site preparation. The elevation was de- 

 termined by the U.S. Geological Survey 

 prior to site preparation. A level line 

 from a U.S. Coast and Geodetic primary 

 tidal bench mark in Darien, Georgia, was 

 extended to the site. A temporary bench 

 mark, established on high ground of ad- 

 jacent Little St. Simons Island, was 

 used to determine the elevation of the 

 site. Subsequently, a tidal gage was in- 

 stalled so that simultaneous comparisons 

 could be made between the study area and 

 the primary National Ocean Survey tide 

 stations at Fort Pulaski, Georgia, and 

 Mayport, Florida. 



METHODS 



Often it may be necessary to sup- 

 plement the nutrient content of soils 

 with commercial fertilizer applications 

 so that marsh plants can become success- 

 fully established. Marsh plant-soil in- 

 teractions were evaluated in terms of 

 carbon, nitrogen, and phosphorus levels 

 to gain information about nutrient up- 

 take by marsh plants and to determine 

 marsh plant response to fertilizer ap- 

 pl ication. 



The site was graded so that an ele- 

 vation gradient was established from 

 mean high water level to mean low water 

 over a seaward distance of 60 m (200 

 ft), and 150 m (490 ft) horizontally. 

 Within this intertidal area a series of 

 research plots, each 1.5 by 3 m (5 by 10 

 ft), were established with a 0.7-m (2.3- 

 ft) border between each plot. 



The variables included in the fac- 

 torial design were (1) elevation: low 

 (lower third of intertidal zone), middle 

 (middle third of intertidal zone), and 

 high (upper third of intertidal zone); 



(2) vegetation propagules: no propagule 

 introduced except as naturally might oc- 

 cur, or one of the following seven plant 

 species: Borrichia frutescens , Distich- 

 1 is spicata , Iva frutescens , Juncus roe- 

 merianus , Spartina a! terniflora, Spar- 

 tina cynosuroides , and Spartina patens . 

 These plants were all common inhabitats 

 of natural marshes near the study area; 



(3) fertilizer treatment: no fertilizer, 

 low level of inorganic fertilizer (122g/ 

 m?), high level inorganic (244 g/m^), 

 low level organic (33 g/m2), high level 



organic (66 g/m2).The inorganic fertil- 

 izer was manufactured by Kaiser Agricul- 

 tural Chemicals under the trade name of 

 "Bounty". The analysis of the inor- 

 ganic fertilizer was 10% nitrogen, 10% 

 phosphorus, and 10% potash. The nitrogen 

 components of that fertilizer included 

 3% nitrate-nitrogen from ammonium ni- 

 trate and 7% ammoniacal nitrate. The 

 organic fertilizer manufactured by Kerr- 

 McGee Corporation and sold under the 

 name of "Gro-tone" had an analysis of 

 16% nitrogen, 4% phosphorus, and 8% pot- 

 ash with organic sources of nitrogen in 

 the formulation; (4) types of propa- 

 gules: sprigs and seeds. The sprigs 

 were transplanted during June 1975 from 

 marshes adjacent to the research plot. 

 The seeds were collected from seed-pro- 

 ducing plants adjacent to the research 

 plot during the summer, fall, and winter 

 of 1975 and were planted in April 1976 

 after appropriate winter cold treatment. 

 Propagules were planted on 0.5-m (1.6- 

 ft) centers in each of the test plots. 

 Each of the above factors was randomized 

 with three replicates. Consequently, 

 there were a total of 720 test plots in 

 the research area. 



Several parameters were measured to 

 follow the success of the developing 

 marsh. Analysis of the soil included 

 mineral nutrients and physical analysis. 

 The test plots were observed for the 

 presence and abundance of macroinverte- 

 brates and vertebrates. Fiddler crabs, 

 snails, and other wildlife use of the 

 area were observed and recorded begin- 

 ning with the initiation of the project. 

 The chemical analysis of the surrounding 

 waters, as well as the interstitial wa- 

 ter in the plots, was conducted through- 

 out the project (Figures 2 and 3). 

 Amounts of nitrogen and phosphorus in 

 the water column appear to follow the 

 typical estuarine pattern of high con- 

 centrations in winter and low concentra- 

 tions in summer. There has been no evi- 

 dence of eutrophication from the fertil- 

 izer added to the test plots. 



An analysis of the plants and their 

 success in establishment was made. The 

 remainder of the paper deals specifical- 

 ly with the resultant plant growth of 

 the sprigs transplanted June 1975 as an 

 indicator of the success of the estab- 

 lishment of the salt marsh. 



12 



