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President / Co-Founder

Jared Abrojena is the President and Co-Founder of Academy Trained. A Certified Arborist and internationally recognized competitor, Jared is a past ITCC World Champion and NATCC Champion. His leadership and expertise continue to inspire arborists across the industry through education, mentorship, and advanced training initiatives.

The most immersive tree industry community and training platform. Built by experts for professionals to raise standards in safety, skill, and innovation.

Professor of Forestry

Dr. John Ball is recognized as one of the tree care industry’s foremost experts on safety and arboriculture. As a Professor of Forestry at South Dakota State University, he teaches courses in arboriculture, forestry, and emergency technician training. In addition to his academic role, Dr. Ball serves as the campus arborist and Forest Health Specialist for the South Dakota Department of Agriculture.

His expertise bridges science and field application, focusing on improving safety standards, professional training, and emergency response in the arboricultural industry.

Credentials:

• Ph.D. in Forestry
• Board-Certified Master Arborist (BCMA)
• Certified Treecare Safety Professional (CTSP)
• Advanced Emergency Medical Technician (EMT)

Owner

Paul Biester, CTSP, founded Tree Awareness Inc. in 1993 and has been leading the company ever since. Before becoming a business owner, Paul worked as a climber, foreman, and sales representative for a small local company, where he developed his skills and passion for arboriculture.

Earlier in his career, Paul worked in furniture sales, where he discovered his interest in the art of selling and building relationships — an experience that shaped his lifelong philosophy on communication and customer service. Over the past three decades, he has refined his expertise through continuous learning, trade seminars, and books on sales and leadership. Today, Paul is passionate about sharing insights on effective sales strategies and relationship-driven business practices within the tree care industry.

Beyond his professional accomplishments, Paul is a devoted husband to his wife Rayna of 26 years, and a proud father to three children — Mikaela, Madison, and Mason. His deep commitment to both his family and the arborist community continues to define his approach to business and life.

Credentials:

• Teufelberger Ambassador
• CTSP
• Arborist, Certified Tree Worker
• TCIA Instructor
• HSI Level 2 Instructor

Chief Executive Officer

Years of Experience: 25

Responsibilities: Overall organizational and operational strategy, legal compliance, team professional and cultural development, risk management, and strategic planning through the NATS Advisory Board.

Credentials:

• AS in Arboriculture, Stockbridge School
• BS in Urban Forestry, University of Massachusetts – Amherst
• OSHA and ANSI SME Qualified Lead Instructor / Facilitator

Jamie Chambrelli has over 20 years of experience in the tree care industry, beginning his career as a production climber and rising to become a respected leader in safety and training.

He is a TCIA Certified Treecare Safety Professional (CTSP) and a Connecticut Licensed Arborist, recognized across the industry for his commitment to advancing safe practices and professional education in arboriculture.

Field Safety Supervisor / Trainer

Korey Conry has been part of the tree care industry for nearly five years, currently serving as a Field Safety Supervisor and Trainer at Mountain F Enterprises. His passion lies in cultivating a strong safety culture by training and onboarding new hires with an emphasis on awareness, skill, and responsibility.

Korey is a certified Utility Arborist through the ISA, TRAQ qualified, an ATSSA Flagging Instructor, AHA CPR Instructor, and OSHA Authorized Trainer. His diverse background includes experience as a wildland firefighter and emergency room technician.

When not in the field, Korey can often be found outdoors under a Blue Oak in Northern California, turkey hunting or adventuring with his son, Karter—often in epic “dinosaur battles.”

Arborist & Instructor

Kyle Donaldson is a well-traveled arborist and instructor who dedicates much of his time to training other arborists and utility engineers in advanced rescue techniques, emergency response, technical rigging, and chainsaw operation. He specializes in teaching climbing and comprehensive safety practices for industrial athletes.

With a passion for both education and fieldwork, Kyle has built a reputation for excellence in arboricultural training and performance. His skill and dedication earned him the title of 2019 New England Chapter ISA Tree Climbing Champion.

Dr. Ed Gilman is the author of “An Illustrated Guide to Pruning“, arguably the most complete and accessible reference on tree pruning in our industry. This comprehensive text has helped to inform countless professional arborists and tree surgeons on the best practices of training, trimming and pruning trees.

