preceding layer. This method has a high labor requirement, and it inter- 

 feres with subsequent planting. Use probably should be limited to small 

 blowout areas. 



Conventional mulches of straw, wood fiber, and Fiberglass are diffi- 

 cult to anchor to dune surfaces and require careful protection of edges 

 to prevent rollup by wind action. 



A cover of crushed stone or clay will provide immediate protection to 

 a dune surface and this is probably the most practical remedy, short of 

 paving, in traffic areas. It is expensive and usually can be confined 

 to small parts of the dune. Unless the surrounding areas are stabilized, 

 the material may become buried and lost. 



2. Asphalt, Latex, and Chemicals . 



Another method for rapid stabilization of sand is to apply binding 

 agents to the surface layer. Asphalt emulsion and latex compounds are 

 commonly used. Asphalt is often used to tack mulches to exposed sur- 

 faces. This is useful as a temporary stabilizer during the establish- 

 ment of vegetation. As with netting and mulches, the edges must be 

 protected from undermining, and the surface protected from traffic. 



Adriani and Terwindt (1974) tested sand binders when establishing 

 vegetation on the Europoort sand dikes. Three emulsions were tested. 

 Two had a bituminous base and the third a base of rubber. All three 

 emulsions were detrimental to the development of transplanted dune 

 grasses. They concluded that this method was of little value under 

 these conditions. 



Zak and Bredakis (1963) tested asphalt emulsion, asphalt cutback, and 

 elastomeric polymer emulsion in water, a polyvinyl polymer emulsion in 

 alcohol, and a solution of sodium silicone following an ammonium sulfate 

 and gelatin spray to stabilize the sand surface after sowing seeds at 

 Cape Cod. The asphalt compounds stabilized the surface over the winter, 

 but seedling growth was poor. None of the other compounds held the sand 

 through the winter and seedling establishment was no better than in the 

 control plot. 



3. Fences . 



A system of sand fences may effectively stabilize an area of blowing 

 sand for 1 or 2 years, but dune protection with fences usually becomes a 

 continuing process. Most fences tend to deteriorate because of corrosion 

 or decay as well as from damages from storms and man. Without continuing 

 maintenance and repair, the fences eventually fail and release the accumu- 

 lated sand. However, fences are more durable than most netting and mats. 

 Once a fence system is filled, it stops catching sand; the installation 

 of additional fence is required. Consequently, a sand fence is a tem- 

 porary dune stabilizer which must be supplemented or followed by longer 

 term protection such as planted vegetation, or using a sand-binding agent 

 where vegetation is not feasible, as in deserts (Kerr and Nigra, 1951). 



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