USA: Louisiana: The Duralde Cajun Prairie Restoration Project, Evangeline Parish

Project Stage:
Implementation

Start Date:
1994-07-26

End Date:
1994-07-26

Primary Causes of Degradation

Degradation Description

Today, substantially less than one percent of the coastal prairie remains. Although much of the former prairie has been converted to pasture for cattle grazing, the large majority has been destroyed for agriculture–sugarcane, grain crops and, in particular, rice. In Louisiana, the few remaining remnants of coastal prairie are narrow strips of land found along railroad rights-of-way. Most of these remnants are less than 30 meters wide, and the longest unbroken strips are only about 800 meters long. This extant prairie was either never tilled or has not been tilled since the railroad acquired the land ca 150 years ago.

The estimated total area of intact Cajun Prairie (i.e. coastal prairie in Louisiana) is only 100 acres (Allen and Vidrine 1989). This ecosystem is ranked G2 (imperiled globally because of rarity or because of some factor(s) making it vulnerable to extirpation) by the Nature Conservancy (Grossman et al. 1994), and in Louisiana it is ranked S1 (critically imperiled in state because of extreme rarity or because of some factor(s) making it especially vulnerable to extirpation from the state) by the Natural Heritage Program (Smith 1995). While agriculture and livestock have historically been the primary causes of degradation, development now poses the greatest risk to what remains of the coastal prairie, as most of the above-mentioned remnants are privately held, with only a small percentage preserved on government land.

Reference Ecosystem Description

Coastal Prairie vegetation is extremely diverse and dominated by grasses, including: Paspalum plicatulum (brownseed paspalum), Paspalum spp. (paspy grasses), Schizachyrium scoparium and S. tenerum (little and slender bluestem), Andropogon gerardii (big bluestem), Andropogon spp. (broomsedges), Aristida spp. (three-awn grasses), Eragrostis spp. (love grasses), Spartina patens (wire grass, near marshes), Panicum virgatum (switch grass), Panicum spp. (panic grasses), Sorghastrum nutans (Indian grass), Sporobolus spp. (dropseeds), and Tridens spp. (purple-top). Important sedges in the community include Carex spp. (caric sedges), Cyperus spp. (umbrella sedges), Rhynchospora spp. (beaked sedges), and Scleria spp. (nut-rushes). An abundance of forbs is present including Cacalia ovata (Indian platain), Helianthus mollis (sunflower), Liatris spp. (blazing-stars), Asclepias spp. (milkweeds), Silphium spp. (rosin-weeds), Petalostemum spp. (prairie clovers), Baptisia spp. (indigos), Amsonia tabernaemontana (blue star), Rudbeckia spp. (brown-eyed susans), Euphorbia spp. (spurges), Euthamia spp. (flat-topped goldenrods), Hedyotis nigricans (bluets), Ruellia humilis (wild petunia), Ludwigia spp. (water primroses), Coreopsis spp. (tickseeds), Solidago spp. (goldenrods), Agalinis spp. (false foxgloves), and Eupatorium spp. (thoroughworts) (Allen et al. 2001, Grace et al. 2000, LNHP 1986-2004). Many plants in Coastal Prairie also occur in the pine savannahs and flatwoods that occur immediately north of the coastal prairie region. These include many of the above, plus Drosera brevifolia (sundew), Polygala spp. (milkworts), Aletris spp. (colic-roots), Rhexia spp. (meadow beauties), and Sabatia spp. (rose-gentians). As mentioned previously, fire plays a critical role in this natural community. Certain woody species may invade this habitat without periodic fire. The introduced species Triadica sebifera (=Sapium sebiferum; Chinese tallow tree) has become especially problematic, forming dense thickets or forests. The transition zone from coastal prairie to pine savannah is extremely diverse with the two habitat types sharing most herbaceous species in the transitional area. Baygalls or bayhead swamps may be included within coastal prairie.

In addition to plants, coastal prairie and its adjacent marsh habitat provide immense spaces for waterfowl and thousands of other forms of wildlife. Waterfowl, sandpipers, and other shorebirds are abundant during the fall, winter, and spring months, paralleling and often surpassing other regions with longstanding traditions as crucial stopover areas for these species. Many rare European species, such as northern wheatear, black-tailed godwit, curlew sandpiper, and ruff, have also been routinely observed.

