My back yard is bordered by some very dense shrubbery and brush, which is a fertile breeding ground for creepy crawlies. With this stuff I'm able to create a cordon which keeps the bugs out of the yard and away from the house. As others have noted, you do have to replace it when it rains. I don't see this as a huge problem, however, as it really goes a long way. I estimate I can probably get a couple of dozen treatments from the one bag. A good product, especially if you have pets or small children and don't want to expose them to dangerous poisons.