Germination tests were made to determine an optiiim planting period. 

 At 2-week intervals, seed samples were removed from storage and placed 

 in freshwater. The precentage of seeds that germinated was recorded. 

 Seed samples were also placed in solutions of 0, 10, 20, and 30 parts per 

 thousand salinity to determine the best solution for germination. 



(2) Field Planting . Both hand and mechanical seeding was done. 

 The application rate for seeding was approximately 100 seeds per square 

 meter. Hand-sown seeds were raked into the substrate and covered with 

 a thin layer of mud to prevent them from floating. Mechanical planting 

 was performed with a hydromulch machine with a nozzle pressure of about 

 10 kilograms per square centimeter. 



b. Sprigs . A sprig is a single stem (culm) with associated root 

 and rhizomal material. Clumps of cordgrass were collected in existing 

 natural marshes and separated into individual sprigs. Only culms with- 

 out inflorescenses, ranging in size from 7 centimeters tall in the spring 

 to 25 centimeters tall in the fall, were used. The sprigs were hand- 

 planted to a depth of 7 to 10 centimeters, depending on the sprig size. 



A hole was pressed into the substrate, the sprig was placed in the hole, 

 and then the mud was compressed around the sprig. 



c. Plugs. A plug is a group of stems with attached root and rhi- 

 zome material which is collected and planted with the sediment mass 

 intact. Tests were conducted -on two types of plugs: (a) plugs protected 

 by construction shingles inserted in the mud to act as wave breakers; and 

 (b) bioconstructs with ribbed mussels (Isahadium demissvm, formerly 

 Volsetta dem-issus) imbedded in the rhizome mass. 



(1) Plugs With and Without Wave Breakers . Plugs, 15 centimeters 

 square and up to 10 centimeters tall, were collected from dense cordgrass 

 stands. The plugs were selectively dug to obtain a maximum number of 

 culms per unit of surface area. Holes were dug into the mud with a square- 

 tipped spade, deep enough for the planted plugs to be flush with the mud 

 surface. The plugs were then pressed into the holes by hand. To pro- 

 tect each plant, construction shingles, measuring 15 to 25 centimeters 

 wide and 30 centimeters long, were pressed 20 centimeters into the sub- 

 strate. For very small plugs, two shingles were placed in a "V" for- 

 mation in front of the plant with the apex facing the wave fronts. 



Larger plugs were protected by arranging three or four shingles in a 

 staggered pattern across the exposed side of the plant. 



(2) Cordgrass Mussel Bioconstructs . Cordgrass plugs with ribbed 

 mussels were obtained from a stand fully exposed to bay wave activity, 

 located approximately 1.5 kilometers north of Alameda Creek. The bio- 

 constructs measured approximately 25 centimeters square and up to 15 

 centimeters tall. Although the cordgrass was stunted in height, as was 

 typical in stands exposed to strong wave action, it was healthy in terms 

 of density of shoot growth and the lack of noticeable necrosis. The 

 planting procedure was the same as for the plugs without ribbed mussels 

 with three additional steps. The substrate surface was manually 



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