Seed Cotton Module Storage and Handling

Who Should Have Seed Cotton Storage Capability?

If you answer Yes to any of the following questions, you should consider using the module system for seed cotton storage and handling.

1. Do you harvest more than 600 bales of cotton annually?
2. Do you operate at least two 2-row harvesters?
3. Does the gin where you gin serve more than 2 1/2 times its rated hourly capacity in picking capacity during peak harvest period or in high-yielding years? (Figure each 2-row picker after 1975 at 4 bales per hour and each 4-row at 6 bales per hour. Figure each 2-row machine manufactured before 1975 at 2 1/2 bales per hour.)
4. Could you increase your picking efficiency by 10 percent with extra seed cotton handling capacity?
5. Have you ever had to stop harvesting more than one day per season because trailers were unavailable?
6. Does the gin where you gin provide a module builder or hauling service?
7. Do you plan to expand your cotton operation in acreage or increase picker capacity in the near future?
8. Do you haul a major portion of your crop more than 20 miles one-way to the gin? If so, you may want to consider a pallet-module handling system.
9. Are bridges and roads suitable for hauling modules? You could be dealing with a 50,000-pound gross load.
10. Will your gin be ginning larger volumes of cotton because of increased acreage or because other gins in the area are closing?

Sizing A System For Your Needs

Excessive picker capacity per module builder and more than 12 bales per module cost you in lost efficiency and poorly constructed modules. Poorly compacted modules may fall apart during hauling, especially with repeated loadings. Improperly rounded and compacted modules pond water and cause rotting if water enters the module.

Transportation Alternatives

Pallet systems are suited to small, annual volumes when storage is needed to satisfy a few larger growers or where haul distances exceed 25 miles (one-way haul). Self-loading trucks best serve gins with more than 6,000 bales per year handled in modules and shorter haul distances (8-12 miles being an average working radius).

For these reasons, gins have invested in self-loading module trucks and haul modules as a free service in return for the opportunity to gin customers' moduled cotton. Seed cotton losses from palletless cotton-handling systems are no more than with pallet systems -- provided modules are well constructed on dry, level areas and a trained operator is moving the module.

Table 1. Total cost per bale seed cotton handling system for 5-year payback.

* 1,200 bales/year/module builder

Field Operations Required For Module Builders

Seed cotton that is below 12 percent moisture stores without deterioration of lint or seed. During harvest, check seed cotton moistures with a portable moisture meter. Bite the seed; if it cracks, the seed cotton is safe for storing in modules.

Site Selection and Preparations -- Select a site with the following guidelines:

• Well-drained turnrow or field road.
• Free of gravel, stalks, and debris.
• Smooth and near-constant grade.
• The module aligned north to south, if possible, to promote drying on both sides.
• Accessible in wet weather. (If not, plan to move the module immediately after building.)
• Away from highly traveled roads and other possible sources of fire.
• Clear of overhead obstructions such as utility lines.

Module Building -- A minimum of three men is required to operate the module builder, to clean picker heads, and to tarp modules. Priority of jobs should be in that order. The module-builder operator should not have any other responsibilities.

Schedule harvesters so that only one dumps at a time. The first and second picker dumps should be made in each end of the module builder. The third dump should be made near the middle of the builder and leveling and tramping begun immediately and continued until the module is completed. The tighter the module is compacted, the better it sheds rainfall on the sides and the less seed cotton is lost during storage, loading, and hauling. Additional dumps should be made where cotton is needed in the module to keep the module level-to-rounded in the center. Where pickers are capable of dumping a partial basket, use the picker to spread cotton the length of the builder. This allows the picker to complete unloading faster, spills less cotton over the side of the module builder, and it is easier for the module-builder operator to level and tamp the module, especially when topping off the module.

Give the module-builder operator the authority to call in pickers when a partial basket is needed to top off a module and to direct the picker operator where to dump in the module.

Carefully tamp the ends of the module to prevent seed cotton from falling during storage, loading, and hauling. Round the top of the module, and fill in depressions that may cause ponding of water.

Boll Buggies -- Use boll buggies and trailers to increase picker efficiency. Pickers should not have to wait until a module is topped off and the builder moved to a new location to dump. Likewise, pickers should not have to go more than 200 yards to the module builder. Boll buggies can permit dumping pickers on the far end of the field or allow a module to be on higher ground away from the immediate turnrow, without excessive picker travel. Trailers can be used to handle overflow cotton while a module is being completed.

Covering Modules -- Immediately after making the modules, cover them with a high-quality cotton (12 oz/yard before treatment) or a synthetic tarp.

