Reproduction in established stands of Pacific cordgrass is vegetative 

 through extensive underground stems (rhizomes). Although seed production is 

 erratic and usually limited in old, dense stands, it may be substantial in 

 newly established stands or along the margins of older stands. Seeds are 

 important for spreading the plant into new or freshly disturbed areas (Mason, 

 1976). 



The capacity of Pacific cordgrass to grow lower in the tidal zone than any 

 other marsh species on the Pacific coast makes it especially valuable for 

 shore stabilization. 



a. Planting Techniques. 



(1) Sprigs . Sprigs are the least expensive plant material and are 

 the easiest to plant. A sprig consists of at least one node (joint of a stem 

 from which leaves arise) with attached stems and roots. Sprigs are obtained 

 from existing marshes. Field nurseries can be established as a source of 

 plant materials, an early Pacific coast planting (Knutson, 1976) is now in use 

 as a field nursery. In sandy substrates individual clumps may be loosened 

 with a shovel, lifted, and separated into individual sprigs; however, the task 

 is very laborious and likely to produce poor-quality plants in fine-grained 

 sediments. In this case, plugs must be dug from the marsh and the individual 

 sprigs separated with the use of a knife or other implement. In sandy sedi- 

 ments the highest quality transplants can be obtained from uncrowded stands 

 which do not have a dense root mat. However, areas where Pacific cordgrass 

 can be harvested on sandy sediments are rare. Because the natural spread of 

 Pacific cordgrass is relatively slow, no more than 10 percent of the harvest 

 area should be disturbed. Transplants may be hand-planted by inserting them 

 10 to 15 centimeters deep in holes opened by a dibble or shovel. In saturated 

 fine-grained sediments the transplants may often be inserted without the use 

 of implements. The soil around plants should be firmed to prevent "float 

 out." Planting is generally feasible only during low water when the substrate 

 surface is exposed. 



(2) Pot-Grown Nursery Seedlings . Nursery seedlings are plants grown 

 from seed in peat moss or plastic pots under controlled conditions. Three- to 

 four-month-old seedlings are an alternative to sprigs. Five- to seven-month- 

 old seedlings may be preferable to sprigs particularly if transplanted late in 

 the growing season. Pot-grown seedlings are relatively easy to produce but 

 considerably more expensive than sprigs (Fig. 25). 



To prepare seedlings, seeds must be harvested from existing stands of 

 Pacific cordgrass (Fig. 26). Seed production in Pacific cordgrass is very 

 erratic. Early investigators believed that viable seeds were seldom produced 

 and of minor significance in the spread of this species (Purer, 1942; Hinde, 

 1954). However, substantial seed crops (viability 80 percent) have been found 

 in the San Francisco Bay area. Seeds from these sites have been harvested and 

 stored, and plants have been produced from them (Mason, 1976). The best seed 

 production was located near tributaries to the bay. The lower salinities at 

 these sites may be a factor encouraging seed formation although this has not 

 been established. Like smooth cordgrass, Pacific cordgrass seed heads may be 

 attacked by ergot. 



58 



