Atrazine is a very common product that you find in weed and seed. It is easy to apply and been around forever.  You will find it in granular and liquid form.  The problem with atrazine is that it leaches pretty bad.  When you get a lot of rain like we have had lately, it pretty much will be washed out and rendered infective.  If you start seeing less than favorable results and maybe you or your provider put it out earlier this spring, it is probably because it has not been washed out and is no longer working.  This is why using a good quality product is going to be your better option.  Just something to keep in mind. If you have any questions please let us know!