ABOUT US
Information
Officers
Members
Perspective

RESEARCH &
EDUCATION
Research
Education
Facilities
Cooperators

PLANT
MANAGEMENT
BMP Manual
Plant Pests
Management Options
Economics
Pesticides
Professional Help

INFORMATION
News
Calendar
Publications
Links

Journal of Aquatic Plant Management 39: 56-58.

Toni G. Pennington, John G. Skogerboe, and Kurt D. Getsinger

ABSTRACT

Greenhouse aquariums were used to evaluate the efficacy of the dipotassium salt of endothall in combination with other products against hydrilla (Hydrilla verticillata (L.f.) Royle.). Copper, diquat, or the mono(N,N-dimethylalkalamine) salt of endothall were combined with the dipotassium salt of endothall to determine if equal or improved hydrilla control could be obtained by combining products and using them in low concentrations. Treatments included 1, 2, and 3 mg dipotassium salt of endothall L^-1 used alone and in combination with 0.5 mg Cu L^-1, 0.5 mg diquat L^-1, or 0.2 mg endothall (mono(N,N-dimethylalkylamine salt)) L^-1. A 24-hour dissipation half-life was simulated and shoot biomass was harvested 3 and 6 weeks after treatment (WAT). Endothall (dipotassium salt) applied singularly at 2 and 3 mg L^-1 resulted in significant reductions in biomass 6 WAT compared to the untreated reference, or >95% control. All combinations significantly decreased the above ground biomass 6 WAT compared to the untreated reference. The dipotassium salt of endothall combined with copper or diquat provided >99% control even at the lowest rate of endothall (1 mg L^-1). Possible benefits of such applications include reduced herbicide quantity, improved selectivity and control of target plants, and reduced contact times.

For more information:

Pennington, Toni
Portland State University
Center for Lakes & Reservoirs
P.O. Box 751
Portland, OR 97207-0751
Email: toni@pdx.edu