Are Pre-Emergent Herbicides Safe Around Dogs?

Signal Words on Labels

• Most of the chemicals used in pre-emergent herbicides are considered to have a low toxicity level, and when used properly they are considered safe. A quick way to quickly assess the toxicity level of the weed killer you have chosen is to look for one of the signal words on the label: Caution, Warning or Danger. Herbicide labels with the word "Caution" are considered to have a low toxicity, whereas those labeled "Danger" have a higher toxicity level.

General Application Guidelines

• When applying a herbicide, the label will advise you to wear rubber gloves, long-sleeve shirt and long pants, socks and shoes. The key to protecting your dog from the herbicide is following the same concept – do not let your dog come in contact with the chemical. This means you will need to keep the pet off of the treated area until it is completely dry, normally 12 to 24 hours. Always read the label, however, to see how long it should take for the product to dry and be absorbed into the ground.

How Dogs Ingest Herbicides

• Pre-emergent herbicides, unlike post-emergent herbicides, need water for activation -- so the chemical is either sprayed or the lawn is watered after granules are dispersed. If the dog is allowed on the lawn before the chemical is dry, the animal will absorb the chemical through its paws and subsequent licking of paws or grass. Dogs are also prone to rolling in grass, which can cause them to absorb the chemical through their skin -- most herbicides are listed as skin irritants. In addition, they can ingest the chemical by playing with toys left in the lawn during application.

Safety Considerations

• If your dog only uses a portion of your lawn, consider not treating that area to protect the dog from any potential exposure. You can also try nontoxic alternatives for weed control. These include killing weeds with boiling water, vinegar, pulling weeds by hand or applying corn gluten meal to your yard twice a year. Lastly, if you suspect your dog has ingested a herbicide, contact your veterinarian immediately. Some signs of poisoning include vomiting and diarrhea.