Archive for the ‘Management’ Category

2015 Year End Milfoil Report Now Available

Friday, July 8th, 2016

Better late than never?

The Lake Fairlee Association holds a permit from the State of Vermont that governs all phases of our milfoil control activities – including hand pulling, suction harvesting, bottom barriers, herbicide treatment, and our greeter/prevention program.  This permit requires that we conduct annual surveys of plant life in the lake, and that we file a report with the state annually.

Since 2010 we have contracted with (licensed) companies to conduct our various milfoil control activities, and they have been primarily responsible for filing these annual reports. The 2015 report was not completed and filed until July this year.  Nonetheless it contains lots of detail about Lake Fairlee’s milfoil program.  We provide it here for your information.

Click on image to download report (.pdf)

Click on image to download report (.pdf)

More about the Herbicide Application

Thursday, June 18th, 2015

renovate otfThe herbicide is delivered in 40 pound bags that look like they might contain fertilizer.  Although we are only putting a very little bit of chemical in the water, we want it to be absorbed at or near the roots of the plants so far as possible.  So the chemical comes blended in pellets of chunks of clay, which will sink to the bottom before dissolving and releasing their active ingredient.

P1050350_SnapseedIt is poured into hoppers on the back of the boat.  Under each of these there is a powered spinning disk that spreads the pellets several yards either side of the boat.  (click on the thumbnail to enlarge)  The driver follows a programmed course that zigs and zags back and forth to cover the designated treatment area.  And the speed of the boat and the hoppers’ flow rates are regulated to ensure that the herbicide is delivered at the desired concentration.

No Herbicide Treatment in Summer of 2014

Thursday, May 1st, 2014

The Lake Fairlee Association has had variable success dealing with the invasive Eurasian milfoil that has invaded our lake and many others around the region.  We do other things as well – we promote safe boating practices and encourage shoreline planting that is best for the health of our lake.  And we continue to build community and provide social opportunities around the lake — as we did 20 and 40 and 60 years ago, long before the advent of the milfoil.

In 2010 we successfully treated all of the affected areas of the lake with the herbicide triclopyr.  Within weeks 99% of the milfoil was rotting on the bottom of the lake.  Unfortunately the herbicide only kills the milfoil that extends into the water column; the extensive root system persists.  Also the small fraction that survived can reproduce by seeding, propagation, or fragmentation.  And new milfoil can be introduced by transient boaters or even waterfowl.

Management of milfoil is heavily regulated by the State.  That is not a complaint, as we are in favor of strict controls of what goes in the lake, particularly of herbicides.  But it means that politics and bureaucracy are involved at every turn in our attempts to control the weed.  Milfoil again affects significant portions of the lake, but we will not be treating it with herbicide this year.  We will negotiate with the State and attempt to duplicate our 2010 success in 2015.

Extent of Milfoil Growth at the end of 2013

Tuesday, February 25th, 2014

This is what was on our minds as we approached the 2014 season.September 2013 Survey

September Survey Map

Some good news . . . and some bad

Saturday, June 22nd, 2013

We have receive the results of tests run on samples taken from the lake on June 17th.  We tested the same five locations, and none contained more than 15  ppb (parts per billion) of triclopyr.  Therefore the “voluntary” restriction on drinking and cooking with water from the lake has been lifted.  Again we remind you that we recommend that you never drink lake water without treatment or filtration.

At the same time we have been informed that, because triclopyr was found at detectable levels at the downstream testing site, we are required to extend the restriction (again, voluntary) on irrigation an additional 1.5 miles downstream. In accordance with the terms of our permit, certified letters have been sent to property owners downstream as far as 621 Barker Road.

[the following is the opinion of the author, who is not an expert]  We believe that the State’s restriction on irrigation is overly broad.  Triclopyr is an effective herbicide for dicots.  It is not toxic to monocots (e.g. grasses) or Gymnosperms (e.g. conifers).  There is no danger from irrigation of lawns.  In addition, the requirement that the concentration of triclopyr be less than one ppb (part per billion) Before the restriction is lifted seems unnecessarily low.  We would welcome some quantitatidata justification.

 

Press Release from VT DEC

Friday, May 31st, 2013

[The following was issued by the Vermont Department of Environmental Conservation on Friday, May 31]

Use Restrictions Recommended for Lake Fairlee Following Milfoil Treatment May 31, 2013

Fairlee, VT – The chemical herbicide triclopyr was selectively applied to Lake Fairlee on Friday, May 31, to control the aquatic invasive plant Eurasian watermilfoil, Myriophyllum spicatum in dense beds around the lakeshore.

Originally scheduled for Thursday, the application was delayed until Friday. Local residents were informed of the application, which was authorized by the Department of Environmental Conservation’s Aquatic Nuisance Control Program, before it was scheduled.

Lake Fairlee is not officially closed. However, as a precautionary measure, under advice from the Vermont Department of Health, the public is strongly encouraged to comply with the following voluntary use restrictions for Lake Fairlee and the waterway downstream to its confluence with the Ompompanoosuc River:

  • No use of the water for any purpose today (Friday, May 31) and tomorrow (Saturday, June 1)
  • No use of the water for drinking, or for food or drink preparation until further notice.
  • No use of the water for recreation (swimming, boating, fishing) until Sunday, June 2.
  • Other domestic uses, other than for drinking, or for food or drink preparation may resumeSunday, June 2
  • No use of water for irrigation for 120 days or until further notice.

Triclopyr is a highly effective broadleaf herbicide that is used to control a variety of nuisance and invasive aquatic plant species, and is very selective to Eurasian watermilfoil. Triclopyr is most effective when applied when Eurasian watermilfoil is actively growing, thus a late spring treatment is generally most effective.

