Can this product be harmful to dogs if digested?

Thank you for your inquiry! Your pets are safe to enter a Preen Mulch with Extended Control area once it has thoroughly dried from the first rain/watering. This product contains a very small amount of the herbicide and we've never had a complaint regarding pet injury from dermal contact with this product. However pets must be kept safe from ingesting any herbicide, insecticide or fungicide. If you feel your pet would chew on the mulch then we do not recommend putting it down.