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Duckweed Control
Duckweed is an agressive pond
weed that covers a pond quickly with a green scum.
Email us for information
or with questions about your pond weeds. There is no charge for our pond services.
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Duckweed
(Lemnaoideae) is something I am actually very fond of...of course when a large
pond is infested with this plant it is no fun but in smaller water gardens and
backyard ponds duckweed can actually be a helpfull addition to the ecosystem!
Myself, I've actually gone to the garden store and bought a container full of
duckweed to add to my backyard pond...it cost me $5 and my wife asked me if I
was losing my marbles because duckweed can be found in almost any farm dugout
or stagnant swamp in the area! I am asked at least twice a week about methods
for controlling duckweed and other aquatic plants and algae of course.
In
a large pond duckweed can be an invasive plant that can cover the surface quickly
and it often is a real nuisance for the pond owner who suddenly can't see anything
in the pond!
Before we kill the duckweed with an aquatic herbacide, yes
there are some good algaecides that can eliminate duckweed from a pond, lets make
sure we actually do want to do it because this floating plant is actually a real
wonder of the pond! Duckweed can absorb a whole bunch of nutrients from the water
and will provide a great umbrella of shade for fish...so it will keep waters cooler
and also suck out phosphates from the pond. These phosphates and other nutrients
are the junk in the pond that cause the big blooms of floating green algae and
algae that grows on the bottom of the pond.
Why You May
Love Duckweed: Duckweed is a small delicate plant that drifts on
the pond surface, filling in spaces between the lily pads, creating a lovely green
blanket across the pond. This provides a lush habitat for frogs and fish and insects
of the pond. The layer of floating aquatic plants provides shade to the pond keeping
it cooler during stifling hot days of overhead sun. Waterfowl will feed voraciously
on the duckweed thus nest nearby and live in the pond. Duckweed grows rapidly
and absorbs mineral elements like nitrogen and phosphates from the water column
so it can be an important part in the aquatic rehabilitation of any pond or lake
as these nutrients can cause problems like algae and cyanobacteria. It is especially
good at removing ammonia from ponds. Beyond providing shade for fry bluegill and
a place to live for bullfrogs the duckweed helps reduce evaporation which can
be a problem in a clear pond without any cover to slow the rate of pond evaporation.
Sometimes just the rich green color of the plant alone is enough to make us feel
like our pond is a healthy and natural aquatic system! A bit like a stained glass
window on the pond, duckweed is a wonderful and beautiful plant, that with a bit
of understanding and acceptance is actually a very beautiful thing!
Why
You May Hate Duckweed: Duckweed is an invasive and agressive aquatic
weed that can rapidly multiply and if conditions are right will completely cover
a pond with a thick green cover of tiny green plants that are only a few milimeters
in size. The thick matting of pond weed can literally choke out a pond and if
conditions, temperatures and nutrient levels are right can completely hide the
water and create a cover that hides the pond and makes it almost unpleasant. Frogs
and ducks and turtles will live in what looks like a swamp! Maybe it provides
food for swans and geese and a mallard duck or two but it can choke out oxygen
levels.
There are Only Two Ways of Getting Rid of
Duckweed and Removing Blanket Weed (beyond just ignoring it) 1
- The Natural Way If the pond is small enough just the
best way to remove the small little flowering plant known as duckweed is to use
a fine meshed net and just manually remove it day by day, hour after hour, until
there is none left. Of course it is really tough to completey eradicate the problem
but you can keep it under control just like keeping the dandelions out of the
vegetable garden! You need a net with a long handle or a good quality aquatic
rake to harvest this pond weed if you want to deal with this problem naturally
or of course you can invite a family of ducks or geese or swans into your pond
and they will love the free food supply offered by these floating flowering plants
but you will still need the manual removal...if you don't want to accept the duckweed
or don't want to perform the manual work or invite the Duckworth family into the
pond then you need to go to the next option...
2
- The Chemical Way Aquatic algaecides and herbicides
are very effective at controlling duckwweds and other unwanted invasive pond species.
You should understand that such algae problems, well...it's not reaslly an algae
but an aquatic weed plant, if they are treated with herbiceds can lead to a dependance
or resistance and scientists generally agree that chemical selection pressure
that is applied applied to aquatic weed populations for a long enough period of
time eventually leads to resistance. This means that while the chemical pond weed
killer may work quickly and effectively for the first few years, unless you are
adding a positive treatment with aeration and natural beneficial bacteria you
will just be "chasing the dragon" so to speak!
