transplantation, and (2) commercial 

 growers. The California Native Plant 

 Society, Berkeley, should be contacted for 



information on availability of seeds and 

 plants of native species. 



* In locating material to plant, it 

 is important to draw from local 

 genetic resources, so that natural 

 gene pools are not tampered with, and 

 so that populations with the required 

 degree of salt and drought tolerance 

 are obtained. Plants from central 

 and northern California have not been 

 compared to southern California 

 populations, so we are not certain 

 how different they are genetically. 

 However, the growing conditions are 

 much more favorable in areas like San 

 Francisco Bay, and genetic divergence 

 is likely. Transplants and seeds 

 should come from adjacent marshes 

 wherever possible, and certainly not 

 from outside the region. 



1. Hypersalinity of soils: Because 

 the usual condition of intertidal soils is 

 stressful, establishing plants is 

 difficult. 



Transplantation success will be 

 greatest if planting occurs during periods 

 of lower salinity or in places where 

 soils are under 50 to 60 ppt. Freshwater 

 irrigation during the early planting phase 

 would probably be helpful, but such 

 experiments have not been done. 



2. Grazers pose serious problems to 

 plantings on exposed soils. Several 

 species are probably responsible for the 

 damage to transplants, but small rodents 

 seem to be the major offenders. 



Protection of transplants from 

 herbivores is usually required. Fences 

 made of aviary wire (1/2-inch mesh) 

 eliminate grazing, while fences of chicken 

 wire (over 1-inch mesh) do not. 



• To reduce the amount of material 

 required for transplantation or 

 seeding, it is recommended that the 

 marsh establishment program take 

 place in phases. The initial 

 planting should be done to create an 

 on-site nursery for later plantings. 

 This will reduce expenditures as 

 well, because it will serve as a test 

 plot and determine the establishment 

 success before large areas are 

 planted. The most suitable habitat 

 should be selected for the nursery 

 site so that growth is maximized 

 (e.g. low salinity, protected from 

 wave force, proper elevation for 

 species to be transplanted). 

 Plantings at two-meter intervals 

 should allow easy harvesting of new 

 offshoots during the following 

 growing season. Planting in soils of 

 higher sand content will allow easier 

 collection. 



The following constraints for marsh 

 vegetation establishment have been 

 identified in experimental studies near 

 San Diego (Zedler 1981a). Where possible, 

 solutions to the problems are suggested. 



3. Competition with Salicornia 

 virginica can reduce growth and expansion 

 rates of Spartina foliosa (and probably 

 other halophytes as well), but plantings 

 done within established canopies 

 experience less grazing. If grazing is 

 likely to be a problem in the transplant 

 area, and if Salicornia virginica has 

 already invaded, it is advisable to leave 

 the competing vegetation. Transplants 

 will grow more slowly, but expensive 

 grazing exclosures will not be required. 



In designing the exact planting 

 scheme for marsh halophytes, elevation and 

 soil salinity are the most important 

 features . 



* For greatest success, species 

 should be planted at their elevation 

 of greatest natural abundance (as in 

 Figure 9) . 



* Soil salinities at these 

 elevations should not exceed those of 

 the natural habitat (see Figure 11) 

 for values at different times of the 

 year). Salinities lower than those 

 in Figure 11 would be preferable. 



97 



