A few workers have examined the early stages of maturation in 

 planted stands (Garbisch, Woller, and McCallum, 1975; Camraen, 1976; 

 Cammen, Seneca, and Copeland, 1976; Newcombe and Pride, 1976; Morris 

 and Newcombe, 1978). This is not a rapid process and it is one that 

 may vary a great deal with such things as location, size of planting, 

 substrate, salinity, and tidal regime. 



In any event, once a stand is established, it seems highly unlikely 

 that mode of initiation of the marsh will affect the rate of marsh 

 development. 



5. Cost . 



The labor required to acquire or produce propagules and to plant 

 is the principal cost of marsh building after site preparation. Labor 

 demands vary widely with species, availability of plants and seeds, 

 type of propagule, accessibility of the site, substrate type, size of 

 operation, and degree of mechanization used. 



The most extensive experience is with sprigs (intact single-stem 

 plants) of smooth cordgrass. Estimates for digging, processing, and 

 planting range from about 75 hills per man-hour for a manual operation 

 (Dodd and Webb, 1975) to about 200 hills per man-hour where digging 

 and planting are mechanized (Woodhouse, Seneca and Broome, 1974). 

 Dodd and Webb (1975) worked with a variety of species and found that 

 the more difficult plants, giant reed and American bulrush, required 

 about 1 man-hour per 35 hills. 



Knutson (1977a and 1977b) summarizes propagule and planting labor 

 requirements for four cordgrasses, (smooth, saltmeadow, gulf, and 

 Pacific) as follows: 



Sprigs: 1 man-hour per 100 hills 



Peat-pot seedlings: 1 man-hour per 20 hills 



Plugs: 1 man-hour per 10 hills 



Seeds: About 25 percent as much time as sprigs 



Ternyik (1977) , using an untrained crew, found the production rate 

 of sedge (three-culm) and tufted hair grass (seven-culm) sprigs to be 

 similar to that reported for th.e cordgrasses. He felt that this could 

 be substantially ijiproved with ejcperiejice. 



Working hours in the intertidal zone are controlled by tidal re- 

 gimes. Both harvesting and planting are usually confined to about a 

 5-hour period per tide. This restriction requires careful coordination 

 for efficient operation and often adds substantially to the cost. 



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