Unwanted Vegetation

Aquatic plant life is desirable in aquatic habitats. One-celled aquatic plants (algae) are the basis of the food chain and supply oxygen to the aquatic system. Larger plants offer shelter and breeding habitat for many aquatic organisms. A balance between plants and other aquatic life is therefore beneficial.

When aquatic plants begin to flourish and affect human activities negatively, these plants are referred to as "weeds." The "weed" determination may be based on the location in which the plants are growing such as boating lanes or around boat docks. Problems also arise when the aquatic plants interfere with the intended use of the body of water such as swimming, skiing or fishing.

Most problems are caused by introducing exotic species which have no natural controls to keep growth in check. Without these natural control mechanisms, the plants quickly replace native vegetation. Exotic species that have become problems are giant salvinia, common salvinia, water hyacinth, alligatorweed and hydrilla.

Factors Affecting Control

Environmentally sound and cost-effective management decisions should be the basis of any aquatic weed control program. Plant identification is critical because control methods are usually species specific. All control measures will affect the environment, so it is important to consider the intended use of the water body. Physical constraints such as shallow water or obstacles can impair herbicide applications. Water quality variables such as total alkalinity or the possibility of dissolved oxygen depletions are important considerations. Potential impacts on fish and wildlife populations must also be considered.

Pond Construction

Prevention is the easiest and most economical method to control aquatic weeds. Proper site selection is the first step in preventing aquatic weed problems. Sites should be selected that minimize erosion, nutrient enrichment from runoff and high water flows through the pond. Avoid using a flowing stream as a water source because the continuous flushing creates clear water and causes low contact times for herbicides and fertilizers. Maintain proper watershed-to-pond ratios. Limit livestock usage in the watershed to lessen erosion and levee destruction. Pond banks should be as steep as possible without causing excessive sloughing. Inside levee slopes should drop 1 foot for every 3 feet the slope extends into the water. Avoid areas shallower than 3 feet deep to minimize excessive weed growth. Encourage grass species along banks such as Bermuda and rye.

Preventive Fertilization

Fertilization provides nutrients for algal growth, which reduces light penetration below the level required for submerged plant growth. Once fertilization has begun, you must continue the program to prevent adverse effects on fish populations. Do not start a fertilization program until the current weed infestation is controlled. The plants you are trying to control will use the nutrients and increase their growth. Liquid fertilizers are preferred because they give faster results.


Drawdown is limited to lakes and ponds with adequate water control structures and a reliable source of water for refilling the pond. Drawdowns are usually conducted during winter to expose plants to drying and freezing. The advantages include low cost as well as oxidation and consolidation of sediment. Drawdowns also increase options for chemical control because some chemicals are more effective when applied to dry water bottoms. One disadvantage of drawdowns is that they may reduce desirable species and allow tolerant species to spread further. There may also be some loss of recreational benefits such as duck hunting and spring fishing.

Mechanical Control

Physical harvesting by hand or equipment can be effective at removing small populations of nuisance weeds such as duckweed, cattail and water hyacinth. This can be accomplished with various methods such as dip nets, sickles or blades, and by placing barriers across incoming streams to restrict floating plants. The main advantages to mechanical control are low cost and low environmental impact.

Biological Control

There have been many attempts to control aquatic plants with biological control methods. These include pathogens, insects and herbivorous fish. For the average pond owner, the use of herbivorous fish like triploid grass carp is the only biological control method available. Triploid grass carp are functionally sterile, meaning they cannot reproduce in ponds. The Louisiana Department of Wildlife and Fisheries has developed a permit to allow farm pond owners to use these fish to control vegetation.

The number of grass carp that should be stocked depends on the type of weed, condition of the ponds and severity of the weed problem. Triploid grass carp prefer submerged plants, but some emergent species are also controlled. Some recommendations for stocking rates are given in the next column.

Recommended Stocking Rates for Triploid Grass Carp

Weed Evaluation
Number of Fish to Stock per Acre

New pond or very slight weed problem

Moderate weed problem (10 to 20 percent coverage)
10 to 15

Severe weed problem
5 to 20 or more


Chemical Control

About 200 herbicides are registered in the United States, but only 10 are labeled for aquatic sites. These chemicals can control aquatic weeds effectively. However, correct weed identification and matching the proper herbicide to the particular weed problem are extremely important.

Aquatic plants which are usually considered problems are divided into four groups: algae, floating, submersed and immersed weeds. Algae are small, usually microscopic plants lacking leaves, roots and stems. These plants may be made up of only one cell, an aggregate of cells called a colony, or a chain of cells called a filament. Algae may grow freely suspended in the water (plankton), floating at the water surface (pond scum) or attached or unattached on the bottom. Free-floating weeds such as duckweed and water hyacinth have leaves and stems above the surface and roots that suspend in the water below.

