Vol. 15—1961 - NorthEastern Weed Science Society

567.
(such as, boating and water skiing) and lower sboreline real estate
values. In dense mats, conditions for mosquito breeding may occur
(SPfin&er 1959). , .
Considerable work already has been done 'on the control of
various species of watermilfoil in ponds and lakes by Younger (1959),
Boschetti (1959) t Hall (1960), Huckins (1960), aawlCol:titll (1HO). Since
tbese studies indicated that both si1'WlS and· 2)4-& can kill these' plants in
inland areas, our'main objective as to detend..' hcnr toapply these procedures
effectively in tidal sltuatSMIII 80 'that t1aey ~ld prO'91de satisfactory
control of Eurasian wateria1lfoll without being d.etriBJentai to native
waterfowl food plants or cOlllDercial and sPort fishery interests.
Studies on control of this plant have been a cooperative effort.
Personnel ~~ the Pa.tuxent Wildlife Research center furnished pertinent
data on identification, distribution, and eeolo&y of. Eurasian water"­
milfoU. ' Gerald H. Townsend, student assistant at Patuxent, and Richard
N. Smith, formerly with the Maryland Game and Inland Fish COIIIIl1ssion,
participated actively in applying and evaluating treatments, making
surveys, and tabulating data. Charles r. Noble and Houston C. Phillips
of the Pea Island National Wildlife Refuge in North Carolina assisted in
control teats conducted 1n that area. Francis Beaven of the Maryland'
Department of Research and Education and Dexter S. Haven of the Virginia
Fisheries Laboratory participated in field studiea and conducted pre­
11m1uary investigations on the toxicological effects of control procedures
on fish, crabs, and oysters. Edgar H. Holli8 of the Maryland Department
of Tidewater Fisheries and Royston Medford of the Bureau of Coumereial
Fisheries sUpplied information on distribution of the plant in MarY1.and.
ChelUcal companies, including Allied Chemical Corporation; Amcbem
Products, Incorporated; Chipman Chemical COIDp4ny, Incorporated; Diamond
Alkalt Co.qtpany; Dow Chemical Company; Pennsalt Chem1c~ls Corporation; .
and. B.euor-Hill Corporation furnished materials and technical assistance.
STUDYPltOCEDUR.E
~tudies were ~onducted in Dundee and salq.eter Creeks and on
the SUsquehAnna Flats in the upper part of Chesapeake Bay and on Lower
Machodoc, Nailj81l1OYand Piccowaxen Creeks off the Potamac River. tidal
fluctuation b. these areas varied from 2 - 2 1/2 feet. Other tests were
made in a fre8hwater impoundment at the Pea Is land. Refuge. ""
MOst of the tests consisted in the app1ication'~f granUles of
attaclay !mpl'.'egnated with herbicide because liquid carried materials are
more apt to be traDspot:'ted' away by the tide. Also" unPUblished work has
8hown ~ that certaln liquid cmiers sometimes are harmful to aquatic
animal life. Not only can they increase the tosicity· of' the compound,·
but they can cause. an unpleasant flavor,' as in"oysters subjected to oil
at concentrations aa law &8 I a.lIon to anacre.'