3. Comparison of Seeds, Sprigs, and Plugs . 



A comparison of the success of using seeds, sprigs, and plugs to 

 establish a marsh was made at San Mateo and Alameda Creek (area 1). The 

 San Mateo site is located on the western shore of San Francisco Bay and 

 is not exposed to prevailing winds. The site faces fetches from 14 to 

 21 kilometers, but winds blow onshore only about 14 percent of the time 

 at an average speed of 8.5 kilometers per hour. The Alameda Creek (area 

 1) site is exposed to the prevailing westerly winds. Winds blow onshore 

 at this site about 47 percent of the time at an average speed of 17.5 

 kilometers per hour. Area 1 is also exposed to broader fetch ranges 

 from 11 to 35 kilometers. 



A 150- by 15-meter area of the San Mateo site was hydroseeded (seed 

 in water applied by hose from a tank truck) with 150 liters of seed. 

 Inspection of the site immediately after seeding indicated that the 

 process had torn the seed embryos from their hulls. Two days later, the 

 only evidence of seeding was the presence of a drift line of seed debris. 

 Parts of the hydroseeded area were hand-raked and additional areas were 

 hand-seeded and raked. No seed germination was observed using either of 

 these techniques. Hand-seeding attempts at the Alameda Creek (area 1) 

 were also unsuccessful, due probably to exposure to wave action (Table 2) 



Sprigs and plugs were planted in front of, and extending up, a 0.2- 

 meter bank at San Mateo in July 1976. One month after planting, only 

 54 percent of the plugs and 6 percent of the sprigs survived. Greatest 

 mortality occurred on, or immediately beneath, the bank. Five months 

 after planting, no plants were alive. 



Sprigs and plugs were planted at the Alameda Creek (area 1) site in 

 May 1976. At some locations of this site there were banks 0.3 meter 

 high. In August, 3 months after planting, only 30 percent of the plugs 

 and 5 percent of the sprigs were alive. Five months after planting, 

 plug and sprig survivals were 13 and 2 percent, respectively Eight 

 months after planting, there were no live plants, reflecting high ex- 

 posure to waves. 



Seed, sprigs, and plugs were not successful in establishing vegeta- 

 tion on the two exposed sites tested. Seeding offers little promise 

 whereas, plugs appear to be more tolerant to wave action than sprigs. 



Having determined that plugs are more tolerant to wave action than 

 seeds or sprigs, the 1977 planting focused on improving establishment 

 techniques for plugs. 



4. Plugs with Wave Breakers . 



As discussed previously, plugs with and without individual shingle- 

 type wave breakers were planted in replicate plots at the Alameda Creek 

 (area 2), San Mateo, and Point Pinole sites. Figure 10 and Table 4 

 summarize survival and growth of the plugs with and without shingles. 



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