Submersed weeds are usually rooted at the bottom and often extend to the water surface. Common weeds in this group are hydrilla, coontail and watermilfoil. Emersed vegetation is also a problem in ponds and lakes. Growth usually occurs on or near shore and in shallow water areas. Plants are rooted in the bottom, and their leaves and/or stems extend above the water surface. Common emersed weeds are smartweed, alligatorweed and cattail.

When considering herbicides for control of aquatic weed problems, remember two important points. First, the label on the herbicide container provides specific information on the proper use of the chemical. Protect yourself and others by reading and abiding by directions and warnings on the product label.

A second consideration is that as dead aquatic plants decay, oxygen in the surrounding water is used in the process. If large quantities of plants are killed with one treatment, dissolved oxygen in the water may be reduced to the point that fish and other aquatic organisms die. Therefore, it is usually desirable to treat only a portion of a weed problem at a time. This allows the body of water to recover lost oxygen before subsequent treatments. The possibility of low oxygen becomes more serious as water temperatures rise in late summer. If possible, weed problems should be dealt with when water temperatures are between 70 and 80 degrees F.

There are several methods for applying herbicides. Some herbicides can be applied directly from the container. Handheld or backpack sprayers are used for spraying emersed vegetation around the shoreline. Boat-mounted tank sprayers can be used for either surface spray or subsurface injection. Hand-operated or mechanical spreaders are used for dispensing granular material. Granular material can also be dissolved by towing it in a bag behind a boat.

When considering chemical control, check with the parish Cooperative Extension Service office or a fisheries biologist for plant identification and current herbicide recommendations. Additional information on aquatic weed control and related topics is available from your local Extension office. Request these publications: Handbook for Common Calculations in Finfish Aquaculture, Pub. 8903; Aquatic Weed Management: Herbicides, Pub. 2398; Aquatic Weed Management: Control Methods, Pub. 2410.

Source: Management of Recreational and Farm Ponds in Louisiana," LSU AgCenter, Pub. 2573, 11/03 Rev."  

Stocking Public Waters

Stocking Public Waters
Stocking Public Waters
Stocking Public Waters
Stocking Public Waters

How to Stock Ponds

Stocking Procedures

Once the decision has been made as to what to stock, it is important to follow the proper procedures to maximize the health and survival of the fingerlings purchased. If survival of one or another type of fish being stocked is low, actual numbers will differ greatly from the recommended rates, and pond balance may be difficult to establish or maintain. In some instances, high mortality shortly after stocking may go unnoticed. For this reason, every effort must be made to minimize stress during transport and stocking.

Acclimation Procedures

Fingerlings for stocking are generally transported in hauling tanks with aeration or in sealed bags with oxygen. Upon arrival, gradually replace water in hauling tanks with water from the pond to be stocked. This can be done with a small pump or with buckets. Adjust temperature gradually, with no more than a 7-8 degree F increase or a 5 degree F decrease per half hour. Continue aeration during this process. When temperatures have been adjusted, transfer fish to the pond as gently as possible, with minimal handling.

If fingerlings arrive in sealed plastic bags, float the bags in a shady area for 30 minutes, then open them and immediately release the fish. Normally, pond water should not be gradually mixed with shipping water in bags. Carbon dioxide and ammonia build up in shipping bags during transport. Since these compounds cannot dissipate into the atmosphere, dissolved carbon dioxide reaches very high levels, lowering the pH of the shipping water. Opening the bags allows the carbon dioxide to escape rapidly, and aerating or splashing accelerates this process. The pH rises drastically, and any ammonia present rapidly converts to the toxic form. This chain of events will kill fry and small fingerlings quickly.

This problem is less serious when transport times are short and when fish have not been fed for several days. Gradual mixing of pond water with transport water in bags (after temperature adjustment) is usually desirable only when moving young fish from hard water to moderately or very soft water. When attempting this procedure, monitor the fish closely for signs of stress, and introduce them directly into the pond if they begin to appear weak or disoriented. 

