Procedures for harvesting and handling vary considerably with vine crops and in some cases with the intended market. Growers must ensure adequate supervision and training of crews to prevent loss from improper harvesting and handling techniques.
Watermelons reach harvest maturity 5 to 6 weeks after pollination, depending upon variety and season. Varieties can differ in maturity characteristics. An experienced person can identify a ripe melon by glancing at the glossy rind surface. Other indications of ripeness include a change in the color of the ground spot from white to light yellow; a change of tendrils nearest the fruit from green to brown and dry; stripes at blossom end become less defined; and thumping the fruit. When thumping, a metallic ringing sound indicates immaturity, and a more muffled or dull sound indicates maturity or over-maturity. Thumping is a reliable method to detect over-maturity in round-shaped melons. The best method is to cut open a few melons in various parts of the field. Harvesting and marketing green or over-ripe melons lessens the demand by consumers. Sugar content does not increase after harvest; however, red color will continue to develop after a slightly immature melon is picked.
Melons should be cut from the vine leaving a long stem rather than pulled, twisted, or broken off to reduce chances of decay. Following harvest, keep melons out of the sun; temperatures above 90°F can cause flesh breakdown, and do not place melons with bottom sides turned-up as the ground spot can easily sunscald. Prevent bruising the fruit by handling them carefully at all times and never standing them on end, because this can cause the flesh to separate from the rind. When hauling melons from the field, use straw or paper padded vehicles to reduce bruising, punctures, and rind abrasion. Do not allow field hands to ride on top of the load.
After harvest, load melons directly into trucks for shipment to market or haul them to a central grading station for reloading and shipment. Melons are usually graded and sized during the loading operation. Traditionally, melons have been hauled in bulk in trucks. The use of containers has gained popularity because they are more efficient in unloading, and injuries related to rough handling during loading and unloading are reduced. Bulk bins made of corrugated fiberboard and holding around 1,000 pounds as well as cartons holding 3 to 5 melons are used. Fruit sizes for packing include small (<18 pounds), medium (18-25 pounds), and large (>25 pounds).
Harvest from early planting usually begins in late June in southern Oklahoma. Harvesting requires a great deal of hand labor. Melons are usually picked every other day for the first 2 or 3 picking days and every day for the next 20 to 25 days. Length of harvest depends on the condition of the vines, number of melons, season of year, and the market.
When properly matured for shipping (market maturity), cantaloupes should be "half-slip," firm, well netted, and not deeply colored. At "half-slip" the abscission layer between the stem and fruit is half formed and will allow the remaining half to separate from the melon with a slight pull. A cantaloupe that has not reached "half-slip" is not fully developed and has not obtained maximum sweetness, flavor, and aroma. Eating maturity follows about 3 days after "half-slip" harvest when the cantaloupe is held at room temperature. Best flavor is attained if melons are held near 70°F for final ripening, then chilled for serving. Cantaloupes are either hand picked into picking bags or buckets that are dumped into field trailers, or they are picked and placed directly into a nearby hauling vehicle.
Honeydew, casaba, and crenshaw melons are cut from the vines at market maturity. Casaba and crenshaw should have developed some yellow skin color and a slight softness on the blossom end when firm pressure is applied with the thumb. Honeydew melons are at market maturity when 1) normal size has been obtained, 2) ground spot is white to slightly greenish, and 3) a waxy skin coating begins to develop.
At the packing location melons are graded, sorted, and packed into crates or cartons according to size for the shipping market. For short distance shipping or local markets, melons are often hauled in bulk. Several sizes are packed: 12, 15, 18, or 23 melons in a 1/2 carton or crate weighing 35 to 40 pounds. The smaller the number of melons that fit into the crate, the larger the size of those melons. The size 15s are generally the most desirable.
Until recently, few Oklahoma cantaloupes were cooled before shipment. However, cooling prior to shipment improves marketability and increases the time for melons to reach full ripeness, which extends shelf life. Most buyers are demanding that melons be cooled prior to shipment.
Summer squash are harvested over several weeks and must be harvested every other day during the peak production season. They are harvested as soon as fruit is of edible size, but before the skin begins to harden. Varieties with long fruits are harvested measuring less than 3 inches in diameter and up to 6 to 8 inches long. Scallop squash are harvested when they are 3 to 4 inches in diameter. Summer squash are very tender and must be handled with great care to prevent mechanical damage. Defective and large summer squash fruits should not be allowed to remain on the plant as this reduces additional fruit set. Summer squash should be cooled before shipment to maintain quality, and may be waxed or oiled to slow water loss and reduce abrasions.
Winter squash and pumpkin are harvested when mature and are normally harvested
in one or two pickings. The skin is hard and resists denting by thumbnail pressure
when mature. Winter squash and pumpkin can remain in the field through a light,
vine-killing frost but should not remain in the field during a hard frost. When
harvesting, cut the stem leaving a stub attached
to the fruit. Fruit should be handled carefully to avoid breaking the skin and
bruising. Summer squash is usually packed in 1/2 or 5/9
bushel crates or cartons weighing 21 pounds or in 1 1/9
bushel crates weighing 42 to 45 pounds. Winter squash are commonly packed in
1 1/2 bushel crates weighing 40 to 45 pounds.
In normal seasons, the first picking can be made 45 to 60 days after planting. Generally, cucumbers are harvested every 2 or 3 days, but under ideal growing conditions, daily harvest may be needed to harvest a high percentage of fancy grade fruit. When picking, do not pull the cucumber from the vine. This may tear the fruit and damage the vine. When picked properly, the stem is pushed off the fruit with the thumb. Cucumbers must be fresh and crisp when received by consumers. The market desires a uniformly dark green cucumber that is well formed, straight, and of medium size. This requires frequent picking and careful handling and grading. Allowing fruit to become too large on the vine will reduce quality and yield of the crop. Slicing cucumbers are usually waxed after washing. This adds to the cost of production, but is usually demanded by buyers, as it improves appearance and is effective in preventing shrinkage and loss of freshness during storage, shipping, and marketing. Cucumbers are usually packed in cartons or wire-bound crates weighing 50 to 55 pounds.
Vine crops, except some winter melons, squash, and pumpkins, are not suited for storage. Production and marketing must be coordinated to ensure that storage is limited to short-term holding enroute to market. Refrigerated holding facilities must be available for short-term use during harvest season. The optimum holding environment varies with each crop and the stage of maturity at which the crop was harvested.
If necessary, watermelons will keep for 2 to 3 weeks at temperatures between 52 to 60°F. Relative humidity should be 85 to 90%; higher humidity may promote stem-end rot. Watermelons are not adapted to long storage. They are subject to chilling injury at or below 50°F and lose flavor and color. Decay, mainly black rot (Didymella), can be expected on watermelons previously stored at 50°F and lower. At temperatures above 60°F, watermelons are subject to decay. Holding watermelons for up to a week at room temperature can improve flavor and color. However, after several weeks at room temperature they have very poor flavor and texture (loss of crispness). Watermelons are sensitive to ethylene (causes flesh breakdown and rind yellowing) and should not be stored or shipped with products that emit ethylene, such as ripe cantaloupes, apples, pears, tomatoes, and bananas.
