- The International Society of ArboricultureHereby Announces ThatHarrie VerbeekHas Earned the CredentialISA Certified Arborist ®By successfully meeting ISA Certified Arborist certification requirements through demonstrated attainment of relevant competencies as supported by the ISA Credentialing CouncilCaitlyn Pollihan CEO & Executive Director31 December 202626 September 2014DU-0012AExpiration DateCertification NumberIssue Date#0847 ISA Certified Arborist

The International Society of Arboriculture
Hereby Announces That
Harrie Verbeek
Has Earned the Credential
ISA Certified Arborist ®
By successfully meeting ISA Certified Arborist certification requirements through demonstrated attainment of relevant competencies as supported by the ISA Credentialing Council

Caitlyn Pollihan
CEO & Executive Director
31 December 2026
26 September 2014
DU-0012A
Expiration Date
Certification Number
Issue Date

#0847
ISA Certified Arborist
Harrie Verbeek
ISA Certification is a voluntary program that tests and certifies a professional’s achievement of a standard level of knowledge and skill in the field of arboriculture. When a professional becomes an ISA Certified Arborist, they should be recognized by their peers and the public as a tree care professional who has attained a generally-accepted level of knowledge in areas such as tree biology, diagnosis, maintenance practices, safety, and other subject and practice areas within the tree care profession as identified through periodic job task analyses.
Skills / Knowledge
- tree maintenance
- tree pruning
- pruning
- tree care
- tree diagnosis
- tree planting
- arboriculture
- tree management
- tree inspection
Issued on
September 26, 2014
Expires on
December 31, 2026
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