Herbicides and
Chemicals for Killing Duckweed and Pond Weeds White Cap Selective Herbicide Control aquatic weeds and grasses in fresh
water ponds, lakes, and drainage/irrigation canals with WhiteCap™ SC selective
herbicide, a proven reformulation of the popular active ingredient fluridone.
WhiteCap effectively controls a wide range of floating, submersed and emersed
aquatic vegetation, including duckweed.
Controls: Duckweed, Hydrilla, Bladderwort, Watermilfoil, Naiad,
Elodea, Water-lily, Pondweed, and Coontail
See
The List of Aquatic Weeds that White Cap SC will control before you buy. Email
us if you're not sure! DOWNLOAD
THE WHITE CAPFULL INSTRUCTION, WARNING & WARNINGS
75'
x 75' Pond (.13) Acre 4 ft avg depth. - Amount required: 4 Ounces 105' x 105'
Pond (.25) Acre 4 ft avg depth. - Amount required: 8 Ounces 148' x 148' Pond
(.50) Acre 4 ft avg depth. - Amount required: 16 Ounces 208' x 208' Pond (1.0)
Acre 4 ft avg depth - Amount required: 32 Ounces |
8 Ounce Supply - White Cap Highly-Selective
Duckweed Herbicide - $229 Price
includes shipping. Item # PR-WC8 Apply 8
ounces per 600,000 gallons (1.9 feet acres) approx. Control aquatic weeds
and grasses in fresh water ponds, lakes, and drainage/irrigation canals with WhiteCap™
SC selective herbicide, a proven reformulation of the popular active ingredient
fluridone. WhiteCap effectively controls a wide range of floating, submersed and
emersed aquatic vegetation, including duckweed.
Controls: Hydrilla, Bladderwort,
Watermilfoil, Naiad, Elodea, Water-lily, Pondweed, Coontail and Duckweed
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16 Ounce Supply - White Cap Highly-Selective
Duckweed Herbicide - $439 Price
includes shipping. Item # PR-WC16 Apply 8
ounces per 600,000 gallons (1.9 feet acres) approx. Apply 16 ounces
per 1.2 million gallons (3.7 feet acres) approx. Control aquatic weeds
and grasses in fresh water ponds, lakes, and drainage/irrigation canals with WhiteCap™
SC selective herbicide, a proven reformulation of the popular active ingredient
fluridone. WhiteCap effectively controls a wide range of floating, submersed and
emersed aquatic vegetation, including duckweed.
Controls: Hydrilla, Bladderwort,
Watermilfoil, Naiad, Elodea, Water-lily, Pondweed, Coontail and Duckweed
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32 Ounce Supply - White Cap Highly-Selective
Duckweed Herbicide - $799 Price
includes shipping. Item # PR-WC32 Apply 8
ounces per 600,000 gallons (1.9 feet acres) approx. Apply 16 ounces
per 1.2 million gallons (3.7 feet acres) approx. Apply 32 ounces per
2.5 million gallons (7.7 feet acres) approx. Control aquatic weeds and
grasses in fresh water ponds, lakes, and drainage/irrigation canals with WhiteCap™
SC selective herbicide, a proven reformulation of the popular active ingredient
fluridone. WhiteCap effectively controls a wide range of floating, submersed and
emersed aquatic vegetation, including duckweed.
Controls: Hydrilla, Bladderwort,
Watermilfoil, Naiad, Elodea, Water-lily, Pondweed, Coontail and Duckweed
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128 Ounce (1 Gallon) Supply - White
Cap Highly-Selective Duckweed Herbicide - $1,795 Price
includes shipping. Item # PR-WC128 Apply 32
ounces per 2.5 million gallons (7.7 feet acres) approx. Apply 64 ounces
per 5 million gallons (15 feet acres) approx. Apply 128 ounces per 10
million gallons (31 feet acres) approx. Control aquatic weeds and grasses
in fresh water ponds, lakes, and drainage/irrigation canals with WhiteCap™ SC
selective herbicide, a proven reformulation of the popular active ingredient fluridone.
WhiteCap effectively controls a wide range of floating, submersed and emersed
aquatic vegetation, including duckweed.