Cantaloupes are highly perishable. When harvested, handled, and held under optimum conditions, they will be of only fair quality 2 weeks after harvest. If 1/2 to 1/4 slip cantaloupes are held or stored, they should be refrigerated at 35 to 45°F. Winter melons (honeydew, casaba, and crenshaw) will develop chilling injury if held or stored below 45°F, expressed as pitting, red-tan discoloration, off flavor, and failure to ripen. Honeydew melons absorb odor and should not be stored with apples, potatoes, onions, or cantaloupes. Cantaloupes and winter melons should have adequate ventilation because melons in tightly packed cold rooms can develop carbon dioxide injury (browning of sutures and rind).
Summer squash are perishable and should not be stored. They can be held for 1 week prior to marketing at 45 to 50°F and 90 to 95% relative humidity. Green types, such as zucchini, are sensitive to yellowing if held above 50°F or exposed to ethylene. Winter squash and pumpkin can be stored for later marketing. If stored, they should be cured to harden the shell, ensure maturity, and to heal any cuts and scratches. To cure, winter squash and pumpkin are held for 10 days at 80 to 85°F, and 80% relative humidity. Acorn squash can be stored up to 2 months and butternut squash and pumpkin for 2 to 3 months.
Cucumbers can be held up to 14 days at 50°F and 90 to 95% relative humidity. The fruits are very susceptible to shriveling, so relative humidity must be kept high. Cucumbers turn yellow if held above 50°F and develop chilling injury below 50°F, expressed as pitting and water soaked lesions. Do not store with fruits that produce ethylene, such as ripe cantaloupes, apples, pears, and bananas.
A pesticide applicator, employees, and customers may be exposed daily to many pesticides. Consider the pesticide's total effect on the crop and following crop(s), not just the control of the target pest. Consider such possible side effects as phytotoxicity, drift damage, and crop rotations when developing a pest management system. Producers' health and business depend on knowledge and care in application.
The greatest hazard to the target plant is an adverse or "phytotoxic" reaction to the pesticide applied. If phytotoxicity is severe, the plant may die. Symptoms of phytotoxicity include:
Phytotoxicity often mimics such things as insect damage, plant disease, and response to poor growing conditions such as insufficient moisture and improper fertilization.
The following items are especially relevant to the phytotoxicity problem:
The cause of phytotoxicity may be easy to determine or it may be subtle and hidden.
· High air temperature during and immediately after pesticide application Several pesticide labels warn of potential injury to plants if applied at or above certain temperatures.
· Excessive rates of pesticide application Overdosing generally does not give any better control of the target pest and can injure the plant.
· Too little water Insufficient dilution of the pesticide when mixing will result in more concentrated spray. Plants under moisture stress may be more sensitive to chemical injury.
· Uneven distribution of pesticide Inadequate mixing of pesticides in the spray tank may result in uneven distribution of the chemical. Wettable powders in particular need agitation to keep them uniformly suspended in water.
· Formulation Certain formulations may cause injury more than other types. Emulsifiable concentrates are more likely to cause injury than wettable powder. The solvents in them may allow the chemical to come into direct contact with the plant tissue by dissolving the waxy protective layer on the leaves.
· Mixing liquids or emulsifiable concentrates with wettable powders
· Variety and species differencesSome varieties or types of cucurbits may be more sensitive to certain pesticides than others. This will be stated on the label.
· Growing conditionsWeak plants in shallow soils, wet spots, or under other types of stress are more sensitive to chemical injury. Young, tender, fast growing plants with areas of new growth tend to be more susceptible to injury.
Finally, take special care to avoid injury to cucurbits when using herbicides. Some herbicides leave residues in spray tanks that injure desirable plants. Use separate sprayers for herbicides and other pesticides to eliminate this source of injury.
The proximity of different plants with varying planting or harvest dates requires applicators to be especially aware of drift problems.
Two types of drift are associated with pesticides. The most common is spray droplets. Spray pressure, nozzle size, wind velocity, and pesticide formulations directly affect spray droplets. Smaller droplets drift further than larger droplets. Increasing spray pressure increases the number of smaller droplets.
The other drift problem is associated with pesticides that have a low vapor pressure and is termed "vapor drift." Vapors or gases can drift in harmful concentrations, even in the absence of wind. Phenoxy herbicides and some of the newer herbicides may form vapors after application and the vapors drift to susceptible crops such as cucurbits.
There are several steps that can be taken to prevent damage to non-target plants. When several pesticides are available, the applicator should strongly consider the likelihood of drift when making a choice. The applicator should use formulations and methods of application that will result in minimum drift. Pesticides should be selected that are safe for both target and non-target plants if possible. This can be accomplished by reading the pesticide label and its Material Safety Data Sheet (MSDS).
The period of pesticide residual activity varies greatly from one class of pesticides to another. Persistence directly relates to chemical structure, rate of application, soil type or texture, temperature, soil moisture conditions, rainfall timing, and other factors. Pesticide applicators must be familiar with persistence of each pesticide that may be applied to cucurbits, especially when herbicides are used on previous crops. The applicator must also be aware of adjacent areas that may be affected.
Longevity plays an important part of pest control, since successful pest control requires knowledge of pesticide persistence to make subsequent applications. For example, herbicides used for pre-emergence weed control generally persist for 60 to 90 days, and post-emergence herbicides last from 1 to 2 days to 3 or 4 weeks, depending upon the specific mixing instructions for certain pesticide combinations and fertilizer and pesticide combinations.
Many herbicide and insecticide labels list plant-back times. These dates restrict the time from application until the listed crops can be planted. Plant-back times are on labels for two major reasons. One reason is that the pesticide will damage the crops listed on the label. The second reason is the chemical company has not conducted the required studies to receive a tolerance for that pesticide on the listed crops. Thus, if the listed crop was planted, there is a likelihood of that crop having illegal residue.
Cucurbit growers should be aware that some cucurbits especially squashes can adsorb chlorinated hydrocarbon pesticides from the soil. The chlorinated hydrocarbons are best known as DDT, chlordane, and heptachlor. These insecticides were used extensively in the 1950s and early 1960s. Because they have long half-lives, they are still present in the soil at very low levels. Growers supplying produce to specialty markets may want to have their soil tested for the presence or absence of chlorinated hydrocarbon insecticides.
The Environmental Protection Agency (EPA) issued a Pesticide Regulation Notice addressing the question of tank mixes. This notice recognized the fact that various tank mixes had been tested and recommended by the Agricultural Experiment Stations and State Department of Agriculture, or were common agricultural practices, but directions for tank mixing did not appear on the appropriate labels. EPA has ruled that such uses are not inconsistent with the label provided the following criteria are met:
The applicator assumes the liability and risk in applying tank mixes when instructions are not specifically given on the label.
Even when pesticides are approved for use in a mixture, problems may result.
Formulations of a particular pesticide may vary from one product to another,
and incompatibility may result from the different wetting agents, solvents,
and other additives in them. Liquid formulations are particularly susceptible
to incompatibility problems due to the many additives they usually contain.
