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events. Monitoring will determine the ultimate timing of the mows.Vegetation should be mowed to a height of 4-6 in, and the process repeated two or more times depending on the rate of growth throughout the season. During this time,weed species on the savanna edges and surrounding units can be treated by spot-spraying or mowing in order to prevent them from encroaching into the establishing prairie. In the second growing season,mowing is generally needed just once in the spring or early summer. However,spot-mowing and/or spot-spraying of problematic areas may be needed. Eventually,the prairie and savanna will need to be burned. Depending on the condition of the units,this will likely occur in the third or fourth growing season. Burning will help stimulate root production and aboveground growth, and will help to control woody and herbaceous species establishing in the savanna. Burning can be done in the spring or fall, depending on weather conditions and goals of the burn (controlling non-native grasses, etc.). However,because of the eagle's nest on the property,burns will likely have to occur in the fall.After the burn,native seed can be added to the units to supplement cover and diversity in areas that have not taken well. In the long term,a burn rotation will need to be established so that the units are burned at repeated intervals. For prairies,this can be once every 3-5 years. Burning every 5+years is a common interval in savannas,but can be hard on native shrubs. However,burning frequently will help to keep woody species (cottonwoods, boxelders etc.) from taking hold in the savanna. Ultimately,the interval length will depend on the desired balance of native shrubs and herbaceous plants,and can also be timed to respond to outbreaks of non-native woody or herbaceous species. If burning is not part of the management,the savanna will rapidly succeed to forest, since there are many woody seedlings (both native and non-native) encroaching from the surrounding units.The prairie and savanna units should be divided into 2 or more burn units that would be burned in different seasons or years to ensure the availability of unburned refugia for species.The current trails will serve as useful fire breaks,though multiple units can be paired for each burn. See the Prescribed Burning section below for more information (see Figure 13). Oak restoration The first priority for the savanna restoration is the establishment of herbaceous (and smaller woody) savanna species. Once the savanna has begun to establish, introduction of woody species,particularly oaks, can be considered.Very short woody plants such as leadplant and prairie rose will be introduced as part of the seed mix,helping to establish the 5-50% shrub cover typical of these savanna systems. Establishing the savanna canopy can come later,and will primarily include bur oaks.These can be planted in copses in the more open areas of the grassland. Bareroot seedling of other woody species, including chokecherry,hazelnut and wild plum can be added to the restoration to increase structural diversity once the herbaceous savanna species have established. For the wetter areas, dogwoods may Friends of the Mississippi River Bailey Point Nature Preserve NRMP 57