Coping with milfoil — what can and cannot be done. 



Eurasian milfoil, or Myriophyllum spicatum, is 

 an exotic, rooted water plant native to Europe and 

 Asia. It is an aggressive grower and can survive 

 in a wide range of temperatures, depths and salini- 

 ties. Generally the plant prefers water with less 

 than one-third to one-half salinity. Milfoil needs 

 light to live. 



Scientists speculate that milfoil came to the U.S. 

 in the 1880s on a foreign ship. Fragments of mil- 

 foil can root and begin new plants: the plant has 

 the capacity to grow 64,000 branches from one 

 branch in three months. Milfoil can also propagate 

 through seeds and winter buds. So it is not surpris- 

 ing that the weed quickly crept from New Jersey 

 to the Chesapeake Bay where it was a problem in 

 the 1950s and 1960s until it mysteriously died 

 away. Milfoil is now a pest from North Carolina 

 to Canada, Wisconsin, New York, Florida and in 

 the Tennessee Valley Authority Lakes. 



A bone-crunching hurricane would probably do 

 a lot to alleviate the milfoil infestation of Curri- 

 tuck Sound, but other less capricious methods of 

 control are available. All of the known controls, 

 however, are either costly, slow, risky or still in 

 the research stage. 



Chemical control with the herbicide 2,4-D has 

 already been tried on a very small-scale in North 

 Carolina. The state sprayed selected areas in 1968, 

 1971 and 1974. Nine hundred acres of Kitty Hawk 

 Bay which were sprayed in 1974 are still relatively 



Coinjock resident L. C. Barrow 



free of milfoil and other native plants. Martin 

 Point and Point Harbor, however, which were 

 dosed in 1971 and 1974, were buried in the weed 

 by the summer of 1975. 



No short-term harmful effects have been found 

 with 2,4-D according to Thayer Broili of the De- 

 partment of Natural and Economic Resources 

 (DNER). But there is always the danger of future 

 unknown impacts, so the state is reluctant to make 

 a full-scale chemical attack on the weed, Broili 

 said. 



"It's basically a stop-gap measure that would 

 have to be repeated every one, two or three years," 

 he said. "It could be used effectively in limited 

 areas, but I think we'd be in for a big mess if we 

 used it for a large-scale operation." Plus, 2,4-D 

 spraying costs an estimated $60 an acre, he said. 



Many Currituck and Dare County residents be- 

 lieve that salinity control is the answer to their 

 milfoil problems. Scientists agree that milfoil 

 could probably be controlled by raising the salinity 

 of Currituck Sound to one-third or one-half sea 

 strength. But the environmental and economic 

 implications are large. 



First the economics : In order to raise the salinity 

 of Currituck Sound and keep it at a level inhos- 

 pitable to milfoil, approximately $17 to $18 million 

 would have to be spent in the first year if pumping 

 were used. Another estimated $3.2 million would 

 have to be spent annually. It would take from 55 

 to 145 days to reach the correct salinity level and 

 constant maintenance would be required, accord- 

 ing to Ernest Knowles of the NCSU Center for 

 Coastal and Marine Studies. 



If an inlet were cut between the sound and the 

 sea, $10.2 million would have to be spent initially, 

 Knowles estimated. And constant dredging would 

 be needed to keep the inlet open, he said. 



Environmentally the picture is also gloomy, 

 especially for the bass fishermen and the local 

 people who depend on the bass fishing business: 

 milfoil may not like high salinity, but neither do 

 the bass. 



"It's obvious if we raise the salinity to levels 

 that will control the milfoil we'll eliminate the 

 fresh water species and the fisheries that go along 

 with it," said Don Baker, Chief of the Inland Fish- 

 eries Division of the State Wildlife Resources Com- 

 mission. "If we choose that route, it will be very 

 expensive. Besides, we're talking about inducing 

 changes we really won't be able to control. I don't 

 think we have the expertise to do it, or the financ- 

 ing." 



Mechanical mowing and harvesting of milfoil 

 is a control method now being practiced in parts of 

 the United States and Canada. Machines on gawky, 

 paddle-driven rafts chop the tops of the plants and 



(See "Looking," page 3) 



