The amount of fetch that may be tolerated by marsh plantings 

 varies with the alinement of the site in relationship to the direc- 

 tion of the strong winds, wind velocities, and the seasonal timing 

 of the winds as well as nearshore topography, tidal currents, 

 species, and type of substrate. In general, sites open to fetches 

 in excess of 4 or 5 kilometers should not be planted with sprigs or 

 plugs, and unprotected sites exposed to fetches over 1 kilometer 

 should not be seeded. 



III. MARSH SOILS 



1. Types. 



Coastal marshes grow on a wide variety of substrates, on mineral 

 soils from coarse sands to fine clays, and peats and mucks of varying 

 organic matter content and degree of decomposition. Marsh growth 

 and productivity is favored by high mineral content of the substrate 

 (DeLaune, Buresh, and Patrick, in preparation, 1979). At least a 

 part of this effect appears to be due to the higher concentration of 

 nutrients in most mineral soils. The predominantly organic soils 

 may contain equal amounts of nutrients on a dry weight, but much less 

 on a volume basis. Sands are usually much lower in nutrients than 

 are silts and clays (Woodhouse, Seneca, and Broome, 1974; Garbisch, 

 Woller, and McCallum, 1975). 



Planting is easiest on sandy soils. These are more likely to 

 have adequate bearing strength and provide sufficient traction for 

 machine planting. The opening and closing of planting holes or 

 furrows is also easier in sandy substrates. The principal disadvan- 

 tage of this type of soil is the low nutrient content. This may not 

 constitute a serious handicap in nutrient-rich waters but becomes 

 acute enough, in some cases, to require the use of fertilizers to 

 assure rapid establishment. 



Silts and clays usually contain ample nutrients for normal growth 

 of marsh species and usually support the most productive marshes. 

 They are not, however, always easy to plant. Some are too soft for 

 machinery and others are too stiff for the opening and closing of 

 planting holes. Planting holes may have to be opened with an auger 

 in some compact silts and clays and float-out of fresh transplants is 

 more common with these soils. Planting in extremely soft materials 

 can cause problems in the approach to planting and in keeping plants 

 or seeds in place until they can securely anchor themselves. Exces- 

 sive softness is common in recently deposited, fine-grained dredged 

 materials. Overly compacted soils are more common along eroding 

 shorelines. 



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