The displacement of native aquatic plants in particular has been seen in lakes in Vermont where Eurasian watermilfoil has become widespread and dense. By using this herbicide selectively Eurasian watermilfoil growth can be controlled manually in other areas of the lake and improve habitat for the native aquatic plants in the lake. Uncontrolled, Eurasian watermilfoil will eventually out-compete the native plants. Native plants will not be significantly affected by this treatment.

Please contact the Lake Fairlee Association, via Skip Brown at 802-333-4541 or Suzy Kerr at 802-333-9079 for additional information.

Up to date information may also be obtained by visiting the Lake Fairlee Association webpage http://blog.lakefairlee.org/?page_id=87

Visit Vermont’s Aquatic Nuisance Control Program webpage at: http://www.anr.state.vt.us/dec/waterq/permits/htm/pm_anc.htm

Milfoil Treatment Update – September 2012

Sunday, September 30th, 2012

[ What follows are the notes from the divers submitted after their visit of September 11-13. ]

We extracted a total of 31 panels (est. just over 18,000 sf) and associated metal from sites shown in red. The only remaining panels that I am aware of are at the Middle Brook site (site 14 on this map).

Additionally, we hand harvested a total of 3,138 plants from 8 sites.
We did not visit (DNV) several of the sites in the south basin, but it is expected that there is growth at those sites.

caption

Of the sites/areas we did work, milfoil growth does seem to be increasing. As examples consider the following observations:

Site 6 yielded over 1000 plants and these were noted to be spread throughout the bay, as deep as 15′ generally mixed among dense growth of native species.

Site 15, originally just the boat launch at Aloha Hive, is now spread a bit South and well East of the launch scattered to moderate all the way to the southernmost portion of the swim docks transitioning from flat silty bottom to moderately steep and rocky area.

Site 5 was not fully cleared, but plants are moderately scattered from the swim platform off the point northward a full three properties (to the large yellow house with white trim (which also has a very loud Chocolate Lab)). We worked the northernmost reach of that site off of the yellow and white house.

And while it is not noted on my map, there are also scattered milfoil plants just outside of the public boat launch.. primarily on the northern bit in the shallow rocky area just outside of the launch itself.

In general, it seems that milfoil is again starting to grow/spread faster than we are clearing it… though that conclusion is necessarily tentative. Once the full survey is conducted this week we’ll be able to put together a game plan for 2013. I would anticipate however that the 2013 plan include more robust harvesting 2-3 times throughout the summer (i.e., perhaps as much as a concentrated week-long efforts instead of spreading out 2-day visits). We’ll revisit this idea once the survey/maps are completed.

 

Milfoil Treatment Update – August 2012

Monday, August 6th, 2012

After learning of the additional requirements imposed on our planned herbicide treatment of the milfoil near the mouth of Middle Brook, we elected to use hand pulling and possibly bottom barriers this year.  It was our hope that we could clear the other locations in the lake and then treat that dense patch with triclopyr early next summer. LINK

We have contracted with Lycott, Inc., to provide a dive team to hand pull the E. milfoil plants that are not part of that dense patch.  They have visited the lake twice this summer, and plan to return one more time.  After each visit they provided us with a detailed summary of the number of milfoil plants they removed and their locations.  In the maps below the fifteen sites where milfoil had been identified during the May survey are labeled.

On their first visit, June 14th and 15th, they cleared all of the sites except site 14, which is the dense 8+ acre patch near the mouth of Middle Brook shown in the map inset.  In all, they pulled 2787 plants.  Their second visit was July 20th and 21st.  This time they were not able to clear all of the outlying areas.  The number of plants had increased significantly during the intervening five weeks.  They removed a total of 5159 plants from the fourteen sites this time.  Even so, they were unable to completely clear sites 5 and 13 due to time constraints.

The numbers in the circles indicate plants collected each visit.  The letter C preceeding the number indicates that the area was completely cleared. Where there is an R, it means that the number of plants were removed, with other plants remaining.  The third and final visit by the divers is planned for early September.

June 14-15. Click above for larger image.

 

July 20-21. Click above for larger image.

We are pleased by the quality of work done by Lycott’s divers.  The detailed reporting is certainly refreshing, giving a count of individual plants removed.  For earlier years we have quantities measured in cubic yards and bushels.  Figuring a conversion factor is something we have yet to accomplish.

VPR article on Marsh Mermaid Weed

Thursday, June 28th, 2012

Vermont Public Radio interviewed lake residents Dale Gephart and Skip Brown and did a piece on our issue this summer with  proserpinaca palustris.  You can read it on their blog HERE.  There is a button near the top left which will allow you to hear the entire piece.

Mermaid Weed – A Correction

Tuesday, May 22nd, 2012

In an earlier post we mistakenly stated that Proserpinaca palustris is categorized “S1” by the State of Vermont.  This would mean that it is “Very rare (Critically imperiled): At very high risk of extinction or extirpation due to extreme rarity (often 5 or fewer populations or occurrences), very steep declines, or other factors.”

In fact P. palustris is listed as “S2”, a slightly less extreme category, meaning “Rare (Imperiled): At high risk of extinction or extirpation due to very restricted range, very few populations (often 20 or fewer), steep declines, or other factors.”

The source for this information is the Natural Heritage Information Project of the Vermont Department of Fish and Wildlife.  You can find it on the 13th page of their document Rare and Uncommon Native Vascular Plants of Vermont.  An explanation of the status codes and their legal implication s can be found here.