Incompatibility is expressed in different ways but a crystalline precipitate
or a gelatinous mass is common, which would require time to clean out plugged
nozzles, screens, and regulators.
Another common problem is a break in the emulsion in which the different ingredients
separate out, as would oil and water. This is the result of the emulsifier being
destroyed, and spray injury is likely to result. Sometimes the addition of soluble
salts to the spray tank will cause an emulsion to break. Separation can also
take the form of particles clumping together. Incompatibility can also result
in lessened activity of the combination although no visible problems can be
seen. The combined materials inactivate one another, and the resulting mix will
be less effective.
Hardness of water may also affect a pesticide or mixture of pesticides. Phosphate and carbonate materials are more susceptible to high alkalinity (high pH) than other pesticides. The addition of lime, lime sulfur, Bordeaux mixture, or other highly alkaline materials may cause decomposition, loss of toxicity, or phytotoxicity. Bacillus thuringiensis is often degraded when used with high alkaline fungicides such as Bordeaux or other copper-containing fungicides.
Combinations of oil or petroleum solvents with organic chemicals are very injurious to plants. Many emulsifiable concentrates are formulated with petroleum solvents and fall into this category. Sometimes one or both pesticides precipitate or fall out of the mixture, and spray injury to the crop results. In other cases, mixing may cause excessive residues, although no precipitation is noticeable in the tank.
Most emulifiable sprays are oil-in-water emulsions producing small particle sizes. When difficulties in emulsifying an oil-or pesticide-in-water spray are encountered, correct them by adding just enough water to cover the agitator, then start the engine and run the agitator and the pump at full pressure to force the liquid through the by-pass return to the tank. If an additional or separate emulsifier is used, it should be added to the tank before adding the pesticide or oil. The pump should be allowed to run for 2 or 3 minutes. Once this emulsion is formed, add the rest of the water to fill the tank while the pump and agitator are running.
Although incompatibility may still be a problem, it can frequently be reduced to the minimum by:
Many of the principles for using tank mixtures of pesticides also apply to fertilizer-pesticide mixtures. Remember these mixtures, either wet or dry, should be handled as pesticides not fertilizers. Also, unless specified on the pesticide label, water carries the pesticide. This means that to mix pesticides with fertilizer, one has to also mix the pesticide with water and fertilizer unless the pesticide label allows for mixing with fertilizer as the carrier.
Pesticides are precision tools. The total quantity of a pesticide in the tank may be less than the accepted variation in fertilizer application, which may vary from a ±10 to 15 pounds per acre. Timing, placement, and distributions are frequently different for pesticides and fertilizers. Compromising one requirement may limit the usefulness and safety of the mixture.
Where tank mixtures are to be used, make sure that agitation is adequate to maintain the suspension. Suspensions also require about 1 to 2 gallons of spray carrier for each pound of product to be suspended. Some products are specifically formulated for use in fertilizer mixtures. Others specify the need to check emulsion stability and add a compatibility agent if needed.
An adjuvant (supplementary) is a substance added to the spray mixture to aid or improve the performance of the main ingredient.
Pesticides, whether emulsifiable concentrates or wettable powders, are formulated for general performance purposes under average conditions. For many jobs they perform satisfactorily, but there are also many situations where they fall short of the desired effect. For example, in very hard or soft waters, a formulation may have too little or too much emulsifier, leading to mixing or excessive foaming problems. A formulation may evenly distribute a pesticide on the leaves of plants that are not waxy, but on plants with waxy leaves, the spray may form small, round droplets instead of spreading as an even film over the leaf surface. It then runs off the plant and onto the ground, leaving no deposit to protect the plant. The addition of an appropriate surfactant to the spray tank will solve this problem.
Adjuvants may be added to the spray mixture to:
Depending upon their intended use, adjuvants are also referred to as emulsifiers, wetters, stickers, extenders, spreaders, penetrants, foaming agents, anti-foaming agents, etc.
Adjuvants are highly active materials. In most cases, a very small quantity will have great effect. Use only the amount recommended. Too much adjuvant may be just as bad as too little. It makes little difference whether the pesticide runs off the foliage because it balls up or because it forms too thin a film on the foliage. Many products contain adjuvants and additional adjuvants may cause problems such as the loss of herbicide selectivity and producing injury on normally tolerant plants. The label should be the guide on the addition of adjuvants.
Effective control of insect, disease, and weed pests in vegetable crops depends on using proper methods of applying pesticides. The goal for applying insecticides, fungicides, and herbicides in cucurbits is to obtain uniform coverage. Uniform coverage in the plant canopy is particularly important for controlling insects and diseases. Proper sprayer design, operation, and maintenance are essential for getting the most out of pesticides.
1. Use proper boom and nozzle arrangement. The arrangement and number of nozzles positioned on a boom depends on the type of crop sprayed. Young plants can be sprayed adequately with a single nozzle per row. As plants get larger, the number of nozzles should be increased. With a sufficient number of nozzles, good distribution of the pesticide within the crop canopy can be achieved.
2. Select the correct nozzles. Nozzle selection is extremely important to get control of pests. Several types of nozzles can be used with ground sprayers, each designed for a specific use. Manufacturers of nozzles have an array of sizes and types of nozzles available. Nozzle selection should be based on 1) type of pesticide to be used, e.g. insecticide, fungicide, or herbicide; 2) nozzle spacing; and 3) amount of pressure to be used. For insecticides, hollow-cone type nozzles are generally recommended because they deliver a smaller and more uniform droplet than a fan-type nozzle. Smaller uniform droplets provide for better penetration of the plant canopy. Alternatively, flat fan-type nozzles are best suited for herbicides where larger droplets are desirable to minimize spray drift. Recently, systems have become available to allow rapid exchange of nozzles from one type to another (i.e., flat fan to hollow cone). These quick connections allow the change of nozzles in a matter of minutes without the use of tools. Additionally, manufacturers have recently developed nozzle technology that reduces the potential for drift from nozzles during the application of pesticides. Spray operators should look into these new improvements in sprayer technology.
3. Select proper volume and pressure. Using the correct volume of spray is essential for getting good coverage of the plant canopy. For most crops, at least 35 gallons per acre is recommended to adequately cover the foliage. Large squash or watermelon plants may require higher volumes of spray to do a good job, perhaps up to 100 gallons per acre. Maintaining the proper pressure in the spray boom is also critical for a good spray job. Lower pressures are often used for herbicide applications to reduce the potential for drift. For good penetration of insecticides and fungicides into the plant canopy, pressures greater than 40 psi are usually desirable. However, as pressure is increased, drift may become a problem. Pressure gauges should be positioned on the boom as well as on the line coming from the pump. Adjustments to the pressure should be made using the gauge on the boom as the index of final delivery pressure.
