Gasoline is often used to kill weed growth in crops, lawns and ornamental flower beds. However, using gasoline causes problems both environmentally and for the safety of the gardener. While throwing gasoline on pesky weeds sounds like a quick method for weed removal, it is important for gardeners to understand the hazards.

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Keep a cap on the gasoline can at all times.

Environmental

Gasoline doesn't stick to weeds. When gardeners use gasoline to kill weeds, they pour toxic substances on top of soil that sink down into ground water or the storm sewer. In fact, those with wells could pollute their own drinking water. It is difficult to detect gasoline in water. Low levels of contamination may not be smelled or tasted. Throwing a little gasoline on top of a weed may mean contaminating your water source.

Hazard

Gasoline is a major safety hazard for gardeners either treating weeds or even storing the flammable liquid. Furthermore, using gasoline near any source that may ignite the fuel could set off a large fire. Smoking, hot engines, pilot lights and electrical sparks may cause the lawn to bust into flames. Even handling gasoline is dangerous. Vapors from toxic fumes cause health problems. Gloves and a mask must be worn when using gasoline.

Other Factors

Gasoline has a flash point of -45 degrees Fahrenheit. A flash point is the temperature a substance needs before it has enough vapor to support a flame. What this means is that using gasoline when temperatures are below -45 F. is safe enough to not ignite flames. However, gardeners do not kill weeds at that extreme temperature. In addition, gasoline is extremely hard to store when used throughout the season as an herbicide. Gardeners must store gasoline away from the home in a cool dry place where it will not tip over.

Using Gasoline to Kill Weeds

A small amount of gasoline may be sprayed on weed foliage. Covering a yard with gasoline is not safe, but spot treating weeds is effective. To keep the area safe, spray on a cool day. Avoid watering the lawn after spraying the foliage. Focus the spray on the leaves of the weed instead of the soil. Also, keep pets and children away from the weedy area.