Cotton tarps permit moisture vapor to pass through the tarp and, therefore, are less likely to have condensation form due to the daily heating and cooling of the cotton's surface. These tarps should be tied with some "give" in the ties so that shrinkage does not damage the tarp. Cotton tarp's finished dimensions should be six feet wider than the module builder and eight feet longer to cover adequately the top edges of the module and to allow for shrinkage. If a module is properly packed, the sides shed water, and the module requires no additional protection. Cotton tarps should be checked for tear strength and leakage with a simple bucket (ponding) test, especially after one or more use. Lay the tarp over a bucket (about 1-foot diameter), from a depression and fill with water. After an hour, if the tarp passes more than one drop per minute, the tarp should be rewater-proofed before using.

Synthetic tarps are lighter, less costly, and generally more durable than are cotton tarps. Economics alone justifies the use of synthetic tarps. However, since they permit less moisture vapor to pass through, some precautions must be taken with synthetic tarps to prevent seed cotton quality losses from occurring. When ordering synthetic tarps, specify adequate ultraviolet light inhibitor to protect the tarp for two or more seasons or 180 days of exposure. Inspect tarps during use and before reuse for deterioration. Specks of tarp material flying off or on the surface of a module are good indications that the ultraviolet light inhibitor was not adequate.

By using form-fitted tarps or loosely tying synthetic tarps, trapped moisture can be expelled with normal wind movement up the side of the module and under the tarp. To maximize this effect, orient modules with the length perpendicular to the prevailing wind direction. Insuring that cotton is dry enough for storage before moduling eliminates much of the condensation potential under synthetic tarps. Inspect tarps before the morning sun evaporates condensation. If condensation is occurring, water may run down the bottom face of the tarp or cotton is damp to the touch.

Tying Down Tarps -- Tying tarps is accomplished in several ways. A good cotton twine (500-pound-minimum-breaking strength) is the preferred tie-down material to avoid lint contamination. The most economical tie-down is a 1/4-inch or 3/8-inch braided-nylon-strap material. Take extreme care to insure that no synthetic strapping material is allowed to be mixed with the seed cotton, either in the field or at the gin.

The most widely used method of tying down tarps is to lay twine or strapping across the width of the new module site (at two- or three-foot intervals) after the builder is moved to the new location, but before the builder is set down in the operating position. Materials should be long enough to reach up each side of the module and to allow a length for tying to the tarp. Do not cut the material when tying the tarp after the module is completed; this increases the chances of lint contamination with a synthetic material.

Another tying method is to use steel pins 18-24 inches long with an eye that can be inserted into the module about 4 feet from the top of the module. Use rubber straps or tie-down material from the tarp's grommets to the pin.

Form-fitting tarps are designed with a drawstring or require no tie-down since they grip the ends of the module and need to "flap" to expel trapped moisture.

Module Monitoring For Quality

Monitor temperatures daily for five days after the module is built. Heating usually occurs within three days after harvest, unless the module becomes wet from ponded water (top or bottom). Gin immediately if seed cotton exceeds 120 °F at any one of a minimum of 6 temperature probes made with a 3-foot-long stem thermometer 3 feet above the ground level (at random) around the module. Gin immediately if seed cotton temperature increases more than 20 °F above the air temperature when the module was made. If any water ponds on the tarp, regardless of tarp material, drain off and gin as soon as possible.

If temperatures have not approached or exceeded 120 °F or 30 °F rise (whichever is lower) in the first five days, modules can be monitored on an every-other-day schedule for one week. For each week stored, extend the monitoring interval one day until you monitor on a weekly schedule (after six weeks).

A visual inspection should be made weekly and following rains, to detect damaged and blown tarps, theft or vandalism, and ponding water.

Recordkeeping

Any records or numbers assigned to modules should be as permanent as possible. Permanent ink, such as in nursery marker pens, should be used on cards attached to modules. Plastic zip lock bags can be used to help protect cards, but it is difficult to get a leakproof bag. Number each module successively as modules are built so you can identify the module with permanent records. Numbered tarps with a gin or producer name are ideal for identifying the tarp but are of little value if the tarp is stolen or destroyed. The modules may be marked with a noncontaminating spray paint product, "Brand-A-Bale," developed for marking cotton modules.

By Herbert Willcutt, Extension Agricultural Engineer, and William H. McCarty, Extension Agronomist, Cotton

Mississippi State University does not discriminate on the basis of race, color, religion, national origin, sex, age, disability, or veteran status.

Publication 1561
Extension Service of Mississippi State University, cooperating with U.S. Department of Agriculture. Published in furtherance of Acts of Congress, May 8 and June 30, 1914. Ronald A. Brown, Director

Copyright by Mississippi State University. All rights reserved.

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