Dr. Gilman worked and taught at the University of Florida for over 30 years, publishing over 120 scientific papers. As a professor of Urban Trees and Landscape Plants in the Department of Environmental Horticulture, he worked with arborists, consultants, landscape contractors, growers, urban foresters, planners, landscape architects and others engaged in tree selection, growing, planting and management issues. His research included tree pruning, anchorage, roots, irrigation, and fertilization. Professor Gilman also did extensive research into the use of proper training and pruning to help reduce the damage to mature trees in severe wind events, i.e. hurricanes, etc.

He retired from academia in the summer of 2016 but remains actively involved with ISA Florida and with the ANSI Pruning Standards committee. He is particularly interested in the education of commercial arborists..

Heli-Ax is a company specializing in providing solutions for the Urban Forestry, Logging/Forestry Sector.

President and Chief Operating Officer

JIM INGRAM, Registered Consulting Arborist, Board Certified Master Arborist, is President and Chief Operating Officer for Bartlett Tree Experts, managing a $570,000,000 company with 22 divisions and 191 office field operations with 3,300 teammates in the US, Canada, the United Kingdom, and Ireland. Jim likes to recruit, develop, and guide senior managers who oversee private, public, commercial, and government sectors of the tree care business. Jim’s mantra is “The last person hired is the most important.”

Jim is a past Instructor of both Forest Science and Counseling at Penn State. He has been the past president of The Cape Cod Landscape Association, Cape Cod Horticultural Society, American Society of Consulting Arborists, and New England Chapter of the International Society of Arboriculture (ISA). He has served as the ISA’s Certification Board Chair and Chair of the Council of Tree and Landscape Appraisers.

Over 42 years, Jim has authored numerous publications and given over 850 lectures and workshops. He has been awarded the Pennsylvania Forest Academy Award, ISA Award of Merit, Cape Cod Landscape Association Legacy Award, Penn State Centennial Fellows Award, and Penn State Volunteer Award.

Heli-Ax Instructor

Heli-Ax is a company specializing in providing solutions for the Urban Forestry, Logging/Forestry Sector.

MAA Professor of Arboriculture

Brian Kane, Ph.D. is the Massachusetts Arborists Association Professor of Arboriculture at the University of Massachusetts – Amherst.

He is an ISA Certified Arborist who began dragging brush in 1988 and also holds the ISA’s Tree Risk Assessment Qualification (TRAQ).

Brian has written numerous scholarly and trade articles and has presented internationally on the mechanical aspects of tree work.

He is co-author on the 3rd editions of the ISA’s Tree Risk Assessment Manual, Best Management Practices: Tree Risk Assessment, and Best Management Practices: Support Systems. He is also writing a book on arboricultural biomechanics.

Heli-Ax Instructor

Heli-Ax is a company specializing in providing solutions for the Urban Forestry, Logging/Forestry Sector.

Co-Owner / Lead Instructor

Years of Experience: 25

Bear LeVangie is a trailblazer in arboriculture and tree climbing education, serving as Co-Owner and Lead Instructor of the Women’s Tree Climbing Workshop®. With over 25 years of experience, she has combined her deep technical expertise with a passion for empowering women in the tree care industry.

Credentials and Achievements:

• Bachelor’s Degree, University of Montana
• ISA TRAQ Certified Arborist
• Connecticut Licensed Arborist
• American Red Cross First Aid / CPR / AED Instructor
• Petzl Competent PPE Inspector
• Yoga Alliance Certified Instructor (250 hrs)
• Massachusetts Qualified Tree Warden
• Arborist Rope Splicer
• Past President, New England ISA
• Past Champion: NE-ISA TCC, CT TCC; Competitor: ME, NH, NY, ITCC
• Licensed Pesticide Applicator (MA, CT, NY)

Owner & Co-Founder

Melissa LeVangie Ingersoll is a passionate educator, arborist, and industry leader who has spent nearly three decades in arboriculture. She loves sharing her knowledge of trees and climbing, helping others build confidence and technical skill at all levels—from beginner to expert.

As the Owner and Co-Founder of the Women’s Tree Climbing Workshop®, Melissa also serves as a lead instructor, website designer, and head of marketing. Her approachable teaching style and technical mastery have made her one of the most respected figures in the field.

