Using Pesticides Safely
The key to safe, effective pesticide use is to choose the right product for the targeted pest, then apply the material with the right equipment, at the right time. And always treat pesticides with respect, since even relatively nontoxic products can cause damage if used carelessly.
Follow these rules when choosing and applying pesticides:
- Before you start thinking about which pesticide to use, ask yourself if you've exhausted all other possible forms of control.
- Select the right pesticide for the job. That means properly identifying the pest and the afflicted plant, then making sure the product is approved for use on both. Applying the wrong pesticide wastes time, effort, and money, and it may be harmful as well.
- If more than one pesticide will do the trick, opt for the least toxic choice. Also look for selective products (those which target a few pests rather than a broad range) and products that quickly break down into harmless substances.
- Buy only the amount you can use in one season. Don't be swayed by sales or economy-size packages unless you can share the product.
- Read the label and follow the directions exactly. Use only the recommended amount; don't assume that if a little is good, a lot is better.
- Time your treatments to catch pests at their most vulnerable stage.
- If possible, spot-treat: use pesticides only in problem areas, not on the whole garden.
- If you have any questions about the safety, environmental impact, or proper use of a pesticide, consult your state pesticide agency, your regional EPA office, or the National Pesticide Telecommunications Network, a 24-hour telephone hotline (800-858-PEST) funded by the EPA and Texas Tech University Health Sciences Center School of Medicine.
Reading the Label
This basic rule about pesticide use can't be repeated often enough: read the label. Read the label before buying a product, before mixing it, before applying it, before storing it, and before throwing it away. Don't trust your memory-read the label at every step. The product label is the most important source of information about the pesticide. It's a legal document that tells you a product's effect on human health and the environment; its active ingredients; the pests and crops on which it can successfully be used; how to mix and apply it; whether it can be blended with other materials; whether there's a waiting period between applying the pesticide and harvesting crops or reentering the area; and how to store and dispose of the product (and its container). The label also spells out any special safety measures you'll need, to take.
If you're in doubt about a product's suitability for your situation, the label is the absolute law. Other recommendations, such as those listed in the rogues' gallery starting on page 23, are intended as a guide.
Understanding the Risks
A signal word printed in large letters indicates the relative toxicity of a chemical. "Danger" or "poison" means highly toxic; "warning" means moderately toxic; and "caution" means slightly toxic. Different formulations of the same pesticide often have different signal words: a more concentrated version may rate "warning," a more dilute one "caution."
Consideration should also be given to how often a product needs to be applied. Each application is one more personal and environmental exposure. A product labeled "danger" that is meant to be diluted and applied once every 2 to 3 weeks may actually be safer for the environment and user than a product labeled "caution" that's undiluted and applied every 2 to 3 days. The former are usually more economical as well.
Besides the signal word, product labels also include some text that details risks and notes safety precautions. You may see statements like the following: "Causes irreversible eye damage." "Wear goggles or face shields and rubber gloves when handling." "Do not breathe spray mist." "Wash skin thoroughly with soap and water after handling."
The days-to-harvest figure stated for pesticides that can be used on edible plants tells you how long you must wait between your last application and when you can harvest. This gives a good indication of the residual effects of the product used.
Relative Toxicity of Some Pesticides
Scientists calculate toxicity by LD50 ratings, which refer to the amount of material needed to kill half of the test population. These numbers don't appear on pesticide labels, but are used in determining the signal word. The higher the number, the less toxic the pesticide, The chart below gives ratings for some of the products mentioned on this site.
Basic copper sulfate
Mixing & Applying Pesticides
Mix the pesticide in a well-ventilated area, using a separate set of measuring utensils labeled for pesticide use. Try not to mix more material than you can use in one application. First put the water in a sprayer, then add pesticide—using the opposite order might leave the pesticide at the bottom. Pesticides usually work better if mixed with neutral or slightly acid water; if your water is alkaline, you can acidify it by adding a couple of teaspoons of white vinegar for each gallon of spray. Add the vinegar to the water and swirl it around before pouring in the pesticide.
When handling pesticides, wear protective gear as recommended on the product label, and don't smoke, eat, or drink. Before beginning the treatment, remove pets and toys from the area; also cover birdbaths, fish ponds, and anything else you don't want sprayed or dusted.
