Staff & Board


Cristina Bowerman

Executive Director

Cristina has worked in the nonprofit sector for the past 25 years. She spent 15 years with 501(c)(3) charitable organizations and 10 years with 501(c)(6) trade associations. A native Floridian, she attended the University of Central Florida, where she earned her master's in Nonprofit Management and bachelor's in Advertising and Public Relations. She is a Certified Association Executive with the American Society of Association Executives.

She recently relocated to Tigard, OR with her husband and fur babies. A tree enthusiast, she loves being outside to hike and just spend quiet time in nature. She is excited to be joining Team PNW-ISA and looks forward to learning more about the amazing trees that inhabit the Pacific Northwest region.

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Margo Thorp

Education Program Coordinator

Margo graduated from Western Washington University with a Bachelor of Arts in Education, focusing on science education in the K-8 classroom. She has worked as Coordinator and Educator with the UW – Friday Harbor Labs Science Outreach Program and as Program Coordinator with the University of Washington - Professional and Continuing Education.

Margo participated in Horticulture courses at Edmonds Community College with a focus on arboriculture, pruning, and tree care. She also spent a year working as an intern with the Elisabeth C. Miller Botanical Garden in the Seattle area. Outside of work Margo enjoys skate skiing, pottery, trail running, boating, and gardening.

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Sharon Korte

Member Services Coordinator

Image of Sharon Korte, a white woman with blond, shoulder-length hair, wearing a black sleeveless shirt. She is standing in front of some tall flowers and a white fence.

Sharon Korte joined the  Pacific Northwest chapter as the Member Services Coordinator in June 2019. Sharon has 7+ years of experience with the international Society of Arboriculture and held roles such as Credentialing Manager and Customer Relations Manager. She has a solid foundational knowledge of membership, credentialing, and arboriculture programming.
Sharon is an avid gardener with a love for flowers. She is a self-proclaimed book-a-holic - reading upwards of 50+ books per year.

Sharon lives in Tuscola, IL with her husband Chris and their two American Eskimo dogs, Crystal and Roxxie.

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Board of Directors

Philip Bennett


Urban Forester, City of Snoqualmie; City Arborist, City of Clyde Hill, in Snoqualmie, WA

Phil is a graduate of the University of Wales, Aberystwyth with a BA in English literature, and is an ISA Certified Arborist, Municipal Specialist, qualified tree risk assessor and former environmental educator. Phil is actively engaged in the disciplines of arboriculture: Planting,mulching, pruning, treating diseases, climbing, and removing trees. Phil is convinced that not only is this the best job in the world, it’s also making the world a better place. Read More About Philip Bennett

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Charles Ray

President Elect

Urban Forester with the City of Vancouver, in Vancouver, WA

Charles Ray is the Urban Forester with the City of Vancouver, Washington. Charles is a graduate from the Ohio State University with a Bachelor of Science in Natural Resources. He is certified through the International Society of Arboriculture as an Arborist and Municipal Specialist. He has worked in both the municipal and commercial arboriculture fields before starting with the City of Vancouver in 2001. Read More About Charles Ray

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Ian Scott


Davey Resource Group, in Shoreline, WA

Ian Scott, a white man with dark hair, a salt-and-pepper beard and glasses.

Ian Scott is a Regional Manager and urban forestry specialist based out of Shoreline, Washington. He has served clients as part of the Davey Resource Group team throughout the Western U.S. and Canada since 1998. He works with many cities to develop urban forest management consulting solutions, deliver urban tree inventories, and provide urban tree canopy assessments.  Ian has a Bachelor of Science degree in Forestry and Environmental Management from the University of New Brunswick, Canada. He is an ISA Board Certified Master Arborist with a Tree Risk Assessment Qualification. He is a 2009 graduate of the Municipal Forestry Institute. Read More About Ian Scott

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Kris Josey


ArborCare Resources, Inc., in Hailey, ID

Kris Josey graduated from University of Colorado, Boulder with a BS in Accounting in May 1989. Upon graduation she worked as a staff accountant with Coopers & Lybrand’s Denver, Colorado office from June 1989 to November 1992. She obtained her CPA license in 1992. Later that year, she moved to Idaho and worked in a local accounting office until June 1996 when she left public practice to be a stay at home mom with her 2 young sons. In early 1997, she and her husband, Bill, combined her business/accounting knowledge with his tree care knowledge to start their family business ArborCare Resources, Inc.  Kris continues to be actively involved with the management of the business. Read More About Kris Josey

