.50% Strychnine alkaloid     99.5% (looks like oats or maybe barley)  I bought over the internet.  No questions asked.  I use a long spoon to put 2 spoon full down the hole.  Root ball in hole. Dirt on top.  Or With no root ball or dirt.  I use a long spoon so the birds do not get at it. 

Works good for us. 

Auto shop friend was shocked that I could have that shipped by UPS or maybe it was the mail.  I forget.  He says he can't even get oil shipped because it is a "hazard waste".  Crazy America.