Tag : Grasses

Washington: Over the last decade, an average of over 61,000 wildfires have burnt 7.2 million acres per year in the United States. When a wildfire begins to expand, the firefighting work is complicated by challenges such as spot fires, which occur when winds lift lofted sparks and start new fires outside of the original fire perimeter. The greater the possible spot fire distance, the more difficult it is to monitor, control, and extinguish wildfires. A new study, led by University of Florida forest management researcher Victoria Donovan, found that as woody plants like shrubs and trees replace herbaceous plants like grasses, spot fires can occur farther away from the original fire perimeter. This "woody encroachment" is not only a major issue in grasslands where the study takes place, but also in wetland and savanna systems like longleaf pine, an important ecosystem in Florida. "Spot fires are one of the most common reasons why houses burn in a wildfire," said Donovan, an assistant professor with the School of Forest, Fisheries, and Geomatics Sciences at the UF/IFAS West Florida Research and Education Center in Milton, Florida. "It's not typically because the flames from wildfire reach a house, but that embers from that fire land on roofs, travel through home ventilation systems, or land on other combustible material on or near the home, and ignite the house from there. They're a big concern for structural damage." Donavan's study indicates that prescribed fire, which is commonly used in Florida to control woody plant growth, could help reduce spot fires. The study looked at three phases of woody encroachment: the first a largely grassland area, the second grassland with new forested growth, and the third a dense forest. The research wa ...