The Ecology and Management of Prairies in the Central United States

11. Restoration

Sometimes a prairie is missing plant species, and not even top-notch prairie management can bring them back. If your prairie is near other prairies where those species exist, they may come back on their own. Otherwise, if the species are important enough, it might be necessary to bring seed in yourself to get them established. In more severe cases, you may have cropland, tame pasture, or some other complete conversion of a prairie to restore. There are other books besides this one that will provide comprehensive information on prairie restoration, particularly related to the reseeding of cropfields, and some of those are listed in the appendix. However, the following information can help to get you started. Seed Sources Establishing new plant species from seed is usually the best option. Transplanting mature plants from other sites can sometimes work as well, but that means that you are removing plants from somewhere else, which is usually not a good idea. A third option is to combine the first two options by obtaining seed and growing them into plants in a greenhouse and then transplanting those plugs. There are basically two ways to obtain seed; buy it or harvest it yourself. Either way you go, there are important guidelines that relate to the origin of the seed you obtain. prairie management 11. Restoration 162 prairie management If you are adding plant species to an existing prairie or reseeding a cropfield near an existing prairie, you need to think carefully about the genetic implications . Bringing in new genetic material and allowing it to intermix with the genes of existing plants can carry risk, although the level of that risk is still poorly known. For example, let’s say you live in eastern Minnesota and want to do a cropfield restoration project near a prairie. You can go to a nearby seed company and buy seed for a number of native grasses and wildflowers. However , you may not be able to learn the actual geographic origin of the seed you buy. Taking one species, purple prairie clover, as an example, let’s assume the seed you buy to plant in Minnesota was originally harvested from a prairie in central Kansas. When you plant seed with genetic material adapted to Kansas you are taking several risks. First, there is the risk that the plants will not be able to survive in eastern Minnesota. The climate and soils may both be very different from the conditions to which the Kansas prairie clover is adapted. Also, prairie clover in Kansas begins growing and blooming considerably earlier in the year than prairie clover in Minnesota. Yours might now bloom early enough that it misses important pollinators that haven’t yet emerged, or even worse, it might begin growing so early that it gets killed in a late freeze. The second risk of moving Kansas seed to Minnesota is that if it does survive, its pollen could spread to other prairie clover plants that are locally native to eastern Minnesota. If that happens, it’s possible that the genetic information from Kansas could intermingle with that from Minnesota and create prairie clover plants that are no longer as well adapted to Minnesota conditions. Now, you may have hurt not only the prairie clover in your own prairie, but also decreased the chances of survival for the prairie clover that was already in the nearby landscape. The data to support the level of risk from moving nonlocal seed into an area are still inconclusive, particularly on the issue of genetic pollution from outside sources. There are numerous examples of seed from faraway origins failing to survive under local conditions; that happens most often when seed is transported north or south. But whether or not nonlocal seed can pollute the genetics of local populations is still being hotly debated. The other possibility , of course, is that the added genetic information could actually strengthen 163 restoration the genetic diversity of the population and increase its fitness and resilience. However, it seems reasonable at this point to follow the safe route, and use seed obtained from sources as close to your planting site as possible. Another risk you may encounter when buying seed is ending up with species that are not actually natives. A number of commercially available wildflower mixes contain species that are either nonnative or naturalized (naturalized generally means that a species is nonnative, but seems to be well...