4. Check compatibility of mixtures. When using more than one pesticide at a time in a sprayer or when foliar fertilizers or other additives are used with the spray, it is important to make certain that the spray mixture is compatible both physically and chemically. Read each label to determine if any products forbid mixing with certain other products. Problems are more commonly observed when a wettable powder formulation is mixed with a liquid pesticide. If uncertain whether two products are compatible, a small-scale test ("jar test") should be conducted. To do this, add to 1 pint water, 1 1/2 teaspoon for each pounds per acre recommended of the wettable powder, followed by 1 teaspoon for each quart per acre recommended of the liquid pesticide. Next, shake the jar and let it stand for a few minutes to see any adverse reaction of the two products. When two products are not compatible physically, the products will sometimes separate abnormally, form layers when mixed with water, or a precipitate or greasy film will form in the mixing container. If problems occur with compatibility, the two products may need to be sprayed separately, or in some cases, a compatibility agent can be added to solve the problem. When mixing different formulations, they should be added to the water carrier in the following sequence: 1) wettable powders, 2) flowables, 3) water solubles, 4) adjuvants [such as spreader-stickers], and 5) emulsifiable concentrates. Pre-mix wettable powders in a separate container, then pour the slurry into the spray tank. Otherwise, wettable powders may clump and can stick to the sides of the tank.
5. Adjuvants are sometimes used with insecticides and fungicides to provide better adherence of the product to the plant. Alternately, adjuvants for use with herbicides are designed to help the herbicide penetrate the weed plant. Most insecticides and fungicides are formulated with appropriate adjuvants to improve spreading and sticking to the plant. Labels of each pesticide should be consulted to determine if a particular adjuvant is recommended or forbidden. Before widespread use, an adjuvant should be used with the pesticide on a trial basis to make sure that it works as desired and that no compatibility problem or phytotoxicity results.
6. Check the water pH. pH refers to the level of acidity or alkalinity in any material. Water varies greatly in pH depending on the source. Water used for sprays should be near pH 7.0 (neutral) and be free of suspended particulate matter. Many pesticides are sensitive to degradation at pH levels outside of the range of 6.5 to 7.5. Therefore, water should be checked with a test kit or meter and then buffered to near 7.0. Test kits or inexpensive and meters can be obtained through most agricultural pesticide dealers. Water that is above 8.0 (alkaline) can break down many insecticides in a matter of hours. When the pH of the spray solution needs to be adjusted, the final pH (after all pesticides are added) should be checked to make sure that no alteration has occurred as a result of one of the pesticides being added.
7. Spray when weather conditions are favorable. Sprays should be applied when spray drift and the likelihood of wash-off by rain are minimal. In general, sprays should not be applied if wind speeds exceed 10 mph or are less than 2 mph. If necessary, sprays should be applied in early morning or at night, when wind speed is typically low but not calm. If rainfall is expected within 8 hours of a spray application or if more than 2 inches of rain is likely within a day of spraying, wash-off of the spray can be a problem resulting in less than expected control of the pests. However, to control some diseases, it is better to apply the protectant fungicide on the crop in advance of rain. See the management of diseases section for more information. Be aware of the impending weather conditions and adjust the spray schedule if necessary to avoid these problems.
8. Calibrate the sprayer regularly. Because sprayer parts wear and get out of adjustment, it is very important that a re- calibration be done regularly. A slight error in the output of the sprayer can result in not enough or too much pesticide being applied. The end result is often poor pest control, wasted product, or sometimes, damage to the crop and environment. Ineffective and inefficient applications can be avoided by calibrating the sprayer on a regular basis. Several techniques can be used for calibration. One method is given in this section and sprayer operators can check the Oklahoma Extension Agents' Handbook of Insect, Plant Disease, and Weed Control, publication E-832 for detailed instructions for sprayer calibration and calculations.
A properly maintained and adjusted sprayer is a key component for the application of pesticides. When spray equipment is worn or poorly calibrated, application effectiveness suffers and can result in wasted material and poor control of the target pest.
Prior to calibrating, equipment should be serviced and all nozzles checked for uniform output and pattern and to be sure that they are all the same type of nozzle. To service the sprayer, all hoses and connections should be inspected for aging, damage, and leaks and the pump should be inspected for output and leaks. Following this, each nozzle, screen, and strainer should be cleaned and inspected, at which time the sprayer is ready for calibration and use. After the sprayer has been used, be certain to rinse out the spray tank with clean water and follow that with partially filling the tank and running the sprayer to clean nozzle tips and screens.
Selection of nozzles should be based upon the type and volume of material that will be sprayed. Nozzles come in a large array of designs and materials as shown in the table below, but the producer should be acquainted with newer innovations in nozzle technology. Select nozzles that will spray the pesticide with the least amount of off-target drift. Generally speaking, nozzles with higher spray angles, i.e., 110° angle vs. 80° angle, can be operated at a lower boom height, thus reducing the potential for drift to occur. Other recent innovations include nozzles that create a larger droplet size, which reduces the potential for drift.
Table 17. Spray nozzle material qualities
There are many ways to calibrate a sprayer and most are effective. When getting started, it may be best to calibrate using more than one method. If the same calibration is completed with two different methods, then the operator has a good indication that calibration is correct. The following steps provide one method of calibration, but other methods can be found in the Extension Agents' Handbook of Insect, Plant Disease, and Weed Control, E-832.
1. Use the table below to determine the distance to drive the tractor and sprayer in the field. Use the nozzle spacing on the boom, or for directed and banding sprays that utilize more than one nozzle over a given row, use the row spacing. Mark off this distance in the field.
2. Attach all equipment to the tractor that will be used for spraying and fill the spray tank half full with water. Next, select the desired gear and throttle settings and drive the course in the field that was measured off in Step 1. Be certain to provide a starting line for the course that will allow the tractor and spray rig ample time to come up to operating speed prior to starting the timing. Using a stopwatch, determine the amount of time required to drive the marked off distance. Timed drives should be repeated, recorded and those recorded times used to calculate the average time to drive the measured distance.
3. Using the average time determined in Step 2, the calibrator can then capture the sprayer discharge for that amount of time in a container graduated in ounces. For broadcast sprayers that have even nozzle spacing, capture the discharge from one nozzle. For directed sprayers that use multiple nozzles over a given row, capture the discharge from all nozzles for a given row and combine.
4. The total amount of discharge collected given in ounces from Step 3 are equal to the gallons per acre that will be applied.
5. Check each nozzle on the spray boom by repeating Steps 3 and 4.
If nozzle discharge amounts vary more than 10% from the average for the entire
boom, then replace the nozzle. Spray volume can be adjusted sev
eral ways including changing the speed of the spray rig, changing nozzle size,
or increasing or decreasing pressure with the pressure regulator. Be aware that
increasing pressure will result in smaller spray droplet size, and drift potential
will likely increase. Increasing pressure to increase a spray rate should be
used only when altering speed or nozzle types have already been used. Nozzle
manufacturers can provide information about the flow rates and approximate pressures
which a given nozzle is designed to operate. Be informed of this information
and calibrate the sprayer to operate within the suggested ranges.
Calibrate the sprayer to apply Curbit 3EC as a post-plant application immediately following seeding of the 10-acre patch of cucumbers. Use a rate of 3 pints of Curbit 3EC per acre with an overall (water plus herbicide) rate of 20 gallons of spray material per acre. The sprayer utilizes flat-fan nozzles spaced 18 inches apart and has a 200-gallon tank.
