The system for injecting a systemic treatment liquid into trees and similar plants includes a plurality of substantially identical injector nozzles, each of which is insertable into one of a plurality of circumferentially spaced injector holes in the tree, a plurality of substantially identical ...http://www.google.com.au/patents/US4144673?utm_source=gb-gplus-sharePatent US4144673 - System and method for introducing systemic treatment liquids into trees and similar plants 
