Incorporate such herbicides as bentazone and glyphosate into your list of available landscaping tools and you'll join millions of gardeners, landscapers and farmers who regularly use the chemicals to control unwanted plants. Dozens of herbicide formulations are available in nurseries and garden stores, and although they have benefits, they also have drawbacks of which you should be aware so you can take appropriate precautions.
Pros: Weed Removal
Herbicides are primarily used to kill unwanted weed vegetation. A wide range of chemicals offer selective control--the herbicide only kills a certain type of vegetation while not harming other plants--and non-selective control, letting landscapers customize their approach to weed management.
Pros: Less Labor
Herbicides save gardeners, farmers and landscapers time and labor compared with physically removing vegetation. This is especially true for wide-scale weed control, as is needed in pastures and for crop farms. Instead of having to physically inspect and work a plot, a gardener can simply mist the entire area with the appropriate herbicide. Pre-emergent herbicides can even keep weeds from growing in the first place.
Pros: Long-Term Weed Control
Some herbicides have residual effects. The chemical lingers in the soil and works long after the original vegetation has died off, keeping weeds at bay for extended periods of time and reducing the need for constant treatment.
Most herbicides are very toxic. Poisoning can result after skin contact--the most common method of contact, according to Texas A&M University--or if the product is ingested or inhaled. Results can range from minor skin irritations to extreme gastrointestinal discomfort.
Cons: Killing Non-Targeted Vegetation
Some herbicides, such as those formulated with glyphosate, are non-selective. Non-selective herbicides kill all vegetation, not just weeds. Improper application or wind drift can kill non-targeted plants. Gardeners using a non-selective herbicide should take precautions to ensure they're only spraying the plants they want to kill.
Herbicides can contaminate the soil and pollute waterways, negatively affecting wildlife and the environment. Improper application or herbicide overuse are common ways that the chemicals end up polluting the ground or water.