The Prairie Farm
Spring-Summer 2008
Wetlands
Two of six wetlands undergoing restoration were planted with plugs of prairie cordgrass (Spartina pectinata) started and grown under greenhouse conditions in winter and spring of 2008. Plugs were planted June-July, 2008, in two densities (3 and 5 foot centers) in each wetland to compare the time and cost required to establish a dense, closed stand of cordgrass. Approximately 4,000 plugs were planted in each of the approximately 1.5 acre wetlands. Survival rate of the cordgrass plugs measured at the end of the 2008 growing season was high, approximately 90 percent. Many plugs flowered and tillered vigorously the first year. Most other wetland species that grew together with cordgrass the first year were common annual grass or grasslike plants present in the seed bank, such as barnyard grass (Echinochloa) and nut sedge (Cyperus). River bulrush (Schenoplectus), a common early-successional perennial wetland plant, also grew with cordgrass in the deeper parts of the basin.
The largest wetland restored is approximately 12 acres in size at full pool. A water control structure was built into the plug to allow adjustment of water depth, hydroperiod and vegetation composition and production. Many hundreds of ducks used the wetland during spring 2008 migration. Breeding ducks and migrating shorebirds were abundant during summer 2008. A pair of American bitterns nested and raised young on the wetland as well. Native wet meadow plants such as sedges (Carex) and prairie cordgrass spread out in the wetland during its first functional year in many decades.
Expansion of native, wetland vegetation is a major goal of the Prairie Farm project. Numerous environmental benefits will result from this effort; however, the production and sale of wetland seed also represent a potentially significant income stream for the Prairie Farm. To further this goal, several wetland species (primarily sedges) were collected from natural, private wetlands and transplanted into restored wetland basins on the Prairie Farm in 2008. These transplants and others planned for the future will form the innoculum for our future native wetland seed business.
Grasslands
Nearly 100 acres of corn and soybean cropland on the Prairie Farm were planted to grassland in Spring 2008. One field was drilled to NE-28 switchgrass and another to a mixture of tall grasses and prairie forbs dominated by Bonilla big bluestem. Seed will be the main product from the switchgrass field, while specialty hay and lean, grass-fed beef will be the main product anticipated from the bluestem field. Seven acres of another field were sub-leased to South Dakota State University for a 3-year experiment, funded by the NRCS, to compare the production and soil quailty of corn, switchgrass, a bluestem mixture (including forbs), and prairie cordgrass. The remaining 13 acres of this field were drilled with Sunburst switchgrass. Good initial stands of grass were established in 2008.
CRP
Experiments were initiated in 2008 to renovate CRP at the Prairie Farm to enhance their potential to produce biofuel feedstock in the future. Permission to conduct these experiments on active-contract CRP fields was granted in 2007 by the South Dakota State FSA Committee and the South Dakota State Technical Committee. The primary objective is to convert cool-season invasive grasses and weedy forbs that currently dominate these fields with low biofuel value to warm-season, native grasses with high biofuel value. This will be accomplished by combinations of spring and fall burns, herbicide application, mowing, and grazing.
Fall 2007
The first stage of the Prairie Farm project began in fall 2007 when ditch plugs and low berms were installed in 6 drained wetland basins. Some 30 additional drained wetland basins remain on the farm and will be under consideration for restoration in the next several years. The adjacent figure shows the maximum extent of surface water in the Spring if all wetlands on the farm were restored to pre-drainage conditions. However, we think that nearly all wetlands, except the large, undrained semi-permanent wetland in the center of the farm, are temporary and seasonal in nature, and therefore, will dry out by early to mid summer in most years. In especially dry years, many of these restored basins will not have surface water at all. However, sub-irrigated conditions will be present in and near these restored basins to support wetland grass production throughout most growing seasons, even in relatively dry years.