Step 1: Measure a distance of 227 feet in the field to be sprayed (based on the 18-inch nozzle spacing).
Step 2: Fill the spray tank half full of water, choose a throttle and gear setting, and then drive the measured distance in the field and time it with a second hand or stop watch. Record and repeat, then determine the average time required to drive the distance (for this example assume an average time of 40 seconds).
Step 3: Sitting still, set the throttle at the same setting as used to run the timed course and engage the spray pump with the pressure regulator set at the mid-range recommended for the spray nozzles being used. Catch one nozzle's output with a container marked in ounces for 40 seconds (time required to travel 227 feet).
Step 4: Measure the amount of spray output caught in ounces. If the amount caught equals 20 ounces, then the sprayer is adjusted correctly. If the output does not equal 20 ounces then it can be adjusted by changing the tractor speed or nozzle size or by adjusting the pressure regulator.
Step 5: Recheck the nozzle output for each nozzle on the spray boom. If a given nozzle's output varies more than 10% (if the average is 20 ounces then output could vary 2 ounces, i.e., as low as 18 and as high as 22 ounces) from the average for the entire boom, then replace that nozzle and check again.
How much water/herbicide mixture will it take to spray 10 acres?
10 acres x 20 gallons/acre rate=200 gallons of spray mixture.
How much Curbit 3EC will it take to spray 10 acres?
The label gives a rate of 3 pints per acre of Curbit 3EC. Therefore 10 acres x 3 pints/acre rate=30 pints of Curbit to be added to the water in the spray tank. To convert this to gallons take 30 pints/8 pints/gal=3.75 gallons of Curbit 3EC.
How does one mix all this to make sprayer load?
First, the total amount of spray material needed is 200 gallons. Next, subtract the amount of herbicide to add to the load from the total amount, i.e. 200 gallons for the entire load 3.75 gallons of herbicide=196.25 gallons of water. To mix the load, add approximately half of the water to the spray tank, add the herbicide, and then add the other half of the water to complete the spray mixture. Last, be sure to mix the load well by running the pump several minutes to re-circulate the mixture with the spray boom turned off.
Spray the 20-acre cantaloupe field to control cucumber beetle. Calibrate the
sprayer to apply 1.25 lb. of Sevin 80WSP insecticide per acre with
an overall rate (water plus insecticide) of 40 gallons of spray material per
acre. The application will be made with a directed spray spaced on 80-inch row
centers. The sprayer utilizes 3 hollow cone nozzles per row and has a 200 gallon
tank.
Step 1: Measure a distance of 51 feet in the field to be sprayed (based on the 80-inch row spacing).
Step 2: Fill the spray tank half full of water, choose a throttle and gear setting, and then drive the measured distance in the field and time with a second hand or stop watch. Record and repeat, then determine the average time required to drive the distance (for this example assume an average time of 15 seconds).
Step 3: Sit still, set the throttle at the same setting as used to run the timed course and engage the spray pump with the pressure regulator set at the mid-range recommended for the spray nozzles being used. Catch the output from 3 nozzles that are directed over one row spacing for 15 seconds (time required to travel 51 feet) with a container marked in ounces.
Step 4: Combine and measure the total amount of spray output caught from the 3 nozzles in ounces. If the amount caught equals 40 ounces then the sprayer is adjusted correctly. If the output does not equal 40 ounces then it can be adjusted by changing the tractor speed or nozzle size or by adjusting the pressure regulator.
Step 5: Recheck the nozzle output for each nozzle on the spray boom. If a given nozzle's output varies more than 10% (if the average is 13.3 ounces then output could vary 1.3 ounces, i.e. as low as 12 and as high as 14.6 ounces) from the average for the entire boom, then replace that nozzle and check again.
How much water/insecticide mixture will it take to spray 20 acres?
20 acres x 40 gallons/acre rate=800 gallons of spray mixture.
How much Sevin 80WSP will it take to spray 20 acres?
The label gives a rate of 1.25 pounds per acre of Sevin 80WSP . Therefore 20 acres x 1.25 pounds/acre rate=25 pounds of Sevin 80WSP to be added to the water in the spray tank.
How does one mix all this to make sprayer load?
First, total amount of spray material needed is 800 gallons. Since the insecticide is a dry material do not be concerned about subtracting its volume from a tank mix. Remember, the sprayer tank holds 200 gallons of spray mix and a total of 800 gallons of spray, divide the gallons of total spray mix by the gallons that a spray tank will hold, i.e. 800 gallons/200 gallons per tank=4 tank loads. Next, divide the total amount of insecticide needed by 4, i.e. 25 lbs/4 tank loads=6.25 lbs of Sevin 80WSP per tank load. Next, to mix the load add approximately half of the water to the spray tank, add the insecticide, and then add the other half of the water to complete the spray mixture. Last, be sure to mix the load well by running the pump for several minutes to re-circulate the mixture with the spray boom turned off.
All pesticide containers should be pressure or triple rinsed immediately upon emptying. This should be done at the mixing/loading site, and the rinse water placed in the spray tank. Plastic or steel containers are to be crushed and disposed in a landfill or recycled. Bagged material may be rinsed upon emptying if the bag is lined with water-repellant material. The rinsate is placed into the spray tank for disposal. Bags can then be disposed in landfills. Neither bags nor plastic containers can be burned in Oklahoma. OSU Fact Sheet F-7462 "Rinsing and Disposing of Pesticide Containers" provides further information on various pressure rinsing devices. Never burn or bury pesticide containers.
The Endangered Species Act (ESA) affects all federal programs and agencies. Since EPA registers pesticides, pesticides are covered under ESA. It applies to all outdoor applications of pesticides.
Basically, no person may take action that might harm or kill a federally endangered or threatened species. This includes affecting the species habitat or food source. Cucurbit pesticide applicators are responsible for determining if their actions harm endangered species in the area they are treating. The local Cooperative Extension office, pesticide coordinator, U.S. Fish and Wildlife Service (USFWS), and State Department of Agricultural Inspector can provide information on location of endangered or threatened species.
This regulation is under the U.S. Fish & Wildlife Service. The Act protects almost all migratory birds. Birds not protected by the Act are English sparrows and starlings. All other birds cannot be killed or harassed without getting special permits from either the USFWS or the Oklahoma Department of Wildlife Conservation. Producers that need assistance with managing bird pests can contact USDA/APHIS Wildlife Services at 405.521.4039.
A number of federal and state regulations affect pesticide applications and water quality.
Whenever a sprayer is loaded with a pesticide, there must be an anti-siphoning device attached and a working or a physical air gap between the hose and the sprayer. This prevents back siphoning that occurs when the hose is placed inside the sprayer, causing water pressure to drop and siphoning of the sprayer tank contents into the water line.
All applications of pesticides must be done in such a way as to prevent possible runoff into streams, rivers, ditches, or lakes. This ensures that no pesticide runoff contaminates local surface water.
