Sunday, June 10, 2012

Herbicide Treatment Update and Weed "Outlook"

Dear Friends of the Lake,

On May 9th, Lake Management, Inc.chemically treated 155 acres of the invasive species Curly Leaf Pondweed(CLP). The treatment,materials and process was done under DNR approval and protocol. A map of the treated areas on Lakes 1,2 and 3 follows:



The treated areas were selected based on  a vegetation survey conducted by the consultant Steve McComas on April 10, 2012. The Goal was  to identify the CLP beds that represented the largest potential growth. As a result of the survey, treatment was shifted from some  areas previously treated for three years(and now controlled) to new CLP beds that had never been treated. New areas treated were on the south side of Lake 3 and some new areas on the west shore of Lake 1. Steve McComas was hired by the CL-FL Watershed District, Doug Thomas, Administrator, to improve the effectiveness of the CLP treatment/control program.


WHY?
Curly Leaf Pondweed (CLP) is a nuisance invasive weed  species in Forest Lake. It grows rapidly in less than 15 ft of water to form a mat like structure near the surface.  This formation restricts boating, water skiing, swimming and jet skiing. It chokes out native weed species. It dies in early July and floats to shore just in time for your 4th of July parties! The dead CLP  releases  phosphorus that supports summer algae blooms. Its turions( seeds) can germinate up to three years later.

WEED OUTLOOK

With an early ice out and early hot weather, the weed growth will be heavy this year. Treating 155 acres of CLP is not going to solve the problem of  weeds floating onto shorelines...although it does eliminate what would have been tons of weeds from  those 155 acres! There are a number of reasons why we will still see weeds floating to shore:

1. FL has 2300 acres of water. 1500 acres are less than 15 ft deep and can support vegetation growth. The City and FLLA treated 155 acres of invasive species CLP which is only 10% of the possible vegetation.There are other untreated beds of CLP that will die and float to shore in late June including CLP that is within 150ft of shore.Our treatment program is only authorized for "open water"( ie., 150ft or farther from shore).

2.Watercraft traffic (propellers cut weeds) and fisherman( anchors dislodge weeds) can send a lot of weeds to shore on a busy weekend.
3. Two native vegetation species common to FL are Coontail and Canada Waterweed(Elodea). Both have shallow root structures and are easily dislodged by boat traffic and/or storms /wind. These species can be the source of floating weeds....especially later in the summer.

SUMMARY

Tha City and the FLLA   treat 155-170 acres of CLP each year and this eliminates tons of weeds from floating to shore in time for your July 4th party. We  also eliminate 600 lbs of phosphorus from entering the lake from the decomposed CLP. However, their are 1500 acres ( out of 2300 total)  that are less than 15ft deep and can support vegetation growth. We are not allowed nor do we want to treat/kill native vegetation. So as a result of boat traffic, storm levels, fishing activity, and shallow rooted weed species  etc.,and the direction of the prevailing summer winds, everyone will have beach weeds sometime during the summer.
We  know this doesn't solve your problem but we hope it provides some perspective on the "weed" situation.

THANKS

Special thanks to Doug Thomas and the CLFL Watershed District Board for their support of our lake improvement efforts and to the City for partnering with us to maintain this valuable community asset.  None of the programs, however, could be implemented without the financial backing of you our Lake Association members. Thank you for your continuing support.
 
The FLLA Board
Steve Schmaltz, President

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