted plant species, evolution, canopy structure, includes forest trees, grasses, shrubs] , 1981 .