VI. MAINTENANCE 



Once a site is planted, it will be necessary to keep it free from debris 

 that might smother the plants, especially during the first two growing 

 seasons. Litter such as wood, styrofoam, algae, and dislodged submerged 

 plants forming a strandline should be removed in both the fall and the spring. 

 Another source of possible plant damage in some regions is predation from 

 Canada and snow geese which are fond of the roots and rhizomes of marsh 

 plants. Rope fences on the seaward edge of the marsh will exclude waterfowl 

 during the first few growing seasons. Fences should consist of wood, metal, 

 or plastic pickets strung with nylon rope spaced at 6-inch (15 centimeter) 

 intervals from the sediment surface to mean high water (E.W. Garbisch, 

 Environmental Concern, Inc., personal communication, 1977). 



VII. COSTS 



The principal cost of a project (unless site preparation or temporary 

 protection is required) is the labor required to obtain or produce propagules 

 and plant them. Harvesting and planting must usually be confined to about a 

 5-hour period per tide which substantially affects the cost of labor. Smooth 

 cordgrass. Pacific cordgrass, Lyngbye's sedge, and tufted hair grass sprigs 

 can be harvested, processed, and planted by hand at a rate of about 10 man- 

 hours per 1,000 sprigs. Using plugs of any species is at least three times 

 more time-consuming than using sprigs (30 man-hours per 1,000 plugs). Pre- 

 paring and planting nursery seedlings of any species takes about 23 man-hours 

 per 1,000 seedlings. To estimate labor requirements for a particular project, 

 first determine the number of planting units required as follows: 



No. of planting units = area of planting x 



(plant spacing)^ 



(Plant spacing for erosion control projects is typically 1.5 feet.) 



Second, determine the labor required to prepare and plant these units as 

 follows: 



T , . , .T ^ 1 . . man-hours 



Labor required = No. of planting units x 



1,000 planting units 



(As noted above, sprigs require about 10 man-hours per 1,000 planting units, 

 plugs about 30 man-hours per 1,000 planting units, and nursery seedlings about 

 23 man-hours per 1,000 planting units.) 



The cost of fertilizer varies but will probably cost no more than $50 to 

 $100 per acre (1980) including labor or about 5 to 10 cents per linear foot 

 for a 30-foot-wide (10 meter) planting. Slow-release fertilizer is more 

 expensive, about $500 to $1,000 per acre or $0.50 to $1.00 per linear foot for 

 a 30-foot-wide planting. However, the use of slow-release materials will 

 eliminate the need for postplanting fertilizer applications. 



Figure 10 compares planting costs per foot with the costs per foot of 



several alternative structural devices. (Labor costs assumed to be $15 per 



hour plus 100 percent overhead. ) Vegetative stabilization is lower in cost 

 than any structural erosion control measure. 



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