The coastal prairie is also home to the federally endangered Attwater’s prairie chicken (North America’s most endangered bird), and is the exclusive wintering ground of the federally-endangered whooping crane. Other residents such as the gulf coast hognosed skunk and the Cagle’s map turtle are also critically imperiled. A number of rare migratory grassland birds depend on coastal grasslands, including: the loggerhead shrike and Bachman’s, Henslow’s, and Texas olive sparrows.

Project Goals

To restore degraded Cajun Prairie to the project site and thereby expand the remaining area of this critically endangered ecosystem.

Monitoring

The project does not have a monitoring plan.

Description of Project Activities:
In February 1993, the title to a 334-acre FmHa easement tract was transferred to the U.S Fish and Wildlife Service. This tract is located in Evangeline Parish between Eunice and Mamou, Louisiana. The site was an abandoned agricultural area that was covered with thousands of Chinese Tallow Trees (Sapium sebiferum). The Tallow Trees were uprooted with bull dozers, wind rowed, and burned. The area was then disked and the levees removed. In January 1995, volunteers and Lacassine Wildlife personnel transplanted several truck loads of Cajun Prairie plants onto the site. The Cajun Prairie plants were obtained from a nearby remnant strip. A centrally located 90-acre portion of the tract was redisked in the spring of 1995. Using an airplane, seeds were sown on the 90 acres on May 2 and 9. The seeds included 270 lbs of Eastern Gamma Grass (Tripsacum dactyloides), 61 lbs of Aldous Little Bluestem (Schizachyrium scoparium), 171 lbs of Kaw Big Bluestem (Andropogon gerardii), 109 lbs of Cheyenne Indiangrass (Sorghastrum nutans), and 54 lbs of Alamo Switchgrass (Panicum virgatum). Seeds were again collected from remnants and sown into parts of the 90-acre plot in January 1996. In August 1998, seeds that were harvested from Attwater Prairie Chicken NWR in Texas were spread across the remaining acreage (244 acres). Also, in 1998 an experiment was begun to test the best time of year to plant seeds. Seeds were harvested from remnants and divided into four equal lots; one lot was planted in December 1998, two in February 1999, and one May 1999, with the two lots planted in February sown at two different sites. The results indicate that December was slightly better than February, and both December and February were much better than May. In the dormant seasons of 1998-99, 1999-2000, and 2000-2001, transplants were dug from remnants and transplanted into the Duralde prairie. In November 2000, seeds of 50 selected Cajun Prairie forbs were planted in monocultural plots. These seeds came from different remnants and are being planted together to test for increased seed production.

Ecological Outcomes Achieved

Eliminate existing threats to the ecosystem:
Areas that were subject to transplanting are close to being 100% restored back to Cajun Prairie. The seeded areas, on the other hand, are taking much longer, and it appears that they could require as long as ten years to become fully restored. More than 100 species of native Cajun Prairie plants now call this site home, and a number of native grasses have become well established. In the 90-acre tract, the dominant grasses are eastern gamma and switch grass, while in the 244-acre tract, the dominant grass is little bluestem. The occurrence of other grasses is low, but small clumps can be found scattered across the entire refuge. Some of the more conspicuous forbs that have become established include several species of button snakeroot (Eryngium yuccifolium), hairy sunflower (Helianthus mollis), and sweet goldenrod (Solidago odora).

Socio-Economic & Community Outcomes Achieved

Key Lessons Learned

The Duralde Cajun Prairie Project is the only Cajun Prairie restoration currently being undertaken on federally-owned land. It is hoped that these 334 acres will serve as a refugium for Cajun Prairie plants and animals and that they will mitigate the consequences of any further destruction of the remaining remnant strips.

Long-Term Management

Tallow trees (Sapium sebiferum) are the major concern for the long-term success of the project. The principal means of controlling this pest on the restored areas has been the use of approved herbicides. Very few tallows can be seen across the 334-acre tract, and it appears as though this pest has been kept under control for the moment. However, all project participants recognize that it continues to be a problem, and a constant vigil is maintained to prevent its recolonization.

Besides efforts to curtain the spread of tallow trees, management strategies also include controlled burning. The Duralde Cajun Prairie site has been treated annually with controlled burns since the inception of the restoration.

Sources and Amounts of Funding

Funding for the Duralde Prairie Restoration Project has been provided through grants from the U.S. Fish & Wildlife Service.

Other Resources

Coastal Prairie Ecosystem Description
http://www.tarleton.edu/~range/Grasslands/Tallgrass%20Prairie%20(Coastal)/tallgrassprairieCostal.html

Cajun Prairie Habitat Preservation Society
http://www.cajunprairie.org/

Primary Contact

Organizational Contact