Qualifications & Achievements:

• University of Massachusetts Alumna
• ISA TRAQ Certified Arborist
• ISA Certified Climber Specialist
• American Red Cross Instructor
• Past President – New England Chapter, ISA
• Past President – Massachusetts Tree Wardens & Foresters Association
• Arborist Rope Splicer
• Petzl PPE Qualified Inspector
• Past Tree Climbing Champion – Connecticut, Maine, New England ISA, New Hampshire, and New York
• Former ITCC Competitor

Instructors

Mission: To empower people to live and work safely, create positive impact, and become the best version of themselves by inspiring a culture of safety through leadership, sustainability, and integrity.

At NATS, our mission reflects the heart of who we are — as individuals, as a company, and as industry partners. By engaging personally with our clients, we deliver tailored training and educational programs that improve safety and efficiency in the workplace. Our team shares knowledge, tools, and resources designed to elevate industry standards and promote safety across all sectors we serve.

Through collaboration and partnership, we raise awareness and ensure compliance with best practices and regulations, helping teams and organizations thrive safely and sustainably.

Ultimately, our goal is simple yet vital: to ensure that everyone returns home safely at the end of the day.

Instructors

Our mission at NJ Crane Expert is to equip crane operators and arborists with the hands-on skills and safety training they need to succeed in fast-paced, high-risk environments. With decades of industry experience, our founder and lead instructor, Hans Tielmann, understands the unique challenges and dangers faced on job sites—especially in the arborist and construction sectors. That’s why every training course we offer emphasizes OSHA compliance, real-world scenarios, and safety as the top priority.

Heli-Ax Instructor

Heli-Ax is a company specializing in providing solutions for the Urban Forestry, Logging/Forestry Sector.

Plant Healthcare Director

Phil Perron graduated from the University of Vermont with a degree in Forestry in 2000. He joined Hartney Greymont in the fall of 2000 and worked as an IPM technician for eleven years before becoming the Plant Health Care manager for a satellite office in 2011. In 2014 he joined Barrett Tree East in Medford Mass and is currently the director of the Plant Health Care Department.

Kristoffer Rasmussen is a respected leader in the Tree Care Industry, known for his dedication to arborist safety, training, and company development. With a background as a municipal arborist, he brings valuable insight to his roles as a Certified Treecare Safety Professional, TCI Accreditation Auditor, and CPR/First Aid instructor. Kristoffer helps tree care companies meet high standards through assessments, training, and accreditation. His passion for arboriculture and urban forest preservation makes him a trusted voice in the field.

Brick Reilly is a 43-year-old tree-climbing arborist from Springfield, New Jersey. He is a NJ Licensed Tree Expert, ISA Certified Arborist, ISA Certified Tree Specialist, and is employed by a New Jersey municipality.

He is a passionate steward for nature and a firm believer that we are not separated from nature, but have simply forgotten that we are a part of it. Brick is a devoted practitioner of wellness and believes that longevity in the arborist industry is possible. Building, movement, and stillness are the three cornerstones of his approach.

Brick is also a tree-climbing competitor who loves to invest time into performing his best. His favorite event is Aerial Rescue, as it is both a highly technical challenge and deeply personal—especially given that he is deaf and must adapt creatively to succeed.

Born deaf and having received a cochlear implant at the age of 22, Brick has always had to find innovative ways to communicate and build trust with coworkers. With 22 years in the arborist industry, his experiences have shaped a personal philosophy he lives by: “Always a student.”

Safety and Training Specialist (Bilingual)

Years of Experience: 20
Joined NATS: 2017
Where I’m From: Puerto Rico
Why I love working in this industry: The fact that my job is sharing and exchanging knowledge of the tree industry and working on trees with people that live the same lifestyle that I do, makes every day at work, a rewarding experience. All these years working in trees had shown me that the industry itself behaves as trees in the forest. We are somehow all connected and we all support each other.

Credentials:

•First Aid/CPR Certification
•Consulting Utility Forestry Safety Professional
•OSHA 30-Hour General Industry Training with Arboricultural Emphasis
•ISA Certified Arborist
•Chainsaw Train the Trainer
•Electrical Hazard Awareness Training
•B.A. Physical Education, University of Puerto Rico, Cayey Campus

Chief Executive Officer

Mark Sedgley is an accomplished SaaS executive passionate about building companies and cultures that serve teams, customers, and communities with purpose. Over the last 20 years, he has founded and scaled software companies, stepped in as CEO to lead through founder transitions, and successfully executed nine acquisitions.