Many pesticide labels have warnings about the potential for runoff or leaching. The applicator assumes responsibility to ensure the application does not result in contamination of water sources. This can be accomplished by knowing the soil type and depth to groundwater.
If a pesticide application occurs on soil where the water table is high or the soil is susceptible to leaching, the applicator needs to ensure the application does not lead to potential leaching of the pesticide into the groundwater. OSU Fact Sheet F-7459 "Pesticides in Groundwater" can provide useful information on this. County Conservation District offices have information on the depth to groundwater for the soils in each county.
Applicators should survey their facilities and mixing areas to ensure spills and every day procedures will not contaminate ground or surface water.
The EPA has been working to revise the bee warnings on pesticide labels. They are attempting to insert wording that would specify the number of hours or days at which a pesticide is toxic to bees and the hours or days the pesticide cannot be used when bees may be foraging on plants that are blooming, pollen-shedding, or nectar producing.
The bee requirements vary, but generally state pesticide applications are not allowed if bees are visiting the plants. The applicator determines if bees are present, and implements what each label specifically states in regards to bees.
Growers, applicators, and bee handlers need to work together to avoid massive bee kills. Often, pesticide applications can be made late in the evening at a time when most bees have returned to the hive. See the section under management of insects and mites for more information.
Sevin (carbaryl) is the major insecticide that causes massive bee kills. Bees pick-up the dried spray particles from Sevin applications and take the insecticide back to the hive. Most of the other pesticides, especially insecticides, kill only those bees that are sprayed.
The greatest hazard from pesticides is skin contact that results in absorption through the skin. Research has found absorption through the skin to be responsible for over 80% of the poisoning cases from agricultural and industrial use of pesticides. The contact could be from a splash, spill, or drift when mixing, applying the chemical, or from contact with a pesticide residue after application.
Cuts, abrasions, scratches, scuffs, or other damage to the skin increases the hazard of skin absorption. However, even in these lower absorption areas, penetration can be great and will vary from pesticide to pesticide. For example, carbaryl (Sevin) is thought of as a relatively safe material, but absorbed through the skin of the forearm is about seven times more rapidly than malathion or Capture. Studies show pesticides can be absorbed within a few minutes; therefore, waiting until the job is done to wash spills or splashes on the skin may be too late.
Wash by rubbing the hands together or with a piece of cloth using detergent or soap. Do not scrub with a brush, since the outer protective layer of skin may be scratched enough to permit more rapid absorption of any pesticide not removed. Hands should be protected with gloves when working on spray equipment.
Since dermal toxicity is a major concern, the EPA has specified shoes and socks, long-sleeved shirt, and long-legged pants as the minimum personal protection equipment (PPE) required for any pesticide application.
If pesticide applicators choose one piece of PPE, it would be gloves. When selecting gloves, remember they come in different sizes, and not all hands are the same size.
Ensure the glove will not interfere with other operations that must be done while wearing gloves. If this occurs, accidents are likely to follow. Dexterity is very important when selecting gloves. If dexterity is not considered, it is likely the glove selected will not perform as desired and will not be used. Also consider the durability of the glove. If the glove will be exposed to rough surfaces, the glove must withstand the friction and not have small or large holes worn into the glove.
When a number of pesticides are being used, observe the gloves to see how they react with the various pesticides. If the gloves are "bubbling" or "blistering," switch to another type of glove material for the pesticide being applied. There is a chemical reaction occurring between the pesticide and the glove in which the glove is being broken down.
Do not use latex gloves because they will not provide the required protection. Instead, use nitrile, neoprene, or similar type of glove material. Do not use cloth or leather gloves for PPE because they absorb the pesticide, and the glove cannot be cleaned. Only use these gloves as an outer glove with PPE underneath the cloth or leather gloves. When this is done the cloth/leather gloves must not be used for other uses. They should be destroyed after each job.
Liners or gloves with liners are generally more comfortable to use and easier to remove. However, if the liner becomes contaminated with the pesticide, the hand also becomes contaminated. Therefore, liners should only be used when one can ensure the liner will not become contaminated with the pesticide.
Removal of gloves is generally easy; however, they are also the first area of contamination. Gloves should be washed before attempting removal. After washing, one should grasp the cuff of a glove and remove that glove by inverting it. That is, pull the glove off inside out. Then with the clean "free" hand grasping the inside of the glove just removed, grasp the cuff of the other glove and remove that glove. Then wash hands again.
Foot protection is important when using pesticides. During the mixing/loading, application, and sprayer cleaning process the feet are potentially exposed to pesticide concentrate and spray mixture. By wearing chemical resistant footwear one can avoid potential contamination to their feet.
When selecting boots for PPE, there are several items to consider. The first item, ensure that the soles have skid-resistant surfaces. Some footwear is extremely slippery when used on smooth concrete or metal surfaces that are wet. Be sure the footwear can withstand the use to which they will be subjected. Also, consider if the footwear is excessively hot. Such footwear will not be worn by applicators. Lastly, consider the ease of putting on and removing the footwear. Remember that boots are not needed when driving between jobs or during most of the day just when foot exposure to pesticides may occur. Therefore, the footwear must be easily worn and easily removed. Otherwise, they should not be used at all.
Eyes are sensitive to pesticide harm and should be protected with goggles or a face shield. If a pesticide is splashed into the eye, immediately flush the eye with a gentle stream of clean running water or eye flushing solution for 15 minutes while holding the eyelid open. A few seconds delay could increase the extent of the injury. Do not use chemicals or drugs in the wash water as they may increase the injury. Convenient, plastic-eye wash bottles and holders are available. These bottles can be purchased from chemical laboratory suppliers and are called "eye-wash stations." Whether one chooses to use clean water or commercial solutions, these need to be changed periodically to ensure their safety and "freshness."
Most applicators do not believe that inhaling pesticides causes a serious hazard. Inhalation rates second in importance to skin contact in toxicity concerns. Because the lungs have such a large and highly absorptive surface area, even small amounts of a pesticide may be hazardous. Vapors and extremely fine particles, 10 microns or smaller, are a particular hazard. Spray particles of this size can move deep into the lung and reach the area of the lung where the blood vessels take in oxygen. This is an extremely critical area of absorption of materials into the blood stream.
Respirators should be worn when required by the label and when the applicator deems it necessary regardless of label requirements, such as when small spray particles may be present. Occasional use of a moderately toxic pesticide not requiring a respirator may not pose a risk. However, daily use of such a pesticide may greatly increase exposure and may require use of a respirator to decrease the risk (exposure).
EPA's Worker Protection Standard (WPS) does affect all pesticide applications to cucurbits.
WPS is targeted to protect farm workers from pesticides. Farms that consist of immediate family members only (spouse, children, stepchildren, foster children, parents, stepparents, foster parents, brothers, sisters) are not subject to certain aspects of WPS. Immediate family members are only subject to the Restricted-Entry Interval (REI) and personal protective equipment (PPE) standards of WPS.
