What is ProcellaCOR?
ProcellaCOR® is a targeted aquatic herbicide that affects invasive plants like milfoil while minimizing impacts to most native plant species. Prior to being approved for in-lake use by the U.S. EPA in 2018, it has been used for decades to control weeds in rice paddies grown for human consumption. It works at very low concentrations and is rapidly absorbed by targeted plants.
ProcellaCOR has been used successfully in several Maine lakes, including in Great Meadow Stream (Great Pond), where milfoil was reduced by over 97%.
Case Study
Prior to treatment in 2022, 7 Lakes Alliance removed up to 50,000 gallons of milfoil annually from Great Meadow Stream. Since treatment, the largest annual manual removal has been just 30 gallons.
How the Treatment Process Works
The application process may take anywhere from a few hours to several days, depending on the size of the treatment area. ProcellaCOR is commonly applied to water bodies using specialized airboats or shallow-draft boats, particularly in shallow, shore-side areas where invasive milfoil grows. The herbicide is rapidly absorbed by targeted plants such as variable-leaf milfoil and breaks down quickly in the water. Treated milfoil typically begins to decay within three weeks, with complete dieback—including roots—occurring within approximately six weeks.
- Application Method: The treatment involves a fan boat traveling slowly across the water, injecting the amber-colored liquid herbicide directly into the water, often just below the surface, via drop hoses.
- Targeting Milfoil: The herbicide is highly targeted to destroy invasive milfoil by causing the plant to grow rapidly, collapse, and die, rather than simply cutting it.
The goal of these treatments is to reduce milfoil growth to a level that can be managed sustainably over time.
We Know You Have Questions
FAQs
Frequently asked questions and concerns regarding ProcellaCOR being used on variable-leaf milfoil.
DEP Invasive Program
Program considerations with respect to herbicide use on established invasive aquatic plant populations.
Variable-Leaf Milfoil
Belgrade Stream is not only a breeding ground for milfoil, but it’s the source of other infestations.