nails), nonanchoring methods (sods and 

 cores), and also detached plants that 

 had been washed free of sediment, put 

 down on the bottom, and covered over 

 with sediment. Successful establishment 

 of plants was noted among the five meth- 

 ods. The best success was observed in 

 the detached plants washed free of the 

 sediment and merely covered over (Ta- 

 ble 2). This method may be usable in 

 Puget Sound, because the sand fraction 

 of the sediments in the eel grass is 

 fairly heavy, and even with a current of 

 2 or 3 knots, such as flows over that 

 garden, the sediment remains intact. 

 Sediments of eel grass meadows further 

 south at San Diego may have a larger 

 silt content, and the method probably 

 could not be used there. Zostera seems 

 to be moderately tolerant, and both 

 anchoring and nonanchoring devices can 

 be used for planting. If the silts are 

 too fine, anchoring devices can be used 

 for establishment. 



In Puget Sound where the sediments 

 are heavy, I can merely cover over the 

 plants, have them establish and fill up 

 a plot very quickly. Where the silts 

 are fine in eel grass meadows, anchoring 

 methods should be used. There is some 

 indication from these experiments and 

 others done in 1970 in another part of 

 Puget Sound, that transplantation done 

 in spring (March through May) gives the 

 best chance of successful establishment. 

 In Izembek Lagoon, Alaska, I have in- 

 stalled a number of eelgrass plots using 

 nails and rods as anchors and using 

 sods; I have also used the wire mesh 

 method. Almost universally in Alaska, 

 all anchoring devices result in low sur- 

 vival, while the use of sods and plugs 

 results in complete establishment. 



CONCLUSIONS 



In areas of environmental stress 

 which might occur in a local area or at 

 extreme limits of the distributional- 

 ecological range, such as in Izembek La- 

 goon for eelgrass or in Texas for Tha- 

 lassia and Halodule , seagrasses appar- 

 ently will not tolerate fixation to iron 

 anchoring devices for planting. In Puget 

 Sound, eelgrass establishes and grows 

 after being affixed to iron anchors and 

 planted as sods or plugs. I recommend 

 using the sod or plug methods because 



they allow seagrasses to be moved and 

 transplanted while keeping the root-soil 

 interface intact and were more success- 

 ful in the extreme geographical limits 

 of the area as well as the optimum 

 areas. In the optimum ecological area, 

 however, the plug method may be more 

 costly than simply planting detached 

 fragments. 



The manager should adopt whatever 

 method seems appropriate considering the 

 location, species concerned and sediment 

 type. I prefer the plug method for the 

 following reasons: (1) equipment which 

 removes the plugs from indigenous growth 

 is easily designed; (2) whole meadows of 

 indigenous growth would not have to be 

 greatly perturbed to get planting stock; 

 (3) a great number of plugs could be 

 easily transported; and (4) plugs can be 

 more easily installed than sods. 



Halodule invaded plots within 1 mo 

 in Boca Ciega Bay, Florida, after denud- 

 ing two large bottom areas within a 

 Thalassia meadow (Phillips 1960). After 

 5 mo the plots were half full of Halo- 

 dule , but there was no ingrowth of 

 Thalassia . Halodule in the Caribbean 

 seagrass system appears to be a pioneer 

 plant. Thalassia is a climax plant and 

 responds slowly and poorly to severe 

 perturbations such as siltation and 

 change in substrate type. Halodule ap- 

 pears to be stimulated by perturbations. 

 Based on field observations and trans- 

 plants I have made, I suggest using 

 Halodule in restoring an area. Halodule 

 is easily manipulated and will tolerate 

 wide salinity and siltation variation. 



Very little transplanting, except 

 that by Eleuterius (1974), has been done 

 on dredged materials. Eleuterius had 

 very little success with plantings of 

 Thalassia and Halodule on dredged mate- 

 rials in Mississippi Sound. Since 

 dredged material seems to have charac- 

 teristics different from the soil sup- 

 porting indigenous growth, a plug which 

 keeps the soil -root-rhizome interface 

 intact should have the best chance of 

 success. Also, I recommend the use of 

 Halodule if transplanting were to be 

 done in the South. The specific tech- 

 nique to be employed depends somewhat on 

 the nature of the soil. In Thalassia- 

 Halodule habitats I have seen silts too 

 fine to anchor the plants. Since anchor- 

 ing devices impede survival,! recommend 



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