density varied from 148 per meter squared in the densest area to 58 

 stems per meter squared in the sparsest area. The survival and repro- 

 duction apparently reflected protection provided by artificially placed 

 rocks and shell. Smooth cordgrass clumps planted by refuge personnel 

 in the past have survived in other areas with rock and shell cover 

 (R. Clapper, personal communication, 1974) . 



Blocks XVII and XVIII, protected with one tier of tires, were 

 planted in July 1975. Shortly after planting the barrier sank and was 

 ineffective. Only one small clump of smooth cordgrass remained in each 

 block in June 1976. 



Block XI was originally protected in March 1975 with a wave-stilling 

 device constructed of wire and hay bales; survival was only 8.9 percent 

 in the protected areas (Webb and Dodd, 1976) . Using the number of 

 surviving transplants in October 1975 as a measure of survival, a range 

 of 11 to 215 stems per surviving plant occurred in August 1976. By 23 

 June 1977 the number of stems had approximately tripled. The number of 

 stems exceeded 1,000 per plot in several plots (Table 7, Fig. 8). It is 

 possible that the hay deposited in the soil, or that the remaining fence 

 modified soil parameters and wave action to allow growth and reproduction. 



V. SUMMARY AND CONCLUSIONS 



Survival and tiller production of smooth cordgrass occurred within 

 the tidal zone behind a wave-stilling device constructed of two tiers of 

 tires strung on a cable. Gulf cordgrass, marshhay cordgrass, and salt- 

 grass survived at elevations above ^'IHW. 



Differences in survival and reproduction between fenced and unfenced 

 areas indicated that rabbits were a problem. At elevations above MHW 

 smooth cordgrass was not able to survive and produce tillers in suf- 

 ficient numbers to stabilize the shoreline. Tillering increased with both 

 depth and hours of inundation. No plants were subjected to more than 14 

 hours of inundation. The greatest tillering of smooth cordgrass occurred 

 in the freshly deposited silt near the tire barrier. 



Height of smooth cordgrass plants was greatest at the lowest eleva- 

 tions and decreased with increasing elevation. The plants were over 100 

 centimeters tall where inundation was frequent, but less than 25 centi- 

 meters where inundation was infrequent. 



Survival of needlegrass rush was low. Marshhay cordgrass, gulf 

 cordgrass, and saltgrass exhibited an 80 percent or better survival at 

 the lowest planted elevations (approximately 0.46 meter). Inundation 

 was less than 2 hours daily. At the highest planted elevations survival 

 did not exceed 50 percent, regardless of species. Inundation was infre- 

 quent with a mean of 0.3 hour daily at the highest elevations. Seed 

 heads were produced on gulf cordgrass and marshhay cordgrass in fall 

 1976 and in June 1977. 



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