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Arborist Site Discussion Group
A loose affiliation of volunteer tree working professionals that discuss the needs of tree care within the industry and answer questions for the general public.
http://www.arboristsite.com/
European Arboricultural Council
A forum for arboricultural organizations in Europe to liase on research and education in tree establishment and improvement of working practices.
http://www.eac-arboriculture.com/
International Society of Arboriculture
Arboriculture On-line was developed to assist tree care professionals in developing and maintaining effective plant health care programs. Includes an extensive collection of urban forestry links.
http://www.isa-arbor.com/
National Arborist Association
The trade association of commercial tree care businesses. Site has information (for consumers and for professionals) and links on tree care practices and standards.
http://www.natlarb.com/
The California Arborists Association
Membership information, details and timetables of activities and workshops.
http://www.cal-arb-association.com
