Flowering Rush Seed Removal

August 31, 2017 Dear Friends of the Lake; Forest Lake is home to an invasive emergent plant called flowering rush that is spread via seed dispersal and rhizome (root) fragmentation. The control of flowering rush has been ongoing for 3 years.  The Comfort Lake-Forest Lake Watershed District (CLFLWD) manages flowering rush through herbicide treatments and manual flower cuttings. The purpose of the flower cutting is to remove flowers from the flowering rush plants before they can deposit seeds into Forest Lake.  In 2016, CLFLWD staff determined that the flowers on a single stem of flowering rush may produce up to 14,000 seeds annually.  Each of these seeds has the potential to start a new patch of flowering rush in Forest Lake or start an infestation of flowering rush in a new lake. On August 14th, 2017 the CLFLWD hired PLM Lake and Land Management to treat 40.2 acres of flowering rush in Forest Lake using the herbicide Diquat. The herbicide treatment occurred in similar areas of 2nd and 3rd lakes as those that were treated with herbicide in 2016. A second herbicide treatment will occur in late August or early September. On August 24th Jerry Grundtner with the FLLA and Mike Sorensen with the CLFLWSD collected flowers and seeds on August 24th, 2017. The entire shoreline of 2nd Lake and 3rd Lake was inspected by boat. When flowering rush flowers were observed, the flowers were carefully cut with a pair of household scissors and placed in a garbage bag inside of a plastic tub. We believe that we were able to remove 99% of the flowers but there may be some isolated flower heads still on the lake and there is still the potential for new flowers. In all, exactly 800 stems with flowers were collected. This can be compared to 276 stems with flowers that were collected last year. Since each stem may produce up to 14,000 seeds annually, collecting 800 stems may keep up to 11,000,000 seeds out of Forest Lake. With regard to disposal, all flowers and seeds have been transported in sealed containers to a location away from public waterbodies where they were burned. A second round of flower collecting will be performed in coming weeks prior to the second herbicide treatment. We ask that you do not cut any flowers if you see them as incorrectly cutting them will spread flowering rush even more. Figure 1. A sample of the 800 flowers that were collected on August 24th, 2017. Some of the flowers were still green with undeveloped seeds, while others were dry and easily dropped their seeds when touched.

Flowering Rush Treatment Notice

                                                                                                              August 10, 2017       

 

Dear Friends of the lake;

The treatment of flowering rush will occur with the first round of treatment on August 18th.  We wanted to give you notice so you are aware of the treatment when you see people and boats near your property. 

All of you who have prop

erty on the lake should have received a large postcard in the mail detailing the complete treatment process.  This will be our 4th year of treating flowering rush.  Even though we have not completely eradicated flowering rush we are making great progress.  This is a multiyear program and one that will continue for the next few years.  The 2nd round of treatment should occur in late August or early September.

We ask that you do not pull flowering rush or cut it as that only continues the spread of this invasive species.  If you are not certain what flowering rush looks like please refer to the postcard you received or look it up on the internet.

As a matter of fact we know that some lake residents are continuing to pull flowering rush because they did not know it was flowering rush.

This is an effort that the Comfort Lake - Forest Lake Watershed District, in conjunction with the City of Forest Lake, Forest Lake Lake Association, and MN Department of Natural Resources, will be conducting. The herbicide that will be used is called Tribune (active ingredient is Diquat) and will be applied by the licensed applicator company, PLM Lake and Land Management Corp. The combined acreage of all treatment areas totals 40.2 acres. A map of the treatment areas may be found below.    

We appreciate you cooperation with this effort and if you have any questions please do not hesitate to contact the Comfort Lake - Forest Lake Watershed District.

  

Sincerely

Jerry Grundtner

Board member  

FLLA - Forest Lake Snail Kill

                                                                                                              August 9, 2017       

 

Dear Friends of the Lake;

There has been significant discussion and questions regarding the recent dead snails that have been washing up on some of the shores around Forest Lake.  We asked the Comfort Lake Forest Lake Watershed District to investigate. 

The majority of snails washing up onshore are either Chinese Mystery Snails (Cipangopaludina chinensis) or Banded Mystery Snails (Viviparus georgianus). These are both invasive species of snails that were introduced to Minnesota via human activity. They were given the name "Mystery Snails" because for many years biologists didn't understand their life-cycle and their offspring seemed to mysteriously appear, fully-formed.

It is common for mystery snails to display a boom and bust population cycle where they grow extremely dense, then eat themselves out of their food supply (typically algae that is scraped from rocks and sometimes filtered from the water) and die back. It is likely that a massive snail die back is what is causing the snails to wash up onshore at Forest Lake. These types of large-scale die backs will continue to occur in Forest Lake's future, but it is hard to predict when.

Almost all of the snails that I have seen washing up on the shores of Forest Lake are no longer living. This means that chemical treatment is no longer possible. My suggestion is that lake residents either leave the dead snails in the lake or gather them up in a sealed bag and dispose of them in their garbage can.

These species are considered a Regulated Invasive Species by the Minnesota DNR and cannot legally be released into public waters (e.g. from an aquarium).

Additional information about mystery snails can be accessed at the following links:

Minnesota Sea Grant: http://www.seagrant.umn.edu/ais/mysterysnail 

Minnesota DNR: http://www.dnr.state.mn.us/invasives/aquaticanimals/chinese_banded_mysterysnails/index.html 

Sincerely

Jerry Grundtner

Board Member

FLLA - EWM Letter for second treatment

                                                                                                                     

                                                                                                                            August 4, 2017

Subject: Eurasian Watermilfoil (EWM) Treatment #2

Dear Friends of the Lake,

You may recall that 10 acres of Eurasian Watermilfoil (EWM) was treated in Forest Lake #1 on June 19th.

A follow-up inspection on July 11th indicated complete control of those 10 acres of heavy growth. However, during the lake wide inspection, additional moderate growth was identified in six other areas in Lake 1 and the entrance to Lake 2 for a total of 23 acres (see map below).

In order to help delay /prevent the spread of EWM to Lakes 2 and 3, these 23 acres will be double treated the week of August 7. A map of the treatment locations and a copy of the Public Notice from the CLFLWD and DNR appear below. The treatment was originally scheduled for the Week of Aug 1 but adverse weather/wind conditions forced the schedule to change to the week of August 7.

Thank you for your continued support of the Lake and your FLLA. If you have changed your email address, please let us know so you continue to receive timely FLLA information/broadcasts.

Steve Schmaltz

FLLA Board Member

Treatment Map and Public Notice appear below: