Item 2: Ordinance on West Eugene Wetlands Burn Ban Exemption

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incumbent upon the burn boss to ensure that a controlled burn is conducted under appropriate conditions. Fire managers use computer models to predict fire behavior given certain site conditions, and under specific weather conditions. These models are used to determine the appropriate range of temperatures, humidity, and wind speed under which a burn can be safely conducted. For each controlled burn, a burn plan is prepared that states the conditions under which the controlled burn can be safely carried out, and if those conditions are not met, the burn is postponed until a later date. The burn plan also specifies the crew and equipment needed, and the pattern by which ignition will occur. Safety is also bolstered by providing appropriate fire breaks that are mowed or plowed around the burn unit to help contain the fire within the desired area The main drawback of controlled ecological burns from the point of the general public is the smoke that is generated. While a controlled burn may resemble a grass field burn, the amount of smoke produced by a controlled burn in a native prairie is much less than a burn of an equal area of grass seed field. This is because the amount of fuel present in a grass seed field is 2 to 4 times greater per unit area than in a native prairie. Controlled burns in Eugene are only conducted when the prevailing wind blows the smoke away from the populated urban areas, and under atmospheric conditions that provide for the most efficient dispersal of smoke. Weather conditions are monitored continuously during a burn to ensure prevailing winds remain appropriate during the entire ignition period. Similarly, burn units are typically smaller than grass seed fields which mean that the actual length of time during which the burns occur is quite short and the amount of fuel burned during an event is generally less than typical grass seed field burns. 4. Alternatives to Controlled Ecological Burns A number of alternatives to controlled ecological burning have been proposed, but none appear to provide all of the ecological benefits of fire. Mowing can inhibit the growth of woody plants and maintain the open prairie aspect. Mowing also may improve habitat for some of the rare prairie species, if it is done at the proper time of year. For example, the Bradshaw's lomatium population in Amazon Park has greatly increased in size over the past 15 years since the first mowing has been delayed until the plants have finished growth and the seeds have matured. At the plant community level, as noted above, mowing was found to provide ecological benefits in wet prairie, but not as extensive as the benefits of controlled burns. However, mowing large acreages can be expensive, and wet prairies typically have a very irregular surface with numerous divots, hummocks, and ant mounds that make equipment operation difficult. Mowing may promote the growth of invasive non-native grasses such as tall fescue (Festuca arundinacea). Mowing also does not provide the nutrient cycling benefits or microhabitats suitable for seedling germination that fire provides. Manual labor can be used to remove woody plants that have invaded prairie habitats. In fact, at Willow Creek we have determined that manual removal is necessary to achieve our management goals because the ash and pear trees are too well established to be removed by fires occurring on a 2 to 5 year interval. Removal of woody plants also reduces the amount of fuel that the fire d d 5