67 



as floating plants, the farm configurations involving extensive sur- 

 face areas in which the plants were separated in shallow pens 

 might be visualized. 



This farming mode would require only floating pens and perhaps 

 nets to confine the seaweeds. The size of economically significant 

 units would depend on factors of productivity and price, but it is 

 possible that these would scale to fairly small holdings. 



If so, there is the possibility that waters within the State jurisdic- 

 tion could be used and that private holdings, through leases of 

 bottom lands, et cetera, would result. These, operating in the pri- 

 vate sector, could complement larger offshore holdings which 

 would be operated by the public utilities. 



Plants would be propagated and placed in pens for grow-out until 

 they reached optimal harvesting size. In a monoculture system, if 

 winter productivity were insufficient to warrant cropping, the 

 mature plants could be held in pens until growth resumed in the 

 spring. 



Alternatively, it may be possible to develop a polyculture system, 

 including some seaweed species that grow quite well in the winter. 

 This would permit year-round production. Harvesting would in- 

 volve surface skimming of the floating plants and their transport 

 by barge to shoreside digesters. 



Second level of technology alternatives we would consider a 

 medium level. This option envisions an intermediate between the 

 low-technology alternative and the macrocystis-like farm operating 

 on the west coast. It assumes that a long-stipe attached seaweed — 

 for example, laminaria — is found to be the most promising feed- 

 stock. This plant, not of the giant kelp dimensions but still requir- 

 ing anchoring of the holdfast in the fashion of macrocystis technol- 

 ogy, would probably be grown in farms farther offshore than the 

 low-technology alternative. 



This type of farm is complicated by having to maintain some 

 type of underwater anchoring surface to which the plants might be 

 attached. Such a more complicated structure is, of course, more 

 expensive to construct and maintain. This structure, therefore, is 

 seen as more capital intensive than the low-key technology system. 



The third, which we call high technology alternative, is as fol- 

 lows: This option implies more sophisticated technological systems 

 than the above and approaches the requirements of the west coast 

 macrocystis farm. Should macrocystis prove to have productivity 

 characteristics significantly superior to the native seaweeds and it 

 is decided to attempt introduction of this species to the east coast, a 

 number of alternatives might present themselves. 



Should a shorter, perhaps juvenile, plant perform adequately, a 

 shallower water farm might be preferable. If full-sized — that is, 15 

 meters or more in length — plants are required, farm sites necessar- 

 ily may have to be further offshore than for alternatives 1 and 2, a 

 factor that affects both the capital construction costs and the trans- 

 portation costs of the feedstock to shoreside digesters. 



Since, however, all alternatives involve transportation of wet 

 bulk biomass by barge, this latter becomes a marginal increase to 

 cost. Capital construction costs increase significantly as one moves 

 farther into the open waters of the North Atlantic. To develop 

 farms on the margin of the Continental Shelf will require substan- 



