Ortho® Orthene® Fire Ant Killer1


Ortho® Orthene® Fire Ant Killer1

Ortho Orthene

What We Like:

  • Sturdy, recyclable container
  • Kills the queen and destroys the mound
  • Should not be watered-in
  • Built-in seal opener

What We Don't Like:

  • Powder can drift easily
  • Very strong odor

Ortho Orthene Fire Ant Killer1 is an outdoor mound treatment that kills fire ants fast and destroys the mound and queen.

In This Review:

Many fire ant experts say the best way to get rid of fire ants is a two-step approach that treats your entire yard and targets individual fire ant mounds. Fire ants relocate frequently, so even treated yards are subject to new mounds as fire ants migrate or expand their territories. That's where fire ant killers, including those that treat just mounds, come into play.

Ortho markets Orthene Fire Ant Killer1 as "Step 1: Kill the Mound," the first part in the manufacturer's two-part fire ant treatment program. But you can use it as a mound treatment on its own. This fast-acting product is intended to treat visible fire ant mounds as they appear, killing mounds and fire ant queens. The dry powder formula needs no watering-in, so application is relatively quick and easy.

Performance: Works fast, kills the queen

Unlike some dual-purpose products, Ortho Orthene Fire Ant Killer1 is an outdoor fire ant treatment designed exclusively for mounds. The product's active ingredient is acephate, widely used in fire ant killers to kill these pests by contact. As with other types of contact killers, this product only kills fire ants that contact the product directly or make indirect contact through treated ants.

Many contact killers require you to water the treated area right after application to release the active ingredients and move them through the soil. But Ortho Orthene Fire Ant Killer1 is a powder meant to stay dry, not get watered-in.

The product pledges to kill fire ants within 60 minutes. It also kills fire ant mounds and queens — the only way to kill the entire fire ant colony. A satisfaction guarantee backs those promises.

Application: Forget watering-in, but beware of breezes

Because Ortho Orthene Fire Ant Killer1 is a dry powder formula, be extra careful when opening and using the product. The instructions warn against shaking the container, which has a neat seal opener built into the cap. Just follow the instructions on the lid, turn the cap upside down, and it cuts the inner seal — without the powder going airborne. When you finish treating, the cap screws back on the rigid plastic container easily.

Because you shouldn't water-in this product after application, it's more convenient than many others. It's also easier to avoid disturbing the ants and causing relocation — or risking bites and stings. But the catch is that the dry, whitish powder can drift easily unless the air is completely calm. Plus, this product has a strong, unpleasant smell.

Many mound products use a set application for all mounds, but Ortho Orthene Fire Ant Killer1 recommends different rates based on mound size. A mound less than 4 inches in diameter takes just 1 teaspoon. Mounds greater than 12 inches in diameter take 3 tablespoons. (The label has a nice reminder that 1 tablespoon equals 3 teaspoons.)

Treat new mounds by sprinkling the dry powder over the mound. Always use a measuring spoon devoted to pesticides. Never return a treatment spoon to the kitchen, no matter how well you clean it.

For best results, apply this powder contact killer when ants are active. That's typically early morning and late afternoon or early evening during warm, moderate weather. Fire ants move deeper in soil during hot, dry conditions, leaving this product less effective in making the contact needed to kill fire ant colonies.

Because this product's effectiveness relies on staying dry, do not apply this when dew is heavy or rain is on the way. As with most fire ant killers, keep this product away from vegetable gardens or areas with other edible crops.

Pets and Children: Reenter treated areas after the dust has settled

When you treat an area for fire ants or any other pest, protect your pets and family by clearing the area during the application. Then follow the label instructions for when it's okay for you and your pets to reenter the area. With Ortho Orthene Fire Ant Killer1, wait until the dust from the powder settles.

Competition: Ortho® Orthene® Fire Ant Killer vs. Over'n Out!® Advanced Fire Ant Killer Mound Eliminator

Ortho Orthene Fire Ant Killer1 and Over'n Out! Advanced Fire Ant Killer Mound Eliminator are both mound treatments that work by contact. Only fire ants that come in contact with treated ants or the product are killed. The Ortho powder comes in a rigid plastic container, while the Over'n Out granular product comes in a resealable bag. Both products are dry and ready to use.

The Ortho powder product should remain dry after application. While we like the convenience of not watering-in, the powder drifted slightly even though it was close to the ground. We didn't like that. The Over'n Out granular product has to be watered-in to release the active ingredients into the mound. But the extra step makes sense to get the contact killer underground and into the colony.

Ortho Orthene Fire Ant Killer1 label promises to kill within 60 minutes and kill the queen and destroy the mound, but it's not clear if the one-hour time frame applies to the queen. Over'n Out! Advanced Fire Ant Killer Mound Eliminator pledges to kill the mound in 15 minutes and kill the queen within 24 hours. Both products come with guarantees, but Over'n Out also promises up to six months of control. The Ortho Orthene Fire Ant Killer1 label doesn't promise any long-lasting control beyond the initial application.

Because of the differences in product forms and residual protection, comparing fire ant killers is challenging. The Ortho product seems relatively expensive at $11.47 for 12 ounces,but the product says it will treat 162 mounds. That's only small mounds less than 4 inches in diameter, but it works out to just 7 cents each. Treat mounds larger than 12 inches across, and the per-mound price jumps to about 64 cents.

The 4-pound bag of Over'n Out product costs $10.54 for about 16 treatments, based on the recommended application rate. One application can last six months, but that's about 66 cents per mound. So, depending on the size of the mounds you're treating, the Ortho product's per-mound price may win on value.

Conclusions: Convenient, fast-acting mound treatment

Ortho Orthene Fire Ant Killer1 is a convenient contact mound killer that doesn't require watering-in to kill the mound and the queen. It costs more than other contact killers, but the per-mound price translates to a good value on smaller mounds — if you don't mind the powder and the smell.

The opinions represented in this article are the author's. However, the author has been paid by the owner of this website, Central Garden & Pet Company.