Alexander State Forest

Louisiana Department of Wildlife and Fisheries
7,955 Acres
(318) 371-3050

Alexander Forest Wildlife Management Area is located in south central Rapides Parish about ten miles south of Alexandria, off U.S. Highway 167, and one mile east of Woodworth.
The Louisiana Department of Agriculture, Office of Forestry is the owner of this 7,955 acre tract which is managed as commercial forest with an emphasis on experimental forestry techniques. Indian Creek Lake, a 2,600 acre reservoir, is located on the area along with a 300 acre recreation and camping area.
The forest overstory is predominantly loblolly pine with scattered stands of longleaf and slash pines. Much of the timber is managed as pine plantations. However, creek drainages have been maintained in hardwoods. In addition red oak, blackgum, sweetgum, hackberry, beech, water and willow oaks are widely scattered over the forest.
Game species available for hunting include deer, squirrel, rabbit, quail and waterfowl. The featured species on the area is white-tailed deer. Herd density is good with antler quality and body weights typical of piney woods sites. Hunter success during the either-sex muzzleloader hunts is generally above average.
An education center is owned and operated by the Department on a 17 acre site within the WMA. The center is used for a variety of educational programs. Two shooting ranges are located on the grounds. The 100 yard rifle and pistol range and a shotgun range are used in education programs and also available to the public during specified times. Information on range hours and fees is available at (318) 484-2212.
Louisiana Wildlife and Fisheries operates two fish hatcheries adjacent to the WMA. These hatcheries are the primary source of fish for the statewide stocking program. Booker Fowler hatchery has a visitor center and offers hatchery group tours by appointment. For hatchery information call (318) 748-6914.
Two boat ramps are located on Indian Creek Lake. Sportfishing is the major activity on the lake. Water-skiing and swimming are also popular recreational uses. Camping facilities are operated and maintained by the Office of Forestry. Trailer and tent accommodations are available with electricity, water, bath houses and swimming areas. A fee is charged for the use of these facilities. For camping information telephone the Indian Creek Recreation Area at (318) 487-5058.
Additional information may be obtained from the Louisiana Department of Wildlife and Fisheries, 1995 Shreveport Highway, Pineville, LA 71360.

Invasive Species/Prohibited Exotics

The Department of Wildlife and Fisheries and Chef Philippe Parola, in an effort to produce a demand for two species of Asian carp, the silver and bighead carp (Hypophthalmichthys molitrix and H. nobilis), are launching the "Silverfin Promotion." Both species of carp are exotic to U.S....
The Louisiana Department of Wildlife and Fisheries has received reports and actual specimens of GIANT TIGER PRAWNS or Penaeus monodon, a non-native species of shrimp in Vermilion and Barataria Bays. This species of shrimp is native to the Western Pacific. If a population were established in our...
Snakeheads are native to Asia.  Their names comes from the enlarged scales that cover their heads.  Snakes are obligate air breathers.  Unlike most fish, they must obtain oxygen directly from the air rather than water.  They can live up to three days outside of water.  They...