Controls: Hydrilla, Bladderwort,
Watermilfoil, Naiad, Elodea, Water-lily, Pondweed, Coontail and Duckweed |
| |
|
Vascular
Aquatic Plants Controlled by WhiteCap | | Floating
Plants | Emersed
Plants | Submersed
Plants | Shoreline
Grasses | common
duckweed (Lemna minor) | spatterdock
(Nuphar luteum) | bladderwort
(Utricularia spp.) | paragrass
(Urochloa mutica) | | water-lily
(Nymphaea spp) | common
coontail (Ceratophyllum demersum) | | | common
elodea (Elodea canadensis) | egeria,
Brazilian elodea (Egeria densa) | fanwort,
cabomba (Cabomba caroliniana) | hydrilla
(Hydrilla verticillata) | naiad
(Najas spp.) | pondweed
(Potamogeton spp., except Illinois pondweed) | watermilfoil
(Myriophyllum spp., except variable-leaf milfoil) |
|
General Application of White Cap SC Aquatic Herbacide
& Algaecide Average
Water Depth of Treatment in Feet | Fluid
Ounces of WhiteCap per Treated Acre To Achieve Desired Herbicide Concentration:
| Application
Directions | 45
ppb | 90
ppb | 1 | 3.8
oz. | 7.7
oz. | ApplyWhiteCap
to the entire surface area of the pond.
Single Applications: Use the amount
of WhiteCap listed to give 45 to 90 ppb .fluridone in treated water. Higher rates
should be used for dense weed infestations, for dif.cult-to-control species, and
for smaller ponds (less than 5 acres in size and average water depths of less
than 4 feet).
Split or Multiple applications: Use when dilution of the
treated water is likely to occur. Do not exceed 90 ppb per annual growth cycle.
| 2 | 7.7
oz. | 15.7
oz | 3 | 11.8
oz. | 23.4
oz. | 4 | 15.7
oz. | 31.4
oz. | 5 | 19.5
oz. | 35.0
oz. | 6 | 23.4
oz | 46.7
oz. | 7 | 27.2
oz. | 54.4
oz. | 8 | 31.4
oz. | 62.4
oz. | 9 | 35.2
oz. | 70.1
oz. | 10 | 39.0
oz. | 78.1
oz. |
Susceptible
aquatic weeds absorb WhiteCap SC through the shoots and roots. For effective control,
contact of WhiteCap with the target plant must be maintained for at least 45 days.
Effective control is reduced if conditions exist that dilute the concentration
of WhiteCap in the water to below labeled rates. Apply WhiteCap as a surface spray
or subsurface injection at rates between 10 and 90 ppb for single applications,
or if multiple applications are made, do not exceed 150 ppb per growing season.
Water treated with WhiteCap SC at rates greater than 5 ppb must not be
used for irrigation of certain crops and newly seeded turf. If the concentration
of WhiteCap is less than 10 ppb, established tree crops, established row crops
or turf can be irrigated with WhiteCap treated water. Do not apply WhiteCap at
rates greater than 20 ppb within ¼ mile of any functioning potable water intake.
WhiteCap effectively controls a wide range of floating, submersed and
emersed aquatic vegetation, including Hydrilla, Bladderwort, Watermilfoil, Naiad,
Elodea, Water-lily, Pondweed, Coontail and Duckweed. Selective control. At low
use rates, it is safe for most native beneficial aquatic plants; WhiteCap SC selectively
removes the nuisance plants, while having little impact to desirable species
Complete
control. Readily moves and disperses throughout the water column,
providing complete and thorough control of target nuisance aquatic weeds Slow
control. Works slowly to remove excessive aquatic weeds with minimal impact to
aquatic ecosystems No human or livestock use restrictions. Water treated is potable
water safe and may be used immediately for human recreation and for watering livestock
Low use rates provide for cost-effective aquatic plant control DOWNLOAD
THE WHITE CAP COMPLETE INSTRUCTIONS IN PDF FORMAT Duckweed
Websites Here
are some websites we recommend if you are looking for more information. Washington
State Department of Ecology http://www.ecy.wa.gov/Programs/wq/plants/pla
ntid2/descriptions/lemmin.html Lemna minor (lesser duckweed)
and Lemna trisulca (star duckweed) Duckweeds are among the world's smallest flowering
plants. Individual lesser duckweed plants are tiny, round, bright green disks,
each with a single root.
USDA.gov http://plants.usda.gov/java/profile?symbol=LEVA PLANTS
Profile for Lemna valdiviana (valdivia duckweed) | USDA PLANTSA PLANTS profile
of Lemna valdiviana (valdivia duckweed) from the USDA PLANTS database.: Kingdom
Plantae – Plants Subkingdom Tracheobionta – Vascular plants Superdivision Spermatophyta
– Seed plants Division Magnoliophyta – Flowering plants Class Liliopsida – Monocotyledons
Subclass Arecidae Order Arales Family Lemnaceae – Duckweed family Genus Lemna
L. – duckweed Species Lemna valdiviana Phil. – valdivia duckweed
Wikipedia http://en.wikipedia.org/wiki/Lemnaoideae Lemnaoideae
- Wikipedia, the free encyclopedia24 May 2009 ... Duckweed is an important food
source for waterfowl and are eaten by humans in ... Classification of the duckweeds
in the family Lemnaceae is ... en.wikipedia.org/wiki/Lemnaoideae - Cached - Similar
- Lemna - Wikipedia, the free encyclopediaLemna is a genus of free-floating aquatic
plants from the duckweed family. .... Lemna Ecotox testing Duckweed growth inhibition
tests and standardisation ...
