Water
Hyacinth (Eichhornia
crassipes) |
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(Photo credit: University of Florida, IFAS, Center for Aquatic Plants, http://aquat1.ifas.ufl.edu/hyacin2.html) |
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DESCRIPTION
Water hyacinth (Eichhornia crassipes) has been called the world's
worst aquatic weed. It is a free floating water plant that is native to South
America. It can vary in size from a few inches tall to over
three feet. This plant has blue-green leaves, thick stalks and
a showy purple or lavender flower. It thrives in tropical regions
and in waters that are high in nutrients. Its beautiful, large
purple and violet flowers have made it a popular ornamental, and the
plant is now naturalized in most of the southern United States. It reproduces mostly by clonal propagation, but seeds also play a role
in its survival and colonization. Massive weed colonies can grow when introduced
into areas that are conducive for their proliferation. In addition, infestation
can occur given a disruption in the natural ecological balance by human
activities such as impounding of flowing waters by dams, channeling and allowing
the buildup of eutrophication.
Identification
- free-floating, robust plant
grows up to three feet off the water's surface
- shiny green leaves are round
to oval, four to eight inches in diameter, with gently
incurved sides
- leaf veins are dense and
numerous so leaves stand erect
- stalks are bulbous and
spongy, and help keep the plant buoyant
- flowers have six petals,
purplish blue or lavender with yellow
- several flowers grow at the
top of a single stalk
- a mass of fine purplish
black and feathery roots hangs in the water underneath the
plant
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(Source: 1. King County, WA Noxious Weed Control
Program, http://splash.metrokc.gov/wlr/waterres/smlakes/hyacinth.htm;
2. Integrated Pest Management Florida, http://www.ifas.ufl.edu/~FAIRSWEB/IPM/ipmfl/v2n4/hyacinth.htm).
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IMPACTS The primary attribute of water
hyacinth is its ability to grow under a wide range of nutrient and environmental
conditions. The plant is able to develop at an astounding rate, effectively
out-competing other native aquatics. Its growth rate is among the highest of any
plant known: hyacinth populations can double in as little as 12
days. This rapid growth can cause an imposing
amount of biomass. The level of biomass accumulation will determine its nuisance
value and the impact on water quality. Excessive infestation by this weed can
severely constrain human activities, affecting accesses to water, navigation,
irrigation and fisheries. In other words, Incredibly dense mats of free-floating
vegetation block boat traffic and prevent swimming and fishing, and
keep sunlight from reaching the water column and submerged plants.
(Source: 1. King County, WA Noxious Weed Control
Program, http://splash.metrokc.gov/wlr/waterres/smlakes/hyacinth.htm;
2. Integrated Pest Management Florida, http://www.ifas.ufl.edu/~FAIRSWEB/IPM/ipmfl/v2n4/hyacinth.htm).
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ORIGIN
Water hyacinth is native to South America, and was
introduced to the United States in the 1880s. It probably originated in
the swamps associated with the great river systems of northern and central South
America. Water hyacinth has not yet (1998) been found in the wild in Washington
State, but has been sold as an ornamental in plant nurseries. Its
use as an ornamental means that it could be introduced to our lakes
and rivers, and this is expected to be its primary method of spread.
(Source: 1. King County, WA Noxious Weed Control
Program, http://splash.metrokc.gov/wlr/waterres/smlakes/hyacinth.htm;
2. Integrated Pest Management Florida, http://www.ifas.ufl.edu/~FAIRSWEB/IPM/ipmfl/v2n4/hyacinth.htm).
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DISTRIBUTION |
Link to USGS International Program at
the EROS Data Center
Link
http://edcsnw3.cr.usgs.gov/ip/hyacinth/winam2.html |
Kisumu Bay, December, 1997
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Kisumu Bay, February 2000
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According to the website
of USGS International Program, the photographs at left were taken
from nearly the same point on the south shore of Kisumu bay. The
December 1997 photo shows an enormous mat of nearly pure water
hyacinth. By February 2000 hippograss had become established
in the area formerly dominated by water
hyacinth. |
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Control
Water hyacinth Water
hyacinth can be controlled by harvesting, aquatic herbicides, and
biological control agents. Locally, the best way to manage water
hyacinth is to prevent it from becoming established. Plants
purchased at local nurseries should be disposed of away from
waterbodies.