Aquatic Species

Albino channel catfish (Genetic variation of Channel catfish)
Insects, crayfish, fish
Alligator gar
7-9.5 feet
150-300 pounds
Large rivers along the Gulf Coast
American eel
54 inches
16 pounds
Newfoundland, Atlantic and Gulf coasts, Caribbean to Brazil
Bigmouth buffalo
40 inches
50 pounds
Zooplankton, insects, algae
Mississippi River drainage
Black buffalo
40 inches
50 pounds
Zooplankton, insects, algae
Mississippi River drainage, south of Minnesota and High Plains
Black bullhead
12 inches
2 pounds
Insects, crustaceans
Central United States
Black crappie
16 inches
5 pounds
Small fish
South Canada, Great Lakes, southern United States to east Texas
Blue catfish
50 inches
60 pounds
Detrius insects, mollusks, crayfish, fish
Mississppi River Basin, Gulf Coast drainages
48 inches
45 pounds
East coast of United States
16 inches
4 pounds
Small fish, invertebrates
Great Lakes to southern Florida, Gulf states to Arkansas
3 feet
20 pounds
Fish and vertebrates
Southern Canada to Florida
Brown bullhead
20 inches
5 pounds
Crustaceans, insects, worms, algae, mollusks, fish
Eastern United States
Chain pickerel
31 inches
9 pounds
Canada to Florida Atlantic Coast, east Texas
Channel catfish
50 inches
60 pounds
Insects, crayfish, fish
Widely distributed throughout the United States
Common carp
48 inches
80 pounds
Widespread throughout the United States
Creek chubsucker
14 inches
2 pounds
Small crustaceans, insects, algae
Widely distributed in United States from Gulf Coast to Great Lakes
Flathead catfish
60 inches
90 pounds
Insect larvae, crustaceans, and fish
Rio Grande, Pecos, and Gila watersheds, introduced into many western streams
7.5 inches
.5 pounds
Insects, crustaceans and small fish
Coastal Plain from south Maryland to Florida and Gulf to lower Mississippi
Freshwater drum
35 inches
54 pounds
Canada, Great Lakes, Mississippi drainage to Alabama, east Mexico.
Golden shiner
12 inches
1.5 pounds
Newfoundland to south of Everglades, Rio Grande, edge of Great Plaints
Green sunfish
12 inches
2.5 pounds
Aquatic insects, insects and small fish
Tributaries of Mississippi River from Canada to the Gulf of Mexico
Largemouth bass
38 inches
20 pounds
Every state, originally from Great Lakes and from Rio Grande to Florida
Longear sunfish
10 inches
2 pounds
Insects, small invertebrates
Great Lakes to upper St. Lawrence River, west Florida, Texas
Longnose gar
40 inches
15 pounds
Eastern half of United States along major river ways
2.6 inches
Surface insects and larvae, small crustaceans, algae, and its own young
Mid Atlantic region, Delaware to Florida and west to Alabama
Orange spotted sunfish
3-5 inches
.25 pounds
Small crayfish and aquatic insects
Eastern North Dakota, South Minnesota, East Texas, Louisiana, Ohio Valley and Central High Plains
60 inches
160 pounds
Mississippi and Missouri River drainages
Pygmy sunfish
1.3 inches
Several ounces
Micro crustaceans and aquatic insects
Coastal plains of the Carolinas
Red drum
61 inches
90 pounds
Crustaceans and mollusks
New York to Texas coast
Redbreast sunfish
10 inches
2 pounds
Aquatic crustaceans and invertebrates
East of Allegheny Mountains from New Brunswick to Florida
Redear sunfish
15 inches
4 pounds
Small mollusks
Mid Atlantic states to Central Florida, Gulf of Mexico
Redfin pickerel
14 inches
2 pounds
Small fish and aquatic insects
Canada throughout coastal drainage, Coastal plains from Maryland to Georgia
River Carpsucker
24 inches
10 pounds
Worms, crustaceans and algae
Great Plains from northern Mexico to Montana and Minnesota
18 inches
4 pounds
Fish and crayfish
Central North America
Shortnose gar
2 feet
3.5 pounds
Fish, crayfish, insects
Missouri, Mississippi, Ohio River drainages
Skipjack herring
21 inches
3.5 pounds
Small fish
Mississippi, Ohio, Missouri Rivers
Smallmouth buffalo
3 feet
51 pounds
Small crustaceans, aquatic insects
Below Great Lakes, mid-central states, south Texas
Spotted gar
3 feet
28 pounds
Coastal plains of Texas and Louisiana, lowlands of Oklahoma, Missour
Spotted seatrout
36 inches
16 pounds
Shrimp and fish
New York to Florida and throughout the Gulf of Mexico
Spotted sucker
19 inches
4.5 pounds
Aquatic insects, algae
Lower Great Lakes and Gulf to Atlantic. Coast Texas to North Carolina drainages
Striped bass
50 inches
70 pounds
Gulf of St. Lawrence to north Florida, Gulf of Mexico to Louisiana
12 inches
2 pounds
Minnows, insects
Primarily southern United States
White bass
18 inches
3-4 pounds
Minnows and small invertebrates
Great Lakes, eastern central United States, Gulf of Mexico to Missouri River
White crappie
16 inches
5 pounds
Small fish
Great Lakes, Texas, Louisiana, east coast
Yellow bullhead
12 inches
2 pounds
Detrius plant matter, crayfish, insects, mollusks, fish
Eastern half of United States

Louisiana Oyster Task Force to Meet August 27

Release Date: 08/23/2010


The Louisiana Oyster Task Force is scheduled to meet at 1 p.m. on Friday, August 27 at the UNO Advanced Technology Center located at 2021 Lakeshore Drive, Suite 210 in New Orleans.

The agenda is as follows:

I.                   Roll Call

II.                Approval of July 27, 2010 Minutes

III.             Treasury Report

                    A. Oyster Tag Sales

                    B. LOTF Financial Report & Budget for 2010-2011

IV.       Committee Reports

A.  Public and Private Oyster Grounds Committee

B.  Enforcement

C.  Legislative

D.  Research

E.  Coastal Restoration ? Re: Fresh Water Diversions ? Dan Coulon

F.  Marketing ? Re:  Budget for 2010-2011 ? Dana Brocato

 V.      Old Business

A.   Oyster Season Schedule

B.   BP Oil Spill Update

         1.  Claims Process

         2.  Oyster Lease Damages

VI.                   New Business

A.   RTI Oyster Study for ISSC ? Catherine Viator, Research Triangle Institute

B.   DHH Oyster Relay Rules, Suggested Changes ? David Guilbeau

C.   NOAA Biological Study Presentation - Heather Finley

D.   Oyster Lease Survey Changes - Raymond Impastato

E.   Public Seed Ground Rehabilitation

F.    Washington Mardi Gras ? Al Sunseri

G.   Taxes-concerning BP payments - Dan Coulon

VII.        Set Next Meeting

VIII.      Adjourn

For additional information, please contact Laura Deslatte at (225) 610-2363


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