Vol. 15—1961 - NorthEastern Weed Science Society

551.
recei vcd from Messrs. John Gallagher and H'~~rold Collins of the -~mchem
Compnny, Ambler, Pennsylvania. Members of the Lake Hopatcong Advisory
Committee gave much of their time to this program. We especially
wish to acknowledge the services and cooperation of Mr. Emil Hermann,
Chairman of this Committee.
We are also grateful for the very active support received
from Commissioner Salvatore A. Bontempo; Kenneth E. Creveling,
Director,Division of Planning and Development; and Dr.A.Henton
Underhill, Director, Division of Fish and Game. Finally, we are
most appreciative of the many newspapers who reported our work in
such favorable light.
METHODSANDPROCEDURE
The sampling of the bottom of Lake Hopatcong in 1959 was
accomplished with an Ekman dredge and grapple hook, In the spring
of 1900 a Raythyon fathometer, model DEl19B, was employed with considerable
success in connection with . Ekman dredge, grappling hook and
Scuba equipment. For the most part, weed beds could be easily distinguished;
Potomogeton amplifolius, was easily recognized because
.of its height.
The treatment of the entire infested areas with herbicide
could have proven extremely costly. Fortunately, Lake Hopatcong can
be partially lowered and the decision was made to attempt to control
the milfoil in the shallow areas by freezing.~ It was decided to
lower the lake 7 feet for this purpose. The remaining areas of
infestation---mostly between the 7 and 14 foot contour lines---would
be treated with 2,4-Dgranules---about 750 acres.
A thirty-foot barge with an eight foot beam was made available
to the project by the Bureau of Navigation. A twelve by twofoot
platform was secured across the stern, at each end of which was
mounted a Gerber Seeder. These were powered by two l2-volt batteries
vrhLch lasted approximntely twenty hours before requiring a recharge.
Mr. Tom Haigh, Chief of the Forest and Parks Section, had had
considerable success in the control of milfoil in some of the
state-owned lakes with this technique. The procedure developed
is to allow the exposed bottom to freeze to a minimum depth of
four inches. Subsequent seed growth normally does not attain
sufficient height to be a problem in the same season.