Mechanical Control:
Swamp Devil & Harvester
The
Swamp Devil is a heavy duty aquatic vegetation cutter that
features tow blades at the front which measure 2.4 meters
across. It had a 234 horsepower engine and can easily shred
trees up to 15 cm in diameter. It will be collecting and removing a portion of the chopped
debris. |
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The
harvester has the ability to carry four tons of vegetation on
board in a single load. Depending on the weight and
volume of the vegetation and the distance to the shore, the
harvester can potentially remove 16 to 32 loads of chopped
hyacinths in eight hours. |
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Water Hyacinth
Uses:
As
Fodder for Pigs |
Boiled water
hyacinth is used in Southeast Asia as a feed for pigs. The
plants are chopped and sometimes mixed with other vegetable
wastes, such as banana stems, and boiled slowly for a few
hours until the ingredients turn into a paste, to which oil
cake, rice bran and sometimes maize and salt are added. The
cooked mixture is good for only three days, after which it
turns sour. A common formula is 40 kg of water hyacinth, 15 kg
of rice bran, 2.5 kg of fish meal and 5 kg of coconut meal. |
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Products
from Water Hyacinth - Ryan Foundation
Link |
Products
from Water Hyacin: Hyacinth Crafts
Link |
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(Source: 1. Integrated
Pest Management Florida, http://www.ifas.ufl.edu/~FAIRSWEB/IPM/ipmfl/v2n4/hyacinth.htm;
2. Water Hyacinth Information Page: http://homepage.westmont.edu/u/outside/phil.soderman/www/);
3.
Aquatic
Plant Harvesting. Lake Victoria, Kenya,
http://www.water-hyacinth.com/)
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Flower spike/photo BMR |
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Invasive Nonindigenous Plants in
Florida: University of Florida, IFAS,
Center for Aquatic Plants
http://aquat1.ifas.ufl.edu/hyacin2.html
This website provides information about brief history, identification, control
methods, and downloadable information sheet.
Water
Hyacinth Information Page: Phil Soderman, Sterling Nursery, Carpinteria,
California
http://homepage.westmont.edu/u/outside/phil.soderman/www/
This site shows a collection of Water Hyacinth information including Water
Hyacinth Information; Constructed
Wetlands Information; San
Pasqual Aquatic Treatment Facility; Water
Hyacinth uses; Water Hyacinth COMPOST References, and so
on.
Aquatic
Plant Harvesting. Lake Victoria, Kenya
http://www.water-hyacinth.com/
This site introduces special equipment to chop water hyacinth. In addition, the
site includes information about challenges, solution, hyacinth uses and so
on.
Water
Hyacinth: University of Waterloo (Canada) and FIRRI (Uganda) Collaborative
Project
http://freespace.virgin.net/ae.williams/Work.htm
This sites introduces general information related to water hyacinth and project
information conducted by Dr. Adrian E. Williams.
Remote
Monitoring of The Water Hyacinth Infestation of Winam Gulf, Kenya: USGS
International Program
http://edcsnw3.cr.usgs.gov/ip/hyacinth/winam1.html
This website introduces severe
water hyacinth infestations on Winam Gulf, in the Kenyan portion of Lake
Victoria during the late 1990s and early 2000. This site shows a series of Radarsat
images and other real data related to water hyacinth.
Weeds
on the web: Wildland Invasive Species Program
http://tncweeds.ucdavis.edu/esadocs/eichcras.html
This website includes links to all our resources specific to individual invasive
species, and provides useful information and pictures related wild land invasive
species including water hyacinth.
