Apply 1 to 3 kilonewtons of nitrogen (N) and 1 kilonewton of phosphate 

 (P20c) per hectare from soluble sources (anmonium sulfate and concentrated 

 superphosphate, or dianmonium phosphate) or in slow-release materials such as 

 osmocote or mag-amp (see Sec. V for details on fertilization requirements). 



h. Planting Maintenance . litter such as wood, styrofoam, algae, and 

 dislodged plants accumulate and form a debris line. This material may smother 

 and damage plantings particularly during the first two growing seasons. The 

 litter should be removed in both the fall and the spring. Areas within the 

 planting that are damaged by storms should be replanted. 



i. Summary . 



(1) Plant types - sprigs, pot-grown seedlings, or plugs. 



(2) Plant spacing - 0.5 meter (40,000 propagules per hectare). 



(3) Minimum planting width - no minimum width on sheltered sites; 

 for exposed sites 6.0 meters or 60 percent of the upper one-half of 

 the intertidal zone, whichever is larger. 



(4) Salinity range - less than 35 parts per thousand. 



(5) Planting zone - MTL to mean lower high water (MLHW) . 



(6) Optimal planting date - April. 



(7) Fertilization - 1 to 3 kilonewtons of nitrogen (N) and 1 

 kilonewton of phosphate (PoOc) per hectare. 



3. Pacific Northwest . 



Few of the relatively large variety of plants found in marshes along this 

 coast presently offer promise for planting purposes. More will probably be 

 found useful with further experience. There is no single species such as 

 Pacific cordgrass on the south Pacific and smooth cordgrass on the Atlantic 

 and gulf coasts colonizing and dominating the lowermost, regularly flooded 

 zone of salt marsh vegetation in this region. Jefferson (1975) identifies 

 four species — Lyngbye's sedge, seaside arrowgrass, pickleweed, and tufted 

 hairgrass — as the most important in trapping sediments along the Oregon 

 coast. Of these four species, Lyngbye's sedge appears to be the most 

 promising plant for use in erosion control. 



a. Lyngbye's Sedge (Cavex lyngbyei) . This plant is a major component of 

 salt, brackish and fresh water marshes in the northern Pacific coast (Fig. 

 28) . The species composition of these northern marshes is more diverse than 

 that found in other coastal areas of the United States. Also, less discrete 

 elevation zones of vegetation are found in the less saline marshes of the 

 northern Pacific, with a gradual change southward to the southern Pacific 

 coast section between Humboldt Bay and San Francisco (Mac Donald and Barbour, 

 1974). Little guidance is available for planting in the northern region. 

 Successful intertidal plantings have been made in the Columbia Eiver estuary 



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