In This Section |
Precautions
with Pesticides:
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| Author: | OMAFRA Staff |
|---|---|
| Creation Date: | 25 November 2002 |
| Last Reviewed: | 1 August 2005 |
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| Precautions with Pesticides > Protect the Environment |
Do not allow pesticides to drift, run off or leach onto land or water bodies bordering treatment areas. Leave a suitable buffer zone between the treatment area and adjacent areas. No spray droplets should fall on adjacent properties, where treatments are not authorized. Areas of concern are:
Buffer zones are vegetated areas, left untreated to protect an adjacent area, for example a pond, a stream, a sensitive crop, a non-target crop, wetland or woodland, etc.
It is an offence under the federal Fisheries Act to introduce any material into water that may be harmful to fish or fish habitat. To protect these waters, landscape applicators must determine a suitable setback distance between the area to be protected and the area where pesticide treatments are planned. The protected area includes the water body, as well as adjacent riparian (riverbank) areas that contribute to fish food and habitat.
Groundwater is the source of water for wells and springs. If groundwater becomes contaminated with pesticides, it is difficult to clean. Preventing groundwater contamination is crucial. Some pesticides have the potential to leach through the soil to groundwater.
Movement of pesticides into groundwater can make the water unfit for use. However, pesticides applied to the soil are subjected to physical, chemical and biological processes that affect their movement through the soil and their potential for groundwater contamination. Making the right pesticide choices for the situation can help minimize the threat of groundwater contamination.
Soil texture plays a major role in pesticide performance and persistence. Soil organic matter can make a difference in pesticide activity. Therefore, it is important to select a pesticide based on soil type and organic matter content. Chemicals tend to leach more readily in coarse-textured soils with low organic-matter content. In contrast, fine-textured soils with high organic matter are highly adsorptive and therefore have a low leaching potential.
Some pesticides bind strongly (adsorb) to soils and therefore are not easily removed. Clay materials and organic matter favour strong adsorption. Use soil analysis information on organic matter content when selecting pesticides and application rates for your pest management program. Some pesticides are highly soluble in water, which can increase their leaching potential. Leaching of a pesticide can be minimized by pesticide dosage and by the timing and method of application. Choose the right pesticide for your situation.
The rate of degradation by natural processes is highly dependent on both the pesticide class (chemistry) and environmental factors. Sunlight, temperature, soil, pH, microbial activity and other soil characteristics affect the breakdown of pesticide. Some pesticides break down slowly and therefore have a greater potential for leaching. A short-lived pesticide may be degraded before any leaching occurs. Choosing a short-lived pesticide can minimize leaching potential.
Microbial degradation occurs when fungi, bacteria and other soil microorganisms use pesticides as a food (energy) source. High organic-matter content, along with other properties such as optimum moisture, aeration, temperature and soil pH, can enhance microbial degradation. In addition, chemical degradation of pesticides can occur by reaction with water, oxygen and other chemicals. In general, pesticides that are highly water-soluble, relatively persistent and not readily adsorbed by soil have the greatest potential for leaching.
High water tables may be vulnerable to contamination by pesticides and fertilizers due to the relatively short distance between the soil surface and groundwater. There is potential for groundwater contamination in areas with coarse-textured soils and high water tables.
Specific application information for each pesticide is contained on the pesticide label. Careful adherence to application and disposal directions, combined with proper equipment calibration, provide the best method of preventing groundwater contamination.
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For more information about spray drift consult:
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It is important to protect bees when you spray. Honeybees, as well as other bees and insects, are important pollinators of crops. Many crops also offer bees important sources of pollen for honey production.
If you choose to use insecticides for insect control, take these steps to prevent harming bees when you spray:
| Basudin, Diazinon | diazinon |
| Cygon, Lagon | dimethoate |
| Furadan | carbofuran |
| Guthion, Sniper | azinphos-methyl |
| Imidan | phosmet |
| Lannate | methomyl |
| Lorsban, Pyrifos, Pyrinex | chlorpyrifos |
| Malathion | malathion |
| Ripcord, Cymbush | cypermethrin |
| Sevin | carbaryl |
| Decis | deltamethrin |
| Dylox | trichlorfon |
| Endosulfan, Thiodan, Thionex | endosulfan |
Unusually low temperatures at time of application may cause insectides to remain toxic up to 20 times longer than during warm weather. High temperatures in the early morning or late evening may extend active foraging by bees.
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