Today, as CEO of Granum, he is focused on driving sustainable growth in the green industry through intuitive, connected software. Beyond work, Mark values his 30-year marriage to his high school sweetheart, Dorota, and raising their three children—Jake, Ash, and Kaia.

Instructor & Climbing Arborist

Rebecca Seibel is a veteran climbing arborist with over 25 years of hands-on experience in the field. Her teaching and leadership style are rooted in practicality, empathy, and authenticity — blending clear communication with deep compassion for both people and nature.

Rebecca’s core values — Nature, Competency, and Creativity — guide everything she does. She is passionate about showing others what it feels like to be part of a safe, fun, and highly competent crew, helping foster confidence and connection in every student she mentors.

When she’s not teaching or climbing, Rebecca enjoys traveling with her family, spending time with her horses, and seeking adventure in harmony with her guiding principles — in short, living in alignment with her values.

Woody Ornamental Entomology Specialist

Tawny Simisky is a Woody Ornamental Entomology Specialist with the University of Massachusetts Extension’s Landscape, Nursery and Urban Forestry Program. In her role, she develops resources and educational programs for landscape professionals, arborists, and grounds managers while providing entomological and diagnostic support to the UMass Plant Diagnostics Lab.

Before joining UMass, Tawny worked with the Massachusetts Department of Conservation and Recreation’s (DCR) Forest Health Program, contributing to the eradication of the Asian longhorned beetle and monitoring of forest pests such as the emerald ash borer and hemlock woolly adelgid across the state.

She earned her M.S. in Ecology and Environmental Science with a focus on Entomology from the University of Maine, Orono, where her research centered on biosurveillance for the emerald ash borer using the native, non-stinging wasp Cerceris fumipennis (the smoky-winged beetle bandit). She also holds dual B.S. degrees in Biology and Environmental Science from Westfield State University in Westfield, Massachusetts.

Owner

Hans Tielmann is a tech-savvy graduate of Fairleigh Dickinson University and a licensed tree expert with over 20 years of professional experience. He is the founder of NJ Crane Expert and serves as the company’s lead crane instructor for NCCER crane certification classes.

Known as the “Tree Tactician,” Hans excels at planning and executing tree removal projects in high-risk environments and enjoys sharing his expertise with students. He is a passionate educator who promotes safe practices and effective techniques for arborists through the use of modern equipment and comprehensive strategy.

Credentials include:

• NCCER – Craft Instructor, Mobile Crane Operator, Practical Examiner & Proctor, Subject Matter Expert
• TCIA – Accredited Trainer and ISA Member
• LTE – Licensed Tree Expert #670 / Professional Witness
• CTSP – Certified Tree Care Safety Professional
• EHAP – Electrical Hazard Awareness and Prevention Qualified
• First Aid Certified

Owner

With over two decades of experience in the tree service industry, Joe Whitledge brings unmatched expertise and leadership to the arboriculture community. As the proud owner of Whitledge Tree Service, Joe has built a reputation for reliability, professionalism, and deep industry knowledge.

Under his leadership, Whitledge Tree Service has handled over 100 emergency tree removal claims in a single year. Beyond his company’s success, Joe has also mentored and assisted dozens of other businesses in successfully navigating insurance claims and achieving greater operational success.

Today, Joe continues to lead the way in emergency response education and training for tree care professionals nationwide.

Instructors

The Women’s Tree Climbing Workshop® started in 2009. It began from a frequently repeated question, “How’d you learn how to climb?” So, with an idea and an ask of fellow amazing women, what if we just build it, will they come?

The WTCW has developed more courses than just tree climbing. With an all-women led team, our focus is to provide women with the skills and knowledge they need to develop their skills with confidence and safety.

We are a passionate team who focus on the different styles of learning. We know what has worked for us personally to excel and want to share our paths, our challenges and our successes.

Our instructors approach teaching and coaching as they do their careers and off-time: with dedication, curiosity, intention, and fun.