the transplants excavated (Fig. 35). Therefore, to stabilize the dunes with vegetation, 

 mulching, or netting materials were needed to prevent sand movement for the first few 

 months after planting. 



Materials tested in 1972 as sand binders were a 7.5-ounce burlap and an open-weave, 

 0.5- by 2.5-inch netting (Fig. 40). Both materials were placed on the slopes of fence-built 

 dunes over horizontally transplanted culms of bitter panicum and secured to the sand with 

 6-inch staples. The open-weave netting was easier for the leaf blades of the transplants to 

 grow through without raising the netting off the ground. In the 1972 trials, the open-weave 

 netting proved satisfactory, containing sand in winds of 30 miles per hour, except on the 

 windward edge. Here, sand adjacent to the netting was excavated and the netting 

 undermined. 



In the 1973 plantings, about 60,000 square feet of the open-weave netting were used on 

 slopes of the North Section Fence including the foreslope. All plantings, including bitter 

 panicum and sea oats, were placed vertically and were untrimmed. The netting was placed 

 over the vertical culms, stretched tight and secured to the sand with staples. Since most of 

 the culms protruded from the ground and the netting was above the soil in many places, the 

 netting was raised 6 to 8 inches. Nevertheless, the mulch net was 100 percent effective in 

 preventing wind excavation of the transplants. None was lost on the critical foreslope 

 whereas unmulched areas suffered sporadic and locally severe wind erosion. Since vertical 

 placement of transplants by hand is less tedious and costly than horizontal hand planting on 

 slopes, and since the netting is effective when not completely in contact with the ground, 

 vertical transplanting followed by covering with the open-weave mulch net is recommended. 



In 1972, burlap proved to be a better sand binder than the netting but was more 

 expensive. Since the open weave is satisfactory, it is recommended over burlap. Both 

 materials begin to decay after 2 or 3 months, but in some areas the open-weave netting was 

 still intact and binding sand after 15 months. 



The netting is most easily spread with a four-man crew; two spread the netting over the 

 plants while the other two secure it to the sand with metal staples. The process requires 

 about 1 man-hour per 2,500 square feet of netting, or a single strip 667 feet long. To 

 completely cover a 400- by 50-foot dune with netting would require about 8 man-hours. 

 5. Postplanting Care. 



a. Irrigation. Preplanting irrigation is necessary on elevated surfaces, except after a 

 soaking rain. Since transplant survival of monthly plantings was positively correlated with 

 high soil moisture, it was believed a program of regular irrigation for several months after 

 planting would improve survival. Accordingly, all North Section Fence plantings were 

 irrigated for 3 months after replanting. Comparisons between irrigated and nonirrigated 

 plantings were made in 1973 at both north and south Padre monthly planting sites. Each 

 planting was irrigated several times per month for 3 months. During March through May, 



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