Learn More About the Underground System of Trees

Learn More About the Underground System of Trees

ISA offers a variety of educational materials and products to help arborists expand their professional knowledge and experience. Every month, the ISA will feature a product or group of products. In March, the ISA features Roots: A Field Guide for Identification by Kristin Moldestad and Olve Lundetræ.

Available in English for the first time, Roots: A Field Guide for Identification gives a unique insight into what the roots of different trees look like while explaining a previously little-described underground world.

This publication compiles roots from 45 different species of everyday European street and park trees and features photographs and descriptions of each example's anatomical characteristics, habits, and, in some cases, scent.

One of the authors, Moldestad, said the idea for this book came from an oak tree.

“The idea to collate this material in a reference book grew from a project we were involved in to preserve a large, old oak tree growing in a playground,” Moldestad said. “The oak was in a group with hazel, Norway maple, and birch, and the plan was to fell the other trees. Removing the soil near the oak revealed a dense network of roots, and it was impossible to see which roots belonged to which tree. A search of the literature and the internet did not provide any answers as to how to identify roots quickly and easily in the field or whether it was even possible. We lacked the knowledge necessary to determine the species of the roots in front of us, and so we decided to find out more.”

The book is practically oriented and aids readers in identifying roots in the field. It is a resource for professionals and for those who are simply curious about one of the essential parts of the tree—the underground system, where nutrients, water, and oxygen exchange happen, creating the basis for everything seen above ground.

“We hope it can help arborists in the field to become more proficient in identifying root species, potentially enabling them to preserve more trees,” Moldestad said. “[Additionally], we hope they gain increased knowledge about roots and realize that roots are just as diverse as leaves and branches in trees of different species.”

While this book focuses on street trees that are common in Europe, it may appeal to a broader audience as many of the species are planted as street trees in other temperate zones.

“Several tree species from the book are also found [outside of Europe],” Moldestad said. “The tree species are sorted by family, and there are some similarities within families/genera. It also provides valuable information on how to identify roots in the field and what to look for to discern differences.”

Purchase your copy today.


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