the 5-centimeter pots about 3 months before transplanting or 4 to 5 months 

 before transplanting If 10-centlmeter pots are used. Plastic containers are 

 usually preferable to avoid intertwining of roots between pots. It is 

 advisable to apply enough seed to provide 6 to 10 viable seeds per pot, but 

 seedlings should be thinned to 2 to 4 per pot to avoid overcrowding. Excess 

 seedlings may be transplanted to other pots. The pots should be irrigated 

 with tapwater and fertilized after the seedlings emerge with 10-10-10 

 fertilizer, or a slow-release material may be mixed in the pot. If the 

 seedlings are to be transplanted in site salinities above 15 parts per 

 thousand, the solution should be adjusted with sodium chloride to maintain a 

 salinity comparable to the site (Garbisch, 1977a; E Garbisch, Environmental 

 Concern, Inc., personal communication, 1977). 



Plastic pots should be discarded before planting and peat pots should be 

 scored to encourage extension of the roots beyond the confines of the pot. 

 Seedlings should be planted in holes opened with a shovel, spade, dibble, or 

 auger. They can be planted by machine using a suitably equipped planter. 

 Pots should be set slightly below the substrate surface and soil firmed 

 tightly around them. 



(3) Plugs . A plug is a root-soil mass, 10 to 15 centimeters in 

 diameter and 15 to 20 centimeters deep, which contains roots and a number of 

 stems. Plugs can be used as an alternative to the 5- to 7-month seedlings for 

 late plantings, or as an alternative to sprigs where plants must be obtained 

 from old, dense materials. 



Plugs are harvested from existing marshes which have heavy-textured 

 sediments. An intact root-soil mass cannot be maintained if plugs are 

 excavated from noncohesive, sandy sediments. Culm size and vigor is important 

 for plugs just as it is for sprigs and for the same reasons. One to three 

 large culms per plug are always preferable to a larger number of smaller culms 

 in the same size plug. Similar to potted seedlings, plugs should be planted 

 slightly below the substrate surface and soil firmed tightly around them. 



b. Soils and Salinity. Cordgrass is well adapted to sea-strength 

 salinity (35 parts per thousand and also to the anaerobic substrates charac- 

 teristic of most salt marshes. Its oxygen transport system consists of 

 hollow, air-filled tissue, extending from openings in the leaves to the roots 

 and rhizomes (Teal and Kanwisher, 1966; Anderson, 1974). Thus, oxygen reaches 

 the below-ground tissues in anaerobic substrates. Cordgrass will grow in a 

 wide range of substrates from coarse sands to silty clays to peats. Although 

 dominant in regularly flooded, saline habitats, it is not restricted to these 

 areas; it usually attains maximvon growth under lower salinities (10 to 20 

 parts per thousand) . The grass will grow and reproduce normally under 

 freshwater conditions but is subject to increasing competition from other 

 species as salinity declines (Woodhouse, Seneca, and Broome, 1974). 



c. Planting Zone . Smooth cordgrass usually grows from MHW to near mean 

 low water (MLW) in locations with narrow tidal ranges, and from MHW to MSL in 

 locations with broader tidal ranges (Woodhouse, Seneca, and Broome, 1974). 

 Table 2 is a summary of four observations of smooth cordgrass survival in 

 lower intertidal areas. In each of the above areas water level fluctuations 

 were principally a product of astronomical tides. In areas with pronounced 



53 



