establishing vegetative cover in the intertidal zone. Stabilization can be 

 accomplished rapidly and at low cost by planting smooth cordgrass. This will 

 be followed on most sites by the natural invasion and eventual takover of 

 mangroves, if there is an adequate seed supply. Planting of mangrove seed, 

 seedlings, or plants in the cordgrass stand soon after stabilization would 

 speed the transition, if desired. 



a. Planting Techniques . Plants should be set in holes large enough to 

 accommodate the root mass, at about the same level in the ground as they were 

 growing, with the edges of the hole filled and firmed. This can be done best 

 at low tide. The root ball should be kept intact and care taken not to cover 

 pneumataphores or prop roots. 



Watering is advisable at higher elevations where daily flooding does not 

 occur. Pruning definitely improves survival and early growth. Black and 

 white mangroves should have top and side branches pruned to about two-thirds 

 of their original length. Pruning of red mangroves must be selective; lateral 

 buds may not grow on branches pruned back to a diameter greater than 2.5 

 centimeters (Pulver, 1976). 



b. Salinity . Tolerant to sea strength 35 parts per thousand. 



c. Planting Zone . Established red mangroves tolerate continuous water 

 coverage of the substrate surface 0.5 meter deep to occasional flooding a few 

 centimeters deep. The black mangrove grows slightly higher, under a few 

 centimeters of standing water to barely flooded by spring tides or storm 

 surges. The white mangrove will grow with the other two at about all eleva- 

 tions (Davis, 1940). Successful plantings of all three species have generally 

 been above MTL. Propagules and young plants cannot tolerate continuous flood- 

 ing (Teas, 1977). It may be possible to succeed at lower elevations by using 

 older plants. 



d. Planting Density . Seedlings may be planted as close as 0.5 meter on 

 centers and natural thinning permitted to determine the final stand. With the 

 more expensive saplings, a 2- to 3-meter spacing is suggested. 



e. Planting Width. No minimum. 



f . Planting Date . The optimum planting season of young seedlings , dug 

 from the wild, is in late February and March. Planting of larger plants can 

 probably be done successfully throughout the year if done with care. 



g. Fertilization Requirements. There are no data to support the use of 

 fertilizers on mangrove planting. These species respond to fertilizer in 

 nurseries (Teas, 1977) and will probably respond to the addition of nitrogen 

 and phosphorus in the field on some sites. The cost of slow-release materials 

 such as osmocote or mag-amp applied in the planting hole, would be warranted 

 if needed, for the larger transplants. Fertilization should be tried wherever 

 nutrient limitations are suspected. 



h. Planting Management . Smothering by drifting debris is a problem on 

 some sites, particularly with small plants. Removal of debris should be prac- 

 ticed during the period of establishment. Pruning of established plants may 

 be continued where mangroves play an ornamental role. The black and white 



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