Transplant Canister and Aerial Seeding Applications of Spartina Alterniflora for Large-Scale Coastal Marsh Restoration.

Louisiana coastal marshes suffer from a catastrophic land loss of 40 square miles annually.  Constructions of new wetlands, terraces, and barrier islands or modification of hydrology through river diversions are current efforts to slow down the land loss and could serve as a foundation of future coastal wetland systems.  Economical and rapid revegatation techniques are needed to stabilize these areas.  The objectives of this study were to evaluate the potential applications of transplant canisters and aerial seeding of smooth cordgrass (S. alteniflora).

            Seed of smooth cordgrass was produced from a cultivated polycross population of 15 seed producing lines (PolyC15) grown at the Rice Resesearch Station near Crowley, LA. The seeding was conducted using a commercial aerial application plane on March 31, 2010.  The seed used in the aerial study was harvested in mid November of 2009.  Prior to loading onto the airplane, PolyC15 seed was mixed with clay absorbent as a spreader.  A total of 60 lbs of cleaned seed were used.  The average germination rate of PolyC15 seed was 70%.  The plane was calibrated by adjusting a hopper opening at a given air speed to deliver seed in the rate of 10, 20, and 30 lbs/A. Each seeded area was a 40 x 1,000 foot strip separated by a 56 ft unplanted area.  Aerial application led to an average density of 10, 22, and 32 viable seeds/ft²  corresponding very closely to  seeding rates of 10, 20, and 30 lbs/A. While aerial seeding is suitable for low energy areas, transplant canister is targeted for high energy areas. Research findings from aerial seeding at Bayou Dupont – Belle Chase, simulated aerial seeding at Rockefeller site, and applications of transplant canister will be presented and discussed.