Arboriculture & Urban Forestry 33(2): March 2007 Arboriculture & Urban Forestry 2007. 33(2):83–97. 83 Hurricanes and the Urban Forest: I. Effects on Southeastern United States Coastal Plain Tree Species Mary L. Duryea, Eliana Kampf, and Ramon C. Littell Abstract. Several hurricanes struck Florida, U.S. in 2004 and 2005 causing widespread damage to urban and rural areas. We measured the impacts of five of these hurricanes on the urban forest and combined these results with four other hurricanes to present an assessment of wind resistance for southeastern United States coastal plain tree species. Urban forest loss was positively correlated with wind speed. Tree species demonstrating the highest survival in winds were sand live oak (Quercus geminata), American holly (Ilex opaca), southern magnolia (Magnolia grandiflora), live oak (Quercus virgin- iana), wax myrtle (Myrica cerifera), sweetgum (Liquidambar styraciflua), crapemyrtle (Lagerstroemia indica), dogwood (Cornus florida), and sabal palm (Sabal palmetto). In a statistical comparison of sand live oak, live oak, and laurel oak (Quercus laurifolia) survival after four panhandle hurricanes, laurel oak had significantly poorer survival than both live oak and sand live oak. Among all species, larger trees lost more branches than medium and smaller trees. Leaf loss had a positive relationship with survival; losing leaves during the hurricane meant higher survival. Trees growing in groups or clusters had greater survival than those growing as individual trees. Tree species with higher wood density had greater survival. Tree species categorized as having dense crowns lost more branches than those with moderate and open crowns; however, contrary to the literature, dense-crowned species survived best. A survey of arborists, scientists, and urban foresters ranked species for their wind resistance. Using our results from hurricane measurements and incorporating results from the survey and the scientific literature, we have developed lists of relative wind resistance for tree species in the southeastern coastal plain. These lists should be used with caution with the knowledge that no species and no tree is completely windproof. In addition, local considerations such as soil, cultural practices, tree age and health, and other urban forest conditions need to be taken into account. Key Words. Trees; tropical storms; urban trees; wind. In 2004, four hurricanes struck Florida with maximum sus- tained winds ranging from 169 to 233 km/h (105 to 145 mph). In 2005, Hurricane Dennis struck the Florida panhandle at 193 km/h (120 mph). The impacts of these five hurricanes were widespread ranging from urban areas to agricultural croplands to Florida’s natural ecosystems. Since 1992 when Hurricane Andrew struck south Florida, we have been study- ing the impacts of hurricanes on the urban forest (Duryea et al. 1996). We continued with measurements of hurricane wind damage to urban neighborhoods again in 1995 when two hurricanes struck the Pensacola, Florida, area (Duryea 1997) and then again in 1998 when Hurricane Georges crossed over the entire island of Puerto Rico. These nine hurricanes with their varied wind speeds gave us the oppor- tunity to study over 80 tree species and their comparable responses to hurricanes. This study reports on and synthesizes the types of tree damage, possible reasons for damage, and ways to avert damage in the future for southeastern coastal plain species in urban forests. Tropical and subtropical spe- cies are reported in a separate article in this issue. A considerable number of studies have investigated the effects of hurricane force winds on damage, mortality, and recovery of tree populations within natural forest ecosystems. In general, they have found that large trees (with large diam- eters and heights) experience more wind damage (Glitzen- stein and Harcombe 1988; Webb 1989; Walker 1991) and older forests are more damaged (Everham and Brokaw 1996). Several studies report that tree species respond differently with uprooting, stem breakage, or crown damage (Gresham et al. 1991; reviewed in Everham and Brokaw 1996). Everham and Brokaw rate 242 tree species from 47 studies for wind resistance in low- and high-intensity storms. When species are categorized according to conifers and dicots or by suc- cessional class (pioneer versus nonpioneer species), no clear trends are apparent. This lack of correlation with damage is also true for the influence of topography where damage ap- ©2007 International Society of Arboriculture
March 2007
| Title Name |
Pages |
Delete |
Url |
| Empty |
Search Text Block
Page #page_num
#doc_title
Hi $receivername|$receiveremail,
$sendername|$senderemail wrote these comments for you:
$message
$sendername|$senderemail would like for you to view the following digital edition.
Please click on the page below to be directed to the digital edition:
$thumbnail$pagenum
$link$pagenum
Your form submission was a success. You will be contacted by Washington Gas with follow-up information regarding your request.
This process might take longer please wait
