What's in Roundup® Ready-to-Use Weed & Grass Killer?

When you pick up a Roundup® weed control product like Roundup® Ready-to-Use Weed & Grass Killer III with Sure Shot® Wand from your favorite retailer, you're not just buying a weed spray. You're buying a brand that's been used to fight weeds successfully in landscapes and other outdoor areas for over 40 years.

So what's the secret behind all of this success? It's simple: the Roundup® ingredients. Here's a quick review of the key ingredients in Roundup® Ready-to-Use Weed & Grass Killer, along with some science stuff about how it works.

To start, Roundup® Ready-to-Use Weed & Grass Killer is what's known as a non-selective herbicide. That's just a fancy way of saying it controls a wide range of weeds and grasses when used as directed. This includes the pesky broadleaf and grassy weeds you find in your garden beds and landscape areas.

The main active ingredient in Roundup® Ready-to-Use Weed & Grass Killer is glyphosate (pronounced GLY-pho-sate). Glyphosate is the one of the most studied herbicide on the planet, and is approved for use in the U.S. and many other countries all around the world.

Here's how it works: When glyphosate is applied to a weed, the weed absorbs it. It travels through the plant all the way down to the root, gradually stopping weed growth. Soon, the weed's leaves wilt, its roots die, and the entire weed withers to the ground. Over time, any glyphosate not absorbed by the weed breaks down into the soil as naturally occurring substances like carbon dioxide, nitrogen, and phosphate.

The other active ingredient in Roundup® Ready-to-Use Weed & Grass Killer is pelargonic acid, which allows results to appear quickly. This is a naturally occurring fatty acid that is found in many species of plants and animals, but it can also be used as an herbicide. When applied to a weed, pelargonic acid (like other fatty acids) lowers the internal pH of plant cells, which causes cell membranes to break down and leak. The result? The weed dies. Pelargonic acid works on contact, so it only affects the parts of the plant that it directly touches.

Now you know the active ingredients, backed by science, found in Roundup® Ready-to-Use Weed & Grass Killer. And when you know what's in what you're using – and why it's in there – you can use it with confidence. So, go on out there and tackle those weeds! (Just be sure to read and follow all label directions.)