D UDLEY P OND W EED M ANAGEMENT Lake Cochituate Watershed Council Symposium
Mike Lowery Wayland Surface Water Quality Committee 1
NO-GOOD LCWC SYMPOSIUM 5/15/2010
WEED GOES UNPUNISHED ?
D UDLEY P OND
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Some Dudley Pond Lots were raffle prizes at movie theatres!
LCWC SYMPOSIUM 5/15/2010
84 Acres
6-8’ Average Depth
Slow Water Turnover
DENSELY Settled – Summer camps of 30s became year round homes
Weed problems since 70s
Milfoil discovered in 1991
We’ve tried almost everything!
G OALS & S TRATEGY
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WHACK, YANK, and STARVE!
LCWC SYMPOSIUM 5/15/2010
Minimize long-term herbicide use
Use herbicide to regain control
Use hand-pulling & DASH for long term control
Spot treat with herbicide in areas diver’s can’t get under control – and keep hand pulling!
Pull out the root crowns post-herbicide
Get nutrients from runoff & septic under control
Town/State/Lake Association Partnerships
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2009 N EW G ROWTH ON OLD STEMS
Surprise? 2008 Fluridone didn’t kill all the plants.
ACT Inspection Visit
Ted & Allison provide examples & confer
Much new growth from old rootstock.
Herbicide didn’t kill strong-rooted survivors. Isn’t not just re-infestation. LCWC SYMPOSIUM 5/15/2010
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Interesting: Bad 2008 areas got sonar pellets and post-herbicide root crown pulling -and- were in good control in 2009.
Two big problem areas – developed late-season.
LCWC Symposium 5/15/2010
18,000 PLANTS PULLED 7,000 OLD - GROWTH SURVIVORS
2009:
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FALL 2009 – S URVEY R EMAINING P LANTS
At Season End: We knew where we had problems, and that hand-pulling alone in 2010 wouldn’t make it.
LCWC SYMPOSIUM 5/15/2010
Post-Diving survey - plants kept growing.
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2009 W INTER
PLANNING
Consensus: •Spot treat worst areas, hand pull remaining areas. •Remove Root Crowns after herbicide But: Order of Conditions allowed only 5 acres – we had 16+
LCWC SYMPOSIUM 5/15/2010
Ted, Allison & Mike agreed on the spot treatment areas.
2010 W INTER /S PRING – RFP & P ERMITTING
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Town Protocols We had to issue and RFP, get bids. ACT had low bid. Our permit only allowed 5 acre spot treatment – we presented to Conservation and they authorized 20. RFP
Select Vendor
LCWC SYMPOSIUM 5/15/2010
ConCom OK
2010 – H ERBICIDE S POT T REATMENT – M AY 19 TH
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No miracles:
Our experience: systemic herbicides don’t kill all the roots.
Late May/Early June: Spot treat 18 acres with triclopyr (Renovate OTF™). DPA funded 2 of the treatment areas: thanks! Total budget: $15,000
Conservation Commission just OK’d treating >5 acres.
Brown pellets – strongest action at weed base but will disperse throughout the pond. Will not control all milfoil
Excellent and selective response in North Pond, 2009 – native plants doing well.
Outlet will be closed, pond will be posted, 1 day noswim, no-boat – safety: fast airboat in use. No restrictions.
We’ll treat during the milfoil’s fast growth period.
5 day half life, effects seen in 1-2 weeks.
1,2 or 3 years - the plants grow back.
LCWC SYMPOSIUM 5/15/2010
2010 – H AND P ULLING
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U NDERWAY
NOW
You’ve seen the green markers – we’ve begun pulling the BIG plants we’d expect to come back.
We’re pulling ALL plants in the areas not planned for treatment
History Lesson: Areas pulled after Sonar in 2008 were less infested in 2009. So:
After 2010 herbicide we’ll yank-em while there down… Remove of root-crowns is cheaper and faster after herbicide, and we’re going to take advantage of that as we did in 2008. NO ONE ELSE DOES THIS
LCWC SYMPOSIUM 5/15/2010
Same $16K hand-pull budget as 2009
T HREE - PRONGED
WHACK, PULL, & STARVE
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Phosphorus is the limiting nutrient – Deprive milfoil of phosphorus, and it will not flourish.
APPROACH
We can whack them with herbicide
We can yank them out by the roots
BUT: If you feed them, they will come…
WSWQC and DPA and neighbors must work to limit inflows of nitrogen and phosphorus into Dudley Pond. LCWC SYMPOSIUM 5/15/2010
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W HEN YOU GET HOME …
PLEASE: Don’t Feed the Plants!
LCWC SYMPOSIUM 5/15/2010
Check the labels of your laundry & dishwasher products for phosphates – more than zero is bad for the pond.
Check when your septic system was last pumped out. Get it done.
Avoid phosphorus in lawn care products – if you use fertilizers, use slow-release organic products.
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Dudley Pond is a Category 5 (worst) impaired water body per MA DEP
TMDL – DOING THE SCIENCE
WSWQC has submitted a $50,000 grant request to MA DEP for federal EPA funds to conduct a TOTAL MAXIMUM DAILY LOAD study for phosphorus in Dudley Pond.
TMDL is a budget – a diet for phosphorus
“ORGANIC ENRICHMENT” DEP must develop plans for US EPA on Category 5 waterbodies.
LCWC SYMPOSIUM 5/15/2010
How bad is it?
How much ‘P’ comes in from where?
How much can it afford, what’s the target?
How could we lower it?
S OURCES OF P HOSPHORUS FOR D UDLEY P OND
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LCWC SYMPOSIUM 5/15/2010
Surface Runoff – lawn fertilizers, road crud
Septic Leachate
A Title-5 compliant system does VERY LITTLE to remove nitrogen and phosphorus.
Problem is the total load from all our systems.
Nitrogen flows easily in groundwater, Phosphorus is removed in loamy soils – our sandy soils don’t help.
Re-release from sediments
Animal waste & Plant matter
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D UDLEY P OND OF 2030 IS HAPPENING TODAY
Much of this we can control. If we can get the inflows under control there are ways to block re-release from sediments. LCWC SYMPOSIUM 5/15/2010
http://lakeaccess.org/lakedata/lawnfertilizer/p-diagram.htm
W HAT ABOUT THE C IRCULATORS ?
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LCWC SYMPOSIUM 5/15/2010
No effect on milfoil found in two year study.
Water clarity is good – that’s what circulators were originally designed for – but we have no data to prove causation.
Were just moved to shallower area near the Chateau with less water movement – now suggested by manufactures.
Under discussion:
2009 WAS GREAT –T HANKS FOR DPA SUPPORT !
LCWC SYMPOSIUM 5/15/2010
ALMOST
FINIS
2009 WAS FINE … W HAT W E W ORRY ?
Return of the Pond Beast taken last week LCWC SYMPOSIUM 5/15/2010
Wayland Surface Water Quality Committee
TAKE AWAY: G OALS & M ETHODS
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Whack ‘em. Yank ‘em, & Starve ‘em
LCWC SYMPOSIUM 5/15/2010
It’s a long fight – don’t get complacent
Run experiments – but always have a Plan B
Herbicide to bring it under control, hand-pulling & dash to keep it under control – spot treat if it gets away from you.
Yank the root crowns post-herbicide – its cheap & will minimize herbicide later.
NUTRIENT CONTROL! – Runoff, Septic