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Anna Heckman

Member Services

Anna’s education in forest ecology, and urban horticulture led her to a career in natural area management and arboriculture.  Her career has grown her passion for understanding research and bridging the communication gaps between science and management.  Anna has over 15 years of service in government employment ranging from a backcountry field technician to a plant ecologist, vegetation manager to an urban forester.  Anna recently found a great fit applying her skill set as a consulting arborist with Urban Forestry Services Inc. Read More About Anna Heckman

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Kurt Fickeisen


Symbiosis Tree Care LLC, in Seattle, Washington

Kurt is the owner of Symbiosis Tree Care in Seattle Washington and has worked in arboriculture since 1989. While most work takes place in the greater Seattle area, Kurt spent three years working for a tree service in Boulder Colorado.

Work in these areas has expanded his knowledge of how tree growth patterns can vary from region to region. The primary focus of work is as a Consulting Arborist. Read More About Kurt Fickeisen

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Gregg Staniforth

Continuing Education Director

City of Victoria, in Victoria, BC

Since 1999, Gregg has committed his career to the management and preservation of urban trees in the provinces of Quebec and British Columbia.

He completed a Bachelor’s degree in Forest Science from the University of
British Columbia followed by a Master’s of Science in Arboriculture and
Urban Forestry from the University of Central Lancashire. Gregg is ISA Certified and Tree Risk Assessment Qualified. Read More About Gregg Staniforth

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Corey Bassett

Public Outreach & Engagement Director

PhD Student, University of British Columbia, Faculty of Forestry, in British Columbia

Corey Bassett is a PhD Student researching urban forest management at the University of British Columbia, Faculty of Forestry.

Like many others, Corey entered the field of arboriculture and urban forestry accidentally. She had never even heard of the word “arboriculture” prior to applying for her first job, the Urban Forestry Internship at the Morris Arboretum of the University of Pennsylvania. As Public Outreach & Engagement Director of PNW-ISA's Board, she hopes to create paths for early career professionals and students entering the industry, as well as serve as a link between PNW-ISA and the research community.
Read More About Corey Bassett

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Mike Oxendine

Governance Director

Ashland Parks and Recreation Commission, in Talent, Oregon

Mike has called Oregon home since 1985 and lives in the small community of Talent. He is an ISA certified Arborist (PN 7681A), licensed Oregon Landscape Construction Professional (OLCB #15598), and holds an Associates in Science degree, working towards a Bachelors in Innovation and Leadership, and plans to attain a Masters in Urban Forestry.

He loves to serve others, and works full time as the Parks Superintendent for the Ashland Parks and Recreation Commission.  He serves not for profits in his current board positions on the Post Growth Institute Board of Directors, Oregon Community Trees Board of Directors, and PNW ISA Board of Directors. Read More About Mike Oxendine

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John Hushagen

ISA Council of Representatives

John has been an arborist since 1980 and a member of the ISA since 1984.  In 1987 he completed his Masters’ of Science in Urban Horticulture and co-founded Seattle Tree Preservation, Inc. He owned and operated this tree care company until its sale to Bartlett Tree Experts and his retirement in February 2018. He has been a certified arborist since 1992, and currently works part-time as a consulting arborist in the Seattle area.  He was elected to the PNW ISA Board in 1988 and served as vice president, president, and ISA representative until 1994.  After hiring the first paid chapter administrator in the early 90’s, and promoting the newly-minted Certified Arborist program, the growth of the PNW Chapter was phenomenal. Read More About John Hushagen

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Evan Sussman

TREE Fund Liaison

Sonshine Tree Care, in Stanwood, WA

Evan Sussman is the owner of Sonshine Tree Care in Stanwood, WA. Evan’s career in arboriculture began in the tropical climate of Hawai'i. In 2012 Evan moved to the Pacific Northwest.

Evan is an ISA Certified Arborist (WE-9274A), and ISA Qualified Tree Risk Assessor. He is actively involved in the furthering of the arboriculture profession in our chapter through community engagement, as a professional tree worker instructor, and in the development of apprenticeship programs. Read More About Evan Sussman

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