Center for Environmental Excellence by AASHTO CENTER HOME  
skip navigation
CEE by AASHTO Home | Compendium Home | Online Compendium Help | Recent Updates | Inquiries | FAQs | State DOT Links
About Best Practices | Comment on Best Practices | Suggest A Best Practice | Volunteer to Vet Best Practices
Printer Friendly Version Print This Page    
« Back to Chapter 8 | Go to Chapter 10 »
Chapter 9
Roadside Vegetation Management
9.0. Introduction

Transportation agencies manage approximately 12 million acres of land surrounding state, interstate, county, and municipal roads. [N] DOT roadside vegetation management involves a wide range of concerns including prevention of erosion and sedimentation control and spread of noxious weeds, in addition to transportation concerns and efficient use of resources to accomplish management objectives for the right-of-way. [N]

Today, ROW managers must be concerned with multiple use aspects of ROW management; multiple use concerns necessitate the development of plant communities that resist the invasion of woody plants, are aesthetically pleasing, provide food and/or cover for wildlife, and can be economically established and maintained. [N] In the name of safety, improved visibility and obstacle-free roadsides, roadside vegetation managers favor grasslands, which formerly covered more than half the U.S. [N] Once established, the native grasses save maintenance dollars over time, provide a self-reliant and hardy plant community, improve wildlife habitat, and protect the local character and natural heritage of a site. [N]

WSDOT's State Roadside Manual outlines some of the many functions vegetation contributes that add significant value to our environment, including: [N]

  • Vegetative MaintenanceTraffic calming
  • Stress reduction
  • Buffer or shade for pedestrian or park and ride facilities
  • Stream bank stabilization
  • Wetland mitigation
  • Water quality improvement
  • Water retention and smoother flows
  • Air pollution mitigation
  • Noise abatement
  • Wildlife habitat
  • Enclose, screen, expose, or blend
  • Visual quality, quality of life
  • Corridor continuity

Several years back, NCHRP 20-5, 33-04 surveyed a sample of state DOTs and identified erosion control as a primary concern in management of vegetation. Indiana, Minnesota, Texas, and Washington reported that their vegetation management activities were affected by stormwater management objectives. Florida, Illinois, Indiana, Maryland, Ohio, Texas, and Washington reported control of roadside fire starts as a concern addressed by their vegetation management practices. The use of native plants in construction or restoration of roadside vegetation patterns was mandated by policy or state laws in slightly more than 40 percent of the reporting states. The dollar value assigned to benefits of "environmentally sensitive" maintenance methods (i.e., mowing of brush verses spraying of brush) have been established by four of the responding states: Florida, Illinois, South Carolina, and Texas. The same valuation in regard to construction methods was identified by only Florida and Illinois. Connecticut, Illinois, Maine, Minnesota, Nebraska, Ohio, Pennsylvania, Texas, Utah, Washington, and West Virginia said that environmental impacts from long‑term sustainability were given consideration in construction of new roadside projects. [N]

The author performed a survey of DOT roadside vegetation managers in 2005 regarding their key considerations, obstacles, and priorities in vegetation management, particularly related to invasive species control. In turn, this input from practitioner leaders helped identify areas where best practice identification and sharing were most needed. Chapter 9 of AASHTO's Environmental Stewardship Practices Compendium has been totally revised as a result, in the attempt to fill some of those gaps. Detailed guidance on best practices is also provided in Chapter 4 on Construction practices, as so many of these can either promote or control invasives species. Of particular relevance in the latter are topsoil stockpiling, erosion and sedimentation control, and proper stabilization.

< back to top >
Continue to Section 9.1»
Table of Contents
Chapter 9
Roadside Vegetation Management
9.0 Introduction
9.1 Inventory of and Management for Rare Species and Sensitive Resources in the ROW
9.2 Growing Threats Drive Expansion of DOT Invasive Species Practice
9.3 Practices for Prevention of Roadside Infestations
9.4 Statewide Inventory of Invasive or Noxious Species in the ROW and Update of Databases
9.5 Planning for Invasives Control
9.6 Roadside Vegetation Control Methods and Resources
9.7 Management of Visual Quality of the Roadside
9.8 Staffing, Training, & Partnerships
Lists: Examples | Tables | Figures
Website Problems Report content errors and/or website problems
PDF Document Download Adobe Acrobat Reader