Guppies.com http://www.guppies.com/forums/showthread.php/duckweed-and-waterquality-18686.html Duckweed
and waterquality... a blessing in disguise. In fact, duckweed does much more than
suck up every particle of Nitrate in your tank. In depth study will reveal that
duckweed attacks ammonia vigorously, as well as Nitrates, Nitrites and just about
any other molecule with the nitrogen atom in it, lol. In addition to that, duckweed
sucks up phosphorus like a thin milkshake, actually removes suspended solids,
and organic material and even other toxins!. As if that weren't impressive enough,
it produces oxygen like nobodies business!
Eurasian Milfoil
Websites Here are some websites we recommend if you are looking
for more information. Washington State Department of Ecology
http://www.ecy.wa.gov/programs/wq/plants/weeds/milfoil.html
Once milfoil becomes well-established within a waterbody, it is difficult or impossible
to remove. In smaller waterbodies (350 acres or less), we have had some limited
success using an aquatic herbicide called Sonar® to remove milfoil. Recently the
state legislature gave limited approval for the use of 2,4-D to control pioneering
milfoil infestations. Other control methods include: Harvesting, rotovation (underwater
rototilling), installation of bottom barriers, diver hand pulling, diver dredging,
and in some very limited situations the use of triploid (sterile) grass carp.
We are investigating other biological controls such as the milfoil weevil. The
management of milfoil costs the state and private individuals up-to-one million
dollars per year.
Other Federal Government Websites
Eurasian
Water Milfoil USDA.
APHIS. Cooperative
Agricultural Pest Survey. National Agricultural Pest Information System. Photographs;
Distribution; Special Note: Links to other sites Eurasian
Watermilfoil - Invasive Plants: Changing the Landscape of America Federal
Interagency Committee for the Management of Noxious and Exotic Weeds. Identification/Description;
Photographs; Introduction History; Impacts; Distribution Myriophyllum
spicatum Integrated Taxonomic Information System. Taxonomy Eurasian
Watermilfoil - Plant Invaders of Mid-Atlantic Natural Areas (2002) DOI.
National Park Service and Fish and Wildlife Service. Identification/Description;
Photographs; Distribution; Introduction History; Impacts; Controls Whole-Lake
Applications of Sonar for Selective Control of Eurasian Watermilfoil, Feb 2001,
ERDC/EL TR-01-7 (PDF | 895 KB) United States Army Corps of Engineers.
Engineer Research and Development Center. Controls; Research Eurasian
watermilfoil - Aquatic Plant Information System (APIS) United States Army
Corps of Engineers. Engineer Research and Development Center. Environmental Laboratory.
Identification/Description; Introduction History; Impacts; Habitat; Distribution;
Dispersion; Controls Myriophyllum
spicatum L. (Eurasian Watermilfoil) - Noxious and Nuisance Plant Management Information
System (PMIS) United States Army Corps of Engineers. Engineer Research
and Development Center. Environmental Laboratory. Identification/Description;
Photographs; Introduction History; Impacts; Distribution Predicting
the Invasion of Eurasian Watermilfoil into Northern Lakes, Technical Report A-99-2,
Feb 1999 (PDF | 458 KB) United States Army Corps of Engineers. Waterways
Experiment Station. Controls; Research Foiling
Watermilfoil (Mar 1999) USDA.
Agricultural Research Service. Controls; Research Myriophyllum
spicatum Article Citation Search - AGRICOLA Database USDA.
National Agricultural Library. Research; Special Note: NAL
Catalog Search (resources) Myriophyllum
spicatum - Germplasm Resources Information Network (GRIN) USDA.
ARS. National Genetic
Resources Program. Taxonomy; Legal Aspects Eurasian
Watermilfoil - Biological Control of Invasive Plants in the Eastern United States
USDA. Forest
Service. Taxonomy; Identification/Description; Photographs; Distribution;
Introduction History; Impacts; Life Cycle; Habitat; Controls
Plant Profile for Myriophyllum spicatum - PLANTS Database USDA.
NRCS. National Plant Data Center. Taxonomy; Illustrations; Distribution; Legal
Aspects Myriophyllum
spicatum L. DOI.
Florida Integrated Science Center. Taxonomy; Identification/Description; Habitat;
Distribution; Impacts
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