Presentation Highlights:
A Quick Review of 2019
- In the spring of 2019, Aquatechnex applied SonarOne (Fluridone) throughout the North Arm to combat Curlyleaf Pondweed and Eurasian Watermilfoil.
- In the summer, ISDA applied Procellacor (Florpyrauxifen-Benzyl). This treatment targeted Eurasian Watermilfoil growth around the shoreline of the southern portion of the lake.
- ISDA conducted a Turion Assessment in Oct ’19. They sampled and counted the number of viable vs. non-viable turions at ~30 sites. The greatest number of viable turions came from the Sportsman’s Access area. This work sets up a baseline estimate of the extent of the Curlyleaf in the North Arm. It provides a point of comparison for future sampling, to be used as evidence of the success of herbicide treatments going forward.
Spring Treatment 2020
- Spring treatment will be in the North Arm only, targeting Curlyleaf Pondweed and killing any Eurasian Water Milfoil growing at the time of application.
- The treatment date targets the point at which germination is complete, and before turion development begins. Based on 2019’s weather, the application should take place the week of May 18. Stay tuned, as our mild spring could push that date out.
- ISDA will use Galeon (Penoxsulam) Herbicide. This herbicide has no drinking water or recreational restrictions. Irrigation restrictions include no irrigation of food crops or ornamental landscapes until the herbicide concentration is below 1 ppb; no turf watering unless levels are below 30 ppb. The application rate will be 10 ppb.
- ISDA will test for post-treatment residue 2, 14, and 28 days after treatment to monitor herbicide concentration.
2020 Survey Plans
- ISDA conducted a spring survey for Curlyleaf in the North Arm in March.
- An early summer survey of the littoral zone throughout the lake will assess Milfoil growth.
Summer Treatment 2020
- Procellacor treatments will take place after July 4, in the southern portions of the lake, if early summer survey results find Milfoil growth. If not, there will be no summer treatment.
- The North Arm will not be re-treated.
2020 Survey Plans cont.
- The 2019 Procellacor treatment areas will receive spring and late summer surveys to assess the impacts of treatment.
- Another Turion Assessment will take place in the fall in the North Arm to predict the long-term effect of the 2020 Galeon treatment.
The Invasive Aquatic Weeds Meeting concluded after an extensive Q&A period. Download the 2020 WeedTreatment-QA document for answers to questions from this session, as well as those submitted by participants before the meeting.
Watch the ISDA Annual Aquatic Treatment Plans web page for up-to-date plan details.