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Prairie Establishment and Maintenance
TThe prairie ecosystem is the main focal point of the learning experiences offered by the AELC. Prairies have an abundance of plants, insects, birds, mammals, and reptiles, many of these found only in prairies. Prairie grasses provide excellent cover for wildlife because they hold up well under severe winds, snow, etc. Beginning in about 2004 with a the first planting, we in cooperation with the MN DNR, AURI and Kaste Seed Company, began implementing a plan to replace the Bromus and Quack grass in three areas with a mixture of prairie grasses and forbs. The second planting was completed in 2010 and a third in 2011 and 2012. The grasses and forbs also provide seed and nectar for insects, butterflies, birds, and small mammals. But to get these benefits, fire must occur to restore the prairie.
Managing prairies with prescribed burns has many benefits. Unburned prairies leave a layer of dead and decaying vegetation. This stifles the growth of the prairie plants and deprives plants of space and light.
The first established prairie has been burned regularly since the seeded plants matured. The Minnesota Department of Natural Resources and The Nature Conservancy have planned and carried out the prairie burns. First they study their records and the sites to see what areas need to be burned and are feasible to burn during the upcoming spring season. Next they create burn plans which layout firebreaks, points of concern, what weather conditions would create the "perfect" burn conditions, number of people needed, and equipment needs.
Stopping Sand Dune Succession
A few thousand years ago the Sand Hill River emptied into glacial Lake Agassiz at a site that is now the AELC. After the lake drained to the north, the river delta sand developed into dunes.. Soon after the sand became a dry environment, plants invaded the area. On these dunes of sand, primary succession began to occur, with small grass-type species (the pioneer species) quickly dispersed into the open sand. The roots of these plants helped to stabilize the soil and made it possible for other plants to grow there, leading to the formation of the grass or wooded climax community.
Sometimes, (probably often), things will happen to disturb these plants. For example, a good wind may come and blow lots of sand to cover them/a storm may come/etc., and this would then result in open sand again. During the last 50 years nearly all open-sand areas have disappeared through succession. The open sand areas are excellent education-sites and professional advisors have recommended that efforts to keep a couple open be a part of the ALEC Strategic Plan. Three rare plants are found on the margin of the Death Valley open sand; this is the only recorded location of these plants in NW MN.
The successional process can be restricted by removing invading woody plants and opening adjacent areas to more wind-action. The action-plan in the Death-Valley has been to remove the invading Creeping Juniper and cutting down large trees in the path of the prevailing winds. The keeping sand-areas open requires ongoing management.
Oak Savanna Management
AELC’s purpose is to “foster a greater awareness of the interrelationships between humans and nature”. Providing outdoor natural resources conservation programs to audiences of all ages. There are lots of degraded oak savannas in the region. Most of these savannas were grazed but were never plowed or logged. Often many of the original open-grown bur oak trees are still present, usually on the ridge tops, but sometimes in the draws or on the south-facing slopes. If the savanna was fairly far from the farmstead, it may not even have been heavily grazed.
>Oak savannas are fire-dependent ecosystems and fire is an essential element in their establishment and management. There are two kinds of fires in ecosystems: wildfires and prescribed fires. Wildfires are those that have started spontaneously, generally by lightning. Prescribed fires are those set by land managers to bring about desirable changes in ecosystems and are based on a written plan, the burn prescription. During the past 50 years and especially from 1991 to 2009 grazing and burning did not take place in the AELC oak savanna areas. The lack of fire has resulted in several plant types invading the savannas; these invaders have begun to change savanna structure and character.
The Minnesota Department of Natural Resources and Nature Conservancy have a developed plan of burning the AELC oak savannas. We are dealing here only with prescribed fires.