The Tree Climbers' Guide, 4th Edition, by Sharon J. Lilly and Alex K. Julius, is the updated primary study resource for ISA Certified Tree Worker and Aerial Lift Specialist exams. Released in 2021, this edition features over 270 illustrations and covers modernized techniques, including Moving Rope Systems (MRS) and Stationary Rope Systems (SRS). For more details, visit the Tree Climbers' Guide,4th edition

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