Under WPS, employers are responsible for the safety of their employees when pesticides are used. Employees are broken into two groups: handlers, employees who work with pesticides, and workers, employees who do not work with pesticides but do chores related to crop production. Handlers include all aspects of pesticide use including transporting pesticides from a purchase point or the cleaning of a sprayer or for cultural decisions including pest control are included as handlers. Workers are hoe hands, irrigation personnel, weed pullers, harvesters, etc.
All pesticides that are used for crop production will have WPS instructions listed within the Agricultural Use Requirements box on their labels. These instructions will specify the type of PPE required for application and early entry, the REI, generic posting, notification, and other required information.
Re-entry requirements have been established for cucurbit pesticide applications. The minimum REI is 4 hours. The maximum REI can be 72 hours for pesticides used where less than 25 inches of rainfall drops yearly and the normal REI is 48 hours.
Workers are not to enter treated fields until the REI has expired. They may enter in case of an emergency and then only after 4 hours have elapsed from the time of application. Even then workers can only be in the treated area for one hour in a 24-hour period for early entry. When workers are under early reentry they must wear the PPE required for application.
Workers who enter the treated area within 30 days after the REI has expired must be provided decontamination facilities. The facilities consist of single use towels, soap, and enough water for flushing eyes and washing hands. It is best to provide separate eye washing facilities. The water does not have to be potable but it is recommended. A handy water jug will often suffice for a worker decontamination water facility.
There are basically three types of posting:
1. Generic posting is the sign with the face and hand. Generic posting is only required when so stated on the label. Generic posting, when required, must be done no sooner than 24 hours before the scheduled application and removed within 3 days after the REI expires. Generic posting is to go up at a common point of entry into the field if a worker will be either in the field during the REI or come within 1/4 mile of the field.
2. Notification posting is required for all pesticides used. Notification posting is done at a common point where workers congregate. This posting provides the following information: a) location and description of the treated area; b) product name, EPA registration number, and active ingredient(s); c) time and date of application; and d) the REI. The safety poster is required for all pesticides. It is to be posted where workers congregate.
3. The safety poster is a standard poster on worker safety regarding pesticides. Remember the generic poster is only required when the label requires it. Some labels may also require oral notification and warning to workers.
WPS will require good management to prevent production problems from occurring involving such situations as an extended REI when harvesting or other activities are in a treated field.
Employers are to provide workers and handlers with all the necessary PPE. Employers are also to ensure the PPE is in proper working order and to clean the PPE before each use.
Persons operating a u-pick operation should realize WPS does not include persons who are not employed. Thus, persons coming to the farm to pick cucurbits in a u-pick operation are not covered by WPS; however, the grower and employee(s) are covered by WPS.
WPS information may be obtained from the County Extension Office, Pesticide Coordinator's office at Oklahoma State University, or from the Department of Agriculture office. Every applicator and employer should have the How-to-Comply manual and other material developed by EPA on WPS.
The pesticide applicator, employees, and customers may be exposed daily to many pesticides ranging from low to high toxicity. Cucurbit pesticides must often be applied in environments frequented by humans. The pesticide applicator must be constantly alert to potential management problems associated with this situation. Primarily, the problem is twofold: prevent undue applications of pesticides, and prevent humans from contacting hazardous amounts of pesticides within the treated area. To avoid problems as much as possible, the following safety precautions should be followed:
Information on worker safety, REIs, and use of personal protective equipment (PPE) can be found on pesticide labels in the Agricultural Use Box. An example follows.
Use this product only in accordance with its labeling and with the Worker Protection Standard, 40 CFR part 170. This Standard contains requirements for the protection of agricultural workers on farms, forests, nurseries, and greenhouses, and handlers of agricultural pesticides. It contains requirements for training, decontamination, notification, and emergency assistance. It also contains specific instructions and exceptions pertaining to the statements on this label about personal protective equipment (PPE), and restricted-entry interval. The requirements in this box only apply to uses of this product that are covered by the Worker Protection Standard.
Do not enter or allow worker entry into treated areas during the restricted entry interval (REI) of 24 hours.
Exception: if the product is soil-injected or soil-incorporated, the Worker Protection Standard, under certain circumstances, allows workers to enter the treated area if there will be no contact with anything that has been treated.
PPE required for early entry to treated areas that is permitted under the Worker Protection Standard and that involves contact with anything that has been treated, such as plants, soil, or water is:
The example above provides the applicator with information to address the major points of the WPS. First, when can workers re-enter the field? In this case, workers must stay out of the field for 24 hours after the pesticide is applied. Second, what safety equipment (PPE) is required? This pesticide requires coveralls, chemical-resistant gloves with at least 14-mil thickness, and the use of shoes and socks. All pesticides require the use of long sleeved shirt, long legged pants, and shoes with socks. This is the minimum PPE required.
Workers are those that perform agricultural product tasks that do not include the use or transport of pesticides. This includes working on or cleaning sprayers. Handlers are agriculture employees who work with pesticides. This could be operating a sprayer, cleaning/maintaining the sprayer, scouting, etc.
Selection can begin once pesticides and their affects on humans are known. Selection is almost impossible without this information. Once the pesticide has been selected then the label and MSDS should be consulted for toxicity and personal protective equipment information.
Minimum personal protective equipment (PPE) clothing includes shoes and socks, long-legged pants, and long-sleeved shirt. These items are for all pesticide handling and application activities.
PPE comes in various forms and has different degrees of protection. The simplest is "normal" work clothing meaning long trousers, long-sleeved shirts, socks, and shoes. Clothing should be of a closely woven fabric. The close weave "catches" more pesticide particles in the fabric, thus keeping them from directly contacting the skin. Generally, natural fabrics catch pesticide droplets better than synthetic fabrics. However, natural fabrics may be more difficult to clean. Natural fabrics are better at catching pesticide particle because the fibers are frayed. Synthetics can be effective and multiple washings before use will often fray the synthetic fibers, thus providing catching properties similar to those of natural fabrics. Synthetic fabrics often provide some water repellent properties that increase their effectiveness. However, normal work clothing should be worn only when applying pesticides that permit them on the label and when small amounts of pesticide spray particles are expected to get on the clothing. If one expects to receive large amounts of spray particles on their clothing, then other PPE clothing should be used.
Regardless of whether woven or spun material is selected one needs to be aware of a number of items pertaining to the construction of the PPE.
Once the type of PPE is known, then the applicator must take into account the various aspects of the PPE to be worn. If heat is a concern, PPE that does not "breathe" may be avoided and instead use another type.
In selecting PPE, consideration of the applicator requirements is important. PPE must not bind nor restrict the applicator's movement such that the PPE becomes a greater hazard than the pesticide. Most PPE coveralls and sleeve protectors are bulky. When working around moving parts such as PTO shafts, care must be taken to ensure clothing is not bulky as to get caught in moving equipment.
Disposable PPE clothing is either woven or spun. Woven material is made of closely woven synthetic fibers. These materials are water repellent and very tightly woven, thus greatly limiting spray particles reaching the body. Woven fabrics "breathe" and are relatively comfortable. These fabrics are often treated with water repellent materials. The water-repellent materials increase protection but decrease the material's ability to breathe making them hotter and less comfortable. The other type of synthetic PPE is spun material. The fabric is extruded and does not have a weave. Since it lacks the "holes" woven materials contain, it is much more difficult for spray particles to reach the skin, making it much more protective. Spun materials are more repellent and hotter due to decreased breathing of the fabric. There are newer fabrics with improved breathing ability. Treating spun materials with repellent materials will increase its protecting ability and decrease the materials breathing ability.
