Why Hire an Arborist?: Information from the International Society of Arboriculture (ISA) on why you can feel confident when hiring an arborist to do your treework. This page also provides a great deal of information on various treecare issues.

National Arborist Association (NAA): "The NAA is a trade association of commercial tree care firms, established in 1938. Our association develops safety and education programs, standards of tree care practice, and management information for arboriculture firms around the world."

International Society of Arboriculture (ISA): The ISA's mission is "to foster a greater appreciation for trees and to promote the research, technology and practice of professional arboriculture."

New York State Arbortists, ISA Chapter: "The New York State Arborists, International Society of Arboriculture Chapter, Inc. is an association of professional arborists and educators that promotes public interest, fosters research and education in the care and benefits of trees, shrubs and their environment."