Apply pesticides only in still weather. When the air is calm, the material won't drift back onto you or onto plants that you didn't intend to treat. Coat the plant thoroughly, paying special attention to the leaf undersides, where many pests feed.
If you're using a pesticide harmful to bees, apply it late in the day, when bees are less active. If possible, use a spray rather than a dust, since bees are more likely to pick up dusts on their bodies.
Spraying. To prevent injury to your plants, water them thoroughly before spraying-thirsty plants can experience even more water stress when exposed to soaps, oils, or solvents in a pesticide formulation. Let the foliage dry, then apply the pesticide until it just begins to drip off the leaves.
A ready-to-use spray in an aerosol can or trigger sprayer is convenient for a small job. In all other cases, it's more economical to use liquid concentrates and your own sprayer. Good-quality plastic sprayers are an excellent choice: they're lightweight and corrosion-resistant, and it's easy to see how much solution you have.
A handheld trigger sprayer is fine for a few plants or for spot-treating, but squeezing the trigger can be tiring if you're applying pesticide on a large scale. The Bonide Pump-N-Shoot Sprayer comes in handy here. For big jobs, a pressurized tank provides the most precise application. Most home gardeners use handheld models with capacities of 1 or 2 gallons. If you plan to spray a very big garden or a small orchard, you may want to invest in a backpack model. You need a strong back for this apparatus, which holds about 4 gallons of solution.
Another way to get pesticide into a small tree is with an old-fashioned trombone sprayer. You place the hose end into an open bucket of spray mixture, then slide a mechanism near the nozzle end to shoot the pesticide 10 to 20 feet into the tree.
Hose-end sprayers apply spray quickly, but they're not very precise in their calibration or in the way they distribute pesticide. They're most often used for spraying lawns. You put the pesticide in the sprayer, then attach the garden hose; as water runs through the hose, it mixes with the pesticide (the Bonide Dial A Spray dilution rate is fixed on some models, variable on others). Get a model with an on-off switch that can be turned off independently from the water supply. The sprayer or hose should have a backflow preventer so that pesticide won't be siphoned into your water system if the water pressure drops.
Thoroughly clean your equipment after each use. Rinse several times with clean water, then operate the sprayer until clear water runs out of the nozzle. Keep a separate sprayer for weed killers, since any herbicide residue can harm plants that are later treated with other types of pesticides.
Dusting. Dusts adhere better to wet foliage, so mist plants before treating them-but apply dust during a dry spell, or rain will wash away the pesticide. Apply a thin coat; don't layer the material on. Since dusts are irritants, always wear a dust mask, even if you're handling the material for just a minute or two.
Some products come in ready-to-use squeeze bottles, but in most cases you'll need your own applicator. One type of duster has a bellowslike body that you squeeze, forcing the dust out through a nozzle. This device is tiring to use for all but the smallest jobs.
A more common applicator consists of a long tube with a pump that slides to propel a fine stream of dust through the nozzle. Another type of duster, better suited for large jobs, has a handle you crank as you walk along; it delivers a cloud of dust.
Don't keep pesticides in the house. Store them in their original containers in a cool, dark, dry place, such as a locked cupboard in a garage or shaded storage shed (not a metal shed). Avoid areas experiencing extreme fluctuations in temperature: the ideal range is 50°' to 75°F. For details on proper storage of specific chemicals, follow label directions. Most chemical companies formulate their products to last a minimum of 2 years in the container (exceptions are pesticides made from living organisms like Bt), although they can remain effective much longer under ideal storage conditions.
Pesticides don't lose their pest-control powers all at once. Instead of being 100 percent effective after several years, they may perform at only 70 to 80 percent of their original potency. The only reliable way to determine whether a pesticide will still do the job is simply to use it. Even if you write the purchase date on the container, you don't know how long the product sat in the store before you bought it.
Getting Rid of Leftover Pesticides
As long as a product hasn't been banned or restricted, it's environmentally safer to use it up as needed than to throw it away. However, you shouldn't use a product just to get rid of it. Apply it only if there is a problem, and only on the plants and pests listed on the label. If you don't want the pesticide yourself, give it to someone who does. Never dump it onto the soil or pour it down a drain.
If your cupboard holds any banned products, such as those containing chlordane, DDT, lead, or mercury, discard them according to local ordinances.
To get rid of products in your area, click on the below link:
Safe Disposal of Pesticides- US EPA