It is important to know how PPE is constructed and the strong and weak points at critical areas of the PPE equipment.
Check the garment's seams. There are three types of seams. The simplest is a stitched seam. These can be effective or not depending on the protection needed and strength of the seam. Stitching should be close (tight). This will help decrease the chance of spray particles passing through the seams. Double stitching is better than single because it adds protection and strength. Fusing or welding the fabric pieces together can create another type of seam. Fused seams provide greater protection than stitched, but its decreased breathing would possibly create a comfort concern. The third type of seam is a combination of sewn and fused. This type of seam is the most protective as it provides all the benefits of the two; however, the breathing ability will be decreased. Most fused seams are of sufficient strength; however, they should be inspected before purchasing to ensure integrity.
The choice of woven or spun fabric will partially depend upon the pesticide applied. The other major consideration is comfort. This includes movement, which will be addressed below, and breathability. If one is working in hot or warm conditions, the fabric's ability to breathe can become as important as the chemical protection provided. A woven fabric that has been treated with a repellent may breathe better than a spun fabric. The choice of fabrics will depend upon the individual's circumstances, and may have to be determined by trial and error.
The fastening device can be very important. Buttons provide the least protection because spray particles can pass through or around the loose closure. Velcro can provide a tighter closure; however, spray particles can build up on the Velcro. Drawstrings on pants can create the tight fit needed but like Velcro can become contaminated over time. Pesticide sprays can corrode metal zippers. Plastic zippers can be dissolved if concentrated formulations are spilled on them. Zippers can form a tight or loose closure. A tight closure is desired. One should consider the ease of operating the zipper with gloves. Snaps are similar to zippers and buttons. They have the same problems, as buttons but are generally easier to fasten. Like zippers, certain types of pesticide formulations can damage them. Snaps can also be damaged by being bent, and thus will not fasten. Often each of these can be improved by being inset with a covering flap.
Boots and gloves should be washed with soap and water before removal. Disposable coveralls that receive an excessive amount of spray residue should be rinsed with clean water before removal. These actions provide safety measures for the wearer during the changing and storage process of the PPE.
Once removed, gloves should be washed again in soap and clean water, and air-dried in a location away from pesticides. Cloth coveralls should be washed, if possible, and air-dried also. When washing, use 140°F water, full wash load cycle, use a strong detergent, and wash the clothes by themselves. Do not wash PPE with other laundry. This is to avoid possible cross contamination of pesticide residues with other clothing. Air-dry the clothes. Run another cycle through the washer the same as before to clean the washer drum. Disposable coveralls may be laundered according to manufacturer instructions. An applicator has to make the decision whether to launder disposable coveralls or to use them a specified number of times and then destroy them. When disposable coveralls are laundered they do lose some of their protecting ability.
Respirators are to be washed and dried after each day's use. They may be washed in warm water with mild soap, wiped and hung up to air dry. Likewise, eye protection needs to be washed in the same manner after each day's use. When PPE is to be disposed after cleaning, shred and destroy the PPE so that someone else cannot use it
Producers are considered Private Applicators in Oklahoma. Private Applicators are only required to keep pesticide use records for pesticides classified as Restricted-Use (RUP). For business purposes, it is good to keep records of all their pesticide use. This allows one to have a record of what was used and to recall and reflect on the job the pesticide(s) did under the conditions they were applied.
Records required in Oklahoma to be kept are the following:
The above items are to be kept for each restricted-use pesticide application. Many of them are quite useful for production and efficacy purposes and should be kept for business use.
Farmers are also required to keep these records for the USDA Agricultural Marketing Service Record Keeping requirement.
Compendium of Cucurbit Diseases. 1996. T. A. Zitter, D. L. Hopkins, and C. E. Thomas. APS Press, St. Paul, MN
Cucurbit Diseases: A Practical Guide for Seedsmen, Growers, and Agricultural Advisors. 1988. E. Bernhardt, J. Dodson, and J. Watterson. Petoseed Co. Inc.Delaplane, Keith and Daniel F. Mayer. 2000. Crop Pollination by Bees. CABI Publishing, Wallingford, UK.
Vegetable Diseases and Their Control. 2nd Ed. 1986. A.F. Sherf and A.A. MacNab. John Wiley & Sons.
Vegetable Insect Management: With Emphasis on the Midwest. Rick Foster and Brian Flood. 1995. Meister Publishing Co., Willoghby, OH.
These Fact Sheets are available for free download from the Oklahoma
Cooperative Extension Service's online publications library at agweb.okstate.edu/pearl.
Oklahoma residents
can obtain printed copies of publications by contacting their county Extension
office. Publications can also be ordered through University Mailing Services,
Oklahoma State University, Stillwater, OK 74078; phone: 405.744.5385
F-181 Should I Grow Fruits and Vegetables? Basic Business Development Plan for Horticulture Producers
F-182 Should I Grow Fruits and Vegetables? Non-Direct Marketing for Fruits and Vegetables
F-183 Should I Grow Fruits and Vegetables? Direct Marketing for Fruit and Vegetable Crops
F-184 Should I Grow Fruits and Vegetables? Pick-Your-Own Markets
F-185 Should I Grow Fruits and Vegetables? Farmers Markets
F-186 Should I Grow Fruits and Vegetables? Roadside Stands
F-1215 Selecting Proper Nozzle Type and Size for Low Pressure Sprayer
F-1216 Calibrating a Low Pressure Ground Sprayer
F-1217 The Low Pressure Ground Sprayer
F-1218 Pumps for Low Pressure Ground Sprayer
F-2207 How to Get a Good Soil Sample
F-6000 Fertilizing Commercial Vegetables
CR-6008 Weed Control in Vegetables
F-6020 Growing Vegetable Transplants
F-6023 Slicing Cucumber Production
F-6026 Squash and Pumpkin Production
F-6032 Vegetable Varieties for Oklahoma
F-6236 Watermelon Production
F-6237 Cantaloupe Production
F-7307 Beneficial Insects
F-7451 Agricultural Pesticide Storage
F-7453 First Aid for Pesticide Poisoning (Certification Training Series)
F-7454 Check Your Pesticides Labels (Pesticide Applicator Certification Series)
F-7457 Toxicity of Pesticides (Pesticide Applicator Certification Series)
F-7459 Pesticides in Groundwater
F-7462 Rinsing and Disposing of Pesticide Containers
F-7612 Plant Disease Diagnostic Services
E-832 OSU Extension Agents' Handbook of Insect, Plant Diseases, and Weed Control*
E-929 Guide for Identification and Management of Disease of Cucurbit Vegetable Crops*
Titles marked with an asterisk (*) are paid publications. Contact your county
Extension office or University Mailing 405.744.5385 for current pricing information.