King County
Water & Land Resources Division, Lake Stewardship
Program
http://splash.metrokc.gov/wlr/waterres/smlakes/hyacinth.htm
This site includes several good descriptions including history, method of
spread, methods of control, and identification.
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More information about water
hyacinth, as contained in the Langeland/Burks book, Identification
& Biology of Non-Native Plants in Florida's Natural Areas (Free):
University of Florida.
To download PDF file
http://aquat1.ifas.ufl.edu/hyacin2.html
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Weed
Control Methods Handbook: Tools and
Techniques for Use in Natural Areas
Link
http://www.dnr.state.wi.us/org/land/er/invasive/info/loose2.htm
Online brochure provides very
detailed general and regional information, current extent, and
control methods. |
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Weed
Control Methods Handbook: Tools and
Techniques for Use in Natural Areas
by Mandy
Tu, Callie Hurd,
& John M.
Randall.
(Free):
Updated version from April 4, 2001).
Link
http://tncweeds.ucdavis.edu/handbook.html
This online handbook provides very
detailed information about herbicides and control techniques.
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Introductory
Material |
Table
of Contents, 2 pages. (Word,
Acrobat) |
Introduction,
3 pages. (Word,
Acrobat) |
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Chapters |
Chapter
1 - Manual and Mechanical Techniques, 7 pages. (Word,
Acrobat) |
Chapter
2 - Grazing, 6 pages. (Word,
Acrobat) |
Chapter
3 - Prescribed Fire, 10 pages. (Word,
Acrobat) |
Chapter
4 - Biocontrol, 24 pages. (Word,
Acrobat) |
Chapter
5 - Guidelines for Herbicide Use, 18 pages. (Word,
Acrobat) |
Chapter
6 - Herbicide Properties, 13 pages. (Word,
Acrobat) |
Chapter
7 - The Herbicides |
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Herbicide
Table, 4 pages. (Excel,
Acrobat) |
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A:
2,4-D, 11 pages. (Word,
Acrobat) |
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B:
Clopyralid, 6 pages. (Word,
Acrobat) |
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C:
Fluazifop-p-butyl, 6 pages. (Word,
Acrobat) |
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D:
Fosamine Ammonium, 6 pages. (Word,
Acrobat) |
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E:
Glyphosate, 10 pages. (Word,
Acrobat) |
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F:
Hexazinone, 11 pages. (Word,
Acrobat) |
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G:
Imazapic, 8 pages. (Word,
Acrobat) |
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H:
Imazapyr, 7 pages. (Word,
Acrobat) |
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I:
Picloram, 10 pages. (Word,
Acrobat) |
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J:
Sethoxydim, 6 pages. (Word,
Acrobat) |
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K:
Triclopyr, 8 pages. (Word,
Acrobat) |
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Appendices |
Appendix
1 - PVC applicator, 2 pages. (Word,
Acrobat) |
Appendix
2 - Spot-burning, 4 pages. (Word,
Acrobat) |
Appendix
3 - How to read a pesticide label, 4 pages. (Word,
Acrobat) |
Appendix
4 - How pesticides are regulated in the U.S., 2 pages. (Word,
Acrobat) |
Appendix
5 - List of Personal Contacts, 1 page. (Word,
Acrobat) |
Appendix
6 - List of state regulatory agencies, 6 pages. (Word,
Acrobat) |
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Water
Hyacinth:
Illegal Aquatic Plants of South Carolina
(Free,
PDF file ):
South Carolina Dept. of Natural Resources, Aquatic Nuisance Species
Program
Link http://water3.dnr.state.sc.us/dnr/water/envaff/aquatic/img/hyacinth.pdf
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Help Prevent the Spread of
Aquatic Plants and Animals (IL-IN-SG-98-1,
Free):
Illinois-Indiana Sea Grant
Link http://www.iiseagrant.org/publication/br.htm
Fact
sheet describes how exotic aquatic species are spread by boaters.
Provides easy steps boaters can take to prevent spread of exotics
when transporting watercraft. 4p. |
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Aquatic Exotic Animals & Plants
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