Paspalum vaginatum , seashore paspalum (Figure 8), is a perennial plant with culms 

 10 to 60 cm tall arising from an extensive system of long, slender rhizomes in coastal 

 sands. Its distribution is from North Carolina to Florida and Texas, south to Argentina, 

 and also in the Old World tropics. Paspalum flowers between late summer and winter. 



In Louisiana, seashore paspalum, occupies environments similar to seashore 

 dropseed, i.e., sand flats and embryo dunes. Both species can also be found in sandy, 

 wetter interdunal areas protected from salt spray effects. Although this species is not a 

 dominant dune plant in Louisiana, its fibrous root system makes it a prime candidate for 

 dune stabilization trials. 



Seashore paspalum is a low, creeping grass, resembling coastal bermuda grass, 

 (Cynodon dactyl on ), that spreads by runners as well as rhizomes. The flowering culms of 

 this plant are usually less that 0.3 m high. Although seashore paspalum can endure on 

 very wet sites, even salt water inundated, this plant also builds small hummock dunes on 

 dry flats. 



Seashore paspalum can easily be propagated by transplanting runners or rhizomes. 

 Optimum planting time and depth are similar to seashore dropseed. Transplants should 

 be 46 cm apart. 



Uniola paniculate , sea oats (Figure 9), is a perennial plant with 1.2 to 2 m tall stout 

 culms arising singly or in small clusters from long, thick rhizomes. This species is found 

 on dunes and sandy flats along the ocean from Virginia to Texas, northern West Indies, 

 and eastern Mexico. Sea oats flowers from June to December, but mostly in late summer 

 and early autumn. 



Although sea oats is the most important and widespread grass on coastal dunes in 

 the Southeast United States (Craig 1976), its importance in Louisiana is limited. Sea oats 

 is found on Louisiana's Chandeleur islands, but with the exception of a few small isolated 

 populations, is almost completely lacking on the barrier islands and beaches west of the 

 Mississippi River Delta. The dominance of sea oats is not reestablished until the area of 

 Padre Island, Texas. The reason for this disjunction is unclear, although factors such as 

 the lack of a large seed source, impact of frequent washover events due to hurricanes, 

 and dune formations which are too low in elevation to prevent plant roots from entering 

 the water table are possible causes. 



Although sea oats produces viable seeds, which are important in colonizing new 

 areas (Woodhouse et al. 1968), the plant spreads primarily from long extended rhizomes. 

 Sea oats leaves are narrow, pale green, and die back in the winter in more northerly 

 latitudes. The leaves are normally rolled inward. The stems of this plant are slender and 

 up to I m tall. The seed heads are compressed spikelets borne at the end of stiff culms. 

 Seeds mature in the fall. 



Seed germination is not high, and seedling survival is low (Seneca 1969; Graetz 

 1973). Thus propagation via transplants will provide the highest success. In Louisiana, 

 sea oats cannot be thinned from existing populations since these populations are already 

 too small. Sea oats transplants can be obtained, however, from commercial supply 

 houses for dune stabilization measures in Louisiana. When replanting, the transplants are 

 set at least 0.3 m deep and packed in tightly. The basal part of the leaves may be buried, 

 but deep planting is desired to keep the roots moist. 



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