
Cheryl Daniels
Angela Burdell
Davey Resource Group, Inc.
Kent, OH
Conduct of Research Report for NCHRP Project 14-47
Submitted November 2024

NCHRP Web-Only Document 429
Investigation of Tools and Technology for Roadside Vegetation Asset Management
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NATIONAL COOPERATIVE HIGHWAY RESEARCH PROGRAM
Systematic, well-designed, and implementable research is the most effective way to solve many problems facing state department of transportation (DOT) administrators and engineers. Often, highway problems are of local or regional interest and can best be studied by state DOTs individually or in cooperation with their state universities and others. However, the accelerating growth of highway transportation results in increasingly complex problems of wide interest to highway authorities. These problems are best studied through a coordinated program of cooperative research.
Recognizing this need, the leadership of the American Association of State Highway and Transportation Officials (AASHTO) in 1962 initiated an objective national highway research program using modern scientific techniques—the National Cooperative Highway Research Program (NCHRP). NCHRP is supported on a continuing basis by funds from participating member states of AASHTO and receives the full cooperation and support of the Federal Highway Administration (FHWA), United States Department of Transportation.
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The National Academy of Sciences (NAS) grants permission to reproduce written material in this publication for classroom and non-commercial purposes subject to the rights of any third parties and appropriate attribution. Permission is given with the understanding that none of the material will be used to imply NAS, TRB, AASHTO, APTA, FAA, FHWA, FTA, GHSA, or NHTSA endorsement of a particular product, method, or practice. For other uses of the written material, users must request permission from the National Academies Press.
DISCLAIMER
This material is based upon work supported by the FHWA under Agreement No. 693JJ32350025. Any opinions, findings, and conclusions or recommendations expressed or implied in this document are those of the researchers who performed the research and are not necessarily those of the Transportation Research Board; the National Academies of Sciences, Engineering, and Medicine; the FHWA; or the program sponsors.
The Transportation Research Board does not develop, issue, or publish standards or specifications. The Transportation Research Board manages applied research projects which provide the scientific foundation that may be used by Transportation Research Board sponsors, industry associations, or other organizations as the basis for revised practices, procedures, or specifications.
The Transportation Research Board, the National Academies, and the sponsors of the National Cooperative Highway Research Program do not endorse products or manufacturers. Trade or manufacturers’ names appear herein solely because they are considered essential to the object of the report.
The information contained in this document was taken directly from the submission of the author(s). This material has not been edited by TRB.

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Monique R. Evans, Director, Cooperative Research Programs
Waseem Dekelbab, Deputy Director, Cooperative Research Programs, and Manager, National Cooperative Highway Research Program
Christopher T. McKenney, Senior Program Officer
Sheila A. Moore, Program Associate
Natalie Barnes, Director of Publications
Margaret B. Hagood, Senior Editor
Kathleen Mion, Assistant Editor
Kris Gade, Pima County Department of Conservation Lands and Resources, Tucson, AZ (Chair)
James W Buck, New York State Department of Transportation, Hancock, NY
Mohab Hussein, New Jersey Department of Transportation, Ewing Township, NJ
Robert LaRoche, John Turner Consulting, Bowdoinham, ME
Ronaldo Luna, Saint Louis University, St. Louis, MO
Phillip Montoya, New Mexico Department of Transportation, Santa Fe, NM
Christa Schaefer, Wisconsin Department of Transportation, Madison, WI
Sarah Tamayo, Arkansas Department of Transportation, Little Rock, AR
Raymond G. Willard, Washington State Department of Transportation, Olympia, WA
Katherine A. Petros, FHWA Liaison
We would like to thank the Davey Resource Group staff who contributed to this project, including Keith Shane and Adrienne Watts, Rasor Communications and Marketing, who supported the project with formatting and survey distribution and analysis, and Untold Content, who supported the project with technical writing and review.
We would also like to thank each of the state DOTs that took the time to answer the survey questions. Finally, we extend our gratitude to the California Department of Transportation, Ohio Department of Transportation, Tennessee Department of Transportation, Washington State Department of Transportation, and Wisconsin Department of Transportation for participating in the case studies.
1.2 Structural and Vegetative Assets
1.3 Benefits and Detriments of Roadside Vegetation Assets
1.4 Roadside Vegetation Asset Management Funding Barriers
1.5 Research Objectives and Scope
2.1 Literature Review and Nationwide Surveys
2.3 Work Plan for the Guidebook
2.4 Interim Report and Technical Memorandum
CHAPTER 3 Findings and Applications
CHAPTER 4 Conclusions and Suggested Research
Abbreviations, Acronyms, Initialisms, and Symbols
Appendix C: Nationwide Survey Results
Appendix D: Case Study Questions
NCHRP Web-Only Document 429 contains the Conduct of Research Report for NCHRP Project 14-47 and accompanies NCHRP Research Report 1155: Tools and Technology for Roadside Vegetation Asset Management: A Guide. Readers can read or purchase NCHRP Research Report 1155 on the National Academies Press website (nap.nationalacademies.org).