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Ramsey County Multi-Hazard Mitigation Plan, 2018 Page | 91 impact. While wildfires are necessary for healthy ecosystems, they burn whatever fuel is in their path, whether vegetation or buildings. One of the most common causes of a home being damaged or destroyed is due to radiant heat. In a wildfire, radiant heat is the heat given off by burning vegetation. The high temperatures of some wildfires can cause the deck, siding, or roof of a home to ignite, because the fire was too near the home. Studies in western wildfires have shown that approximately 85% of homes surviving a major wildfire had 30-50 feet of defensible space around them, coupled with fire-resistant roofing. Approximately 1,600 wildfires occurred each year in Minnesota on average from 1976-2011 (MN DNR, 2011). Wildfires occur throughout the spring, summer and fall, however, most wildfires in Minnesota take place in March, April, and May. During this period, much of the existing vegetation has been killed due to winter temperatures and is dead, brown and combustible. Also, there is little green vegetation to serve as a barrier for a moving wildfire. Wildfire History in Ramsey County The Minnesota DNR responded to 13 wildfires in Ramsey County between 1985 and March of 2017, all of which were human-caused, burning a total of 120 acres. These include fires not only on state lands, but also rural private lands for which there is not another agency with primary responsibility. Wildfires that are not included in this data are those that occur on federal lands and those that are responded to by local fire departments. The largest fire burned 27 acres in 2008 in Vadnais Heights. Its cause was the burning of piled debris. These fires are mapped in Figure 21. The second largest fire occurred on April 6, 2000, burning 25 acres between North Oaks and White Bear Lake. The cause of the fire was due to arson. The only other notably large fire burned through 20 acres of Little Canada. The cause of the fire was from arson as well. According to MN DNR data, there are 6,366 acres of peat in Ramsey County. Peat is partially decayed plant matter found in ancient bogs and swamps. Minnesota has approximately 6 million acres of peatland, the highest total acreage in the contiguous United States. Peat fires are deep-rooted fires that burn underground, lasting for weeks, months, or even years. They can smolder during winter months beneath the snow, surfacing again in the spring to burn above ground. Peat ignites when its moisture content is low, and then it supports combustion rather than flame. Once started, combustion is persistent because peat contains oxygen and needs little or no outside oxygen to continue burning. Peat’s insulating qualities mean the fire loses little heat. As the peat dries, it becomes water repellent. These factors result in long-lasting fires that require extensive operations to extinguish. However, peat fires have not been an issue in Ramsey County. Wildfire has been ranked as a low hazard for the purposes of this plan. Wildfire and Climate Change Temperatures are predicted to rise in the state, which could lead to more extreme heat events and associated wildfire risks. As Minnesota’s climate changes, weather fluctuations between drought and extreme rain events and increasing temperatures will result in changes to forest composition and/or