According to the people at lowes they are required to list it as a blend if it contains other woods and to list the other woods present. I also called the manufacturer number listed on the bag and they said it was 100% cypress. Of course i'm sure multiple types are processed on the same equipment, and I'm sure there are potential trace amounts of other materials. The pesticide and fertilizer aspect is definitely an improtant consideration. I will be checking with the manufacturer on that. Of course as you point out they are not listed as pet safe so I'm sure there is no legal liability for their claims. Ultimately the cost savings may not be worth it.