What Weeds Does Atrazine Kill?

Herbicides have been the subject of much controversy in the past few decades, particularly after the release of Mark Achbar and Jennifer Abbot’s documentary The Corporation, which set its sights for most of its runtime on the agrochemical company Monsanto’s lack of ethics. At the center of the controversy lies Atrazine, a widely used herbicide that prevents weeds from growing.

The European Union banned the use of Atrazine in 2004, but it’s the leading herbicide on the market in the U.S.

Part of the reason for its popularity is that it’s relatively inexpensive to produce. And it indeed gets the job done when weeds are persistent. Atrazine is most effective dealing with common broadleaf weeds such as Chickweed, Clover, Henbit, Pigweed, Ragweed, Doveweed, Oxalis, Betony, Gripeweed, and Morning Glory.

It also handles most pest grasses like Foxtails, Annual Bluegrass, invasive Bermuda, Quackgrass, and Wildgrass.

It’s so effective because it works as a pre emergent and post emergent.

Does Atrazine Kill Crabgrass?

You may have read reports that Atrazine is effective against crabgrass, and while it does have some effect, it’s not the best product for dealing with the nuisance. There are specialized herbicides for crabgrass that work far better.

I’ve Read Atrazine Kills Turfgrass As Well?

We already mentioned products containing Atrazine such as Round-Up kills most pest grasses, but it isn’t exactly picky what kind of grass it attacks. It’s also damaging to most turfgrasses. If you’re using a product that contains Atrazine, there are only two recommended species of grass to have on your lawn. They are:

  • Centipede Grass
  • St. Augustine Grass

Atrazine kills other grasses; worse, it can stifle regrowth for up to one year after it’s applied. If your lawn is not completely comprised of Centipede or St. Augustine grass, Atrazine should be avoided at all costs.

The Bermuda Problem

Many homeowners have to contend with invasive Bermuda grass when dealing with lawn that has St. Augustine grass. Atrazine is a great choice, killing the Bermuda grass and stopping regrowth for up to six weeks.

Is Atrazine Safe for Garden Plants?

When it was first introduced, Atrazine was designed to be safely used on corn crops. Its chemical composition was designed to knock out a variety of grasses and plants. As a broadleaf killer, it’s not safe to apply on bushes, trees, vegetable plants, or flowers.

How Long Does It Take To Work?

Patience is a virtue when working with Atrazine. It’s a slow-acting herbicide, usually taking up to four to six weeks before showing results. Many weed controls often take effect almost right away, and you start to notice within two weeks. But Atrazine has to fully work itself into the plant systems to get rid of the toughest weeds, meaning it takes three times as long to work.

How to Apply Atrazine

If you’re looking for powerful weed killers for those two species of grass, there’s nothing that works better than Atrazine. It stops weeds from sprouting and kills the ones already in your lawn. But it must be applied correctly for it to really be effective. When using Atrazine, be sure to:

  • Use it in the day, when temperatures are between 55 and 85 degrees Fahrenheit. It’s best applied in the late Spring when weeds are still young.
  • Only apply twice a year – once in Spring and once in fall.
  • Dilute the Atrazine according to the instructions on the label.
  • After use, let the Atrazine dry before pets and children go on your lawn.

These steps ensure that the Atrazine kills as many weeds as possible while still keeping your lawn, and your family, safe. Following these steps also should prevent you from having to apply it more often than twice a year, saving time, money and lowering any risks working with Atrazine present.

The Dangers of Atrazine

In 2003, six studies were released documenting the effects of Atrazine on frogs that are nearby farmland. They revealed severe sexual abnormalities. Some had multiple testes and ovaries, others were born hermaphrodites.

At the time, the Bush Administration began growing concerned and asked the EPA to consider them against other studies that proclaimed Atrazine safe. They noted several spikes in Atrazine in water wells during Spring and Summer.

The frog studies were treated as a dead canary in a coal mine, prompting further studies on the effects of Atrazine on humans.

In 2009, it found that high levels of Atrazine can cause severe birth defects in unborn babies, menstrual problems, and even higher potential for cancer later in life. So when the chemical washes into streams and aquifers, it presents a huge risk.

It also found that corn has a natural immunity to Atrazine, which is why it was so effective at the start of production.

It takes a rather high level to present such risks. It would be extremely difficult to ingest a dose large enough to cause the issues it’s capable of and nearly impossible to get a fatal dose.

Remember, the dose is precisely what makes it poison. We, as a society, rarely stop using something deemed necessary just on the basis that a certain amount of it is lethal. Otherwise, we would still enforce prohibition. The EPA has set a maximum containment level for Atrazine.

But if you think you have reason to be concerned, your grounds are well-founded. The scientist who published the initial frog studies does have some history of strange behavior, but his research appears to be sound. There’s also wide speculation that the attacks on his life were directed by his former employer, Syngenta, to discredit him lest he destroyed their cash cow.

Syngenta, by the way, paid $105 million to settle with nearly 2,000 water utilities in the U.S. Midwest.

There are alternatives to Atrazine, and though you may be using a less effective product, just the peace of mind that you avoided a potentially toxic chemical might be enough to sway you. Ultimately, the decision is yours, and you’ll do what you feel is best for your family and lawn.

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