FHWA-WFL/TD-07-006 October 2007

Federal Highway Administration

U.S. Department of Transportation

A Manager’s Guide to

Using Native Plants
Technical Report Documentation Page

1. Report No.

 FHWA-WFL/TD-07-006

2. Government Accession No. 3. Recipient’s Catalog No.

4. Title and Subtitle

A Manager’s Guide to Roadside Revegetation Using Native Plants

5. Report Date

 October 2007

6. Performing Organization Code

7. Author(s)

David E. Steinfeld, Scott A. Riley, Kim M. Wilkinson, Thomas D. Landis, 

Lee E. Riley

8. Performing Organization Report No.

9. Performing Organization Name and Address

 Umatilla National Forest

U.S. Forest Service

2517 S.W. Hailey Ave.

Pendleton, OR 97801

10. Work Unit No. (TRAIS)

11. Contract or Grant No.

12. Sponsoring Agency Name and Address

 Federal Highway Administration

 Western Federal Lands Highway Division

 610 East 5th St.

 Vancouver, WA 98661

13. Type of Report and Period Covered

Final Report 2007

14. Sponsoring Agency Code

 HFL-17

15. Supplementary Notes

 COTR: Amit Armstrong, Ph.D., P.E.

This project was funded under the FHWA Federal Lands Highway Technology Deployment Initiatives and 

Partnership Program (TDIPP) and Coordinated Technology Implementation Program (CTIP).

16. Abstract

This guide is intended to support managers in facilitating successful protection and/or establishment of 

native vegetation as an integral part of road design and construction. This report summarizes the concepts 

and approaches developed in Roadside Revegetation: An Integrated Approach to Establishing Native Plants, 

from a manager’s perspective. While the full report is designed for fi eld-level practitioners, it is this reference 

document that engineers and managers should use as a guide in project planning, design, and construction. 

This guide summarizes an integrated approach to eff ectively revegetating roadsides and other dis turbance 

areas associated with road construction, modifi cation, or obliteration. Management issues including 

scope, schedules, budgets, communication, and quality assurance are outlined as they relate to integrating 

revegetation practices. 

By incorporating an integrated approach to revegetation into project management, the end product, the 

fi nished road, will be a better product. The driving public, partners, and other communities aff ected by road 

projects—including the plants, animals, and other forms of life—will be better served by this approach. 

17. Key Words

REVEGETATION, NATIVE PLANTS, ROAD DESIGN, 

ROAD CONSTRUCTION

18. Distribution Statement

 No restriction. This document is available to the 

 public from the sponsoring agency at the website 

 http://www.wfl .fhwa.dot.gov/td/.

19. Security Classif. (of this report)

Unclassifi ed

20. Security Classif. (of this page)

Unclassifi ed

21. No. of Pages

24

22. Price

 $0.00

Form DOT F 1700.7 (8-72) Reproduction of completed page authorized
A Manager’s Guide to 

Roadside Revegetation 

Using Native Plants

Report Number: FHWA-WFL/TD-07-006

Technology Deployment Program

Western Federal Lands Highway Division

Federal Highway Administration

610 East 5th St.

Vancouver, WA 98661

Technology Deployment Report
SI* (MODERN METRIC) CONVERSION FACTORS

APPROXIMATE CONVERSIONS TO SI UNITS

Symbol When You Know Multiply By To Find Symbol 

LENGTH

in inches 25.4 millimeters mm 

ft feet 0.305 meters m 

yd yards 0.914 meters m 

mi miles 1.61 kilometers km

AREA

in2 square inches 645.2 square millimeters mm2 

ft2 square feet 0.093 square meters m2

yd2 square yard 0.836 square meters m2 

ac acres 0.405 hectares ha 

mi2 square miles 2.59 square kilometers km2

VOLUME

fl oz fl uid ounces 29.57 milliliters mL 

gal gallons 3.785 liters L 

ft3 cubic feet 0.028 cubic meters m3

yd3 cubic yards 0.765 cubic meters m3

NOTE: volumes greater than 1000 L shall be shown in m3

MASS

oz ounces 28.35 grams g 

lb pounds 0.454 kilograms kg 

T short tons (2000 lb) 0.907 megagrams (or “metric ton”) Mg (or “t”)

TEMPERATURE (exact degrees)

°F Fahrenheit 5 (F-32)/9 Celsius °C

or (F-32)/1.8

ILLUMINATION 

fc foot-candles 10.76 lux lx 

fl foot-Lamberts 3.426 candela/m2 cd/m2

FORCE and PRESSURE or STRESS 

lbf poundforce 4.45 newtons N 

lbf/in2 poundforce per square inch 6.89 kilopascals kPa

APPROXIMATE CONVERSIONS FROM SI UNITS

Symbol When You Know Multiply By To Find Symbol

LENGTH

mm millimeters 0.039 inches in 

m meters 3.28 feet ft 

m meters 1.09 yards yd 

km kilometers 0.621 miles mi 

AREA mm2

 square millimeters 0.0016 square inches in2

m2 square meters 10.764 square feet ft2

m2 square meters 1.195 square yards yd2

ha hectares 2.47 acres ac 

km2

 square kilometers 0.386 square miles mi2 

VOLUME

mL milliliters 0.034 fl uid ounces fl oz 

L liters 0.264 gallons gal 

m3 cubic meters 35.314 cubic feet ft3

m3 cubic meters 1.307 cubic yards yd3

MASS

g grams 0.035 ounces oz 

kg kilograms 2.202 pounds lb 

Mg (or “t”) megagrams (or “metric ton”) 1.103 short tons (2000 lb) T 

TEMPERATURE (exact degrees)

°C Celsius 1.8C+32 Fahrenheit °F

ILLUMINATION

lx lux 0.0929 foot-candles fc 

cd/m2 candela/m2 0.2919 foot-Lamberts fl 

FORCE and PRESSURE or STRESS

N newtons 0.225 poundforce lbf 

kPa kilopascals 0.145 poundforce per square inch lbf/in2

*SI is the symbol for the International System of Units. Appropriate rounding should be made to comply with Section 4 of ASTM E380. 

(Revised March 2003)
Table of Contents

FOREWORD 4

INTRODUCTION 5

BENEFITS OF NATIVE PLANTS 5

COLLABORATION, INTEGRATION, AND LONG-TERM GOALS 6

MANAGEMENT FOR INTEGRATING REVEGETATION: SCOPE, MILESTONES, BUDGETS, AND COMMUNICATION 9

SCOPE: WHAT AND WHY 9

STATEMENT OF WORK: WHO AND HOW 9

MILESTONES, COMMUNICATION, AND FUNDING 9

QUALITY ASSURANCE 14

PROCESS IMPROVEMENT 14

SUMMARY OF INTEGRATED APPROACH TO ROADSIDE REVEGETATION 15

ESSENTIAL STEPS 15

KEY CONCEPTS IN THE APPROACH 15

A WAY FORWARD 23
4

Establishing sustainable roadside vegetation is widely recognized as an essential and 

cost-eff ective practice to improve the safety, effi ciency, and eff ectiveness of roads and 

associated environment. In recent years, the Federal Highway Administration (FHWA) has 

taken a leadership role in moving beyond regulation-driven mitigation approaches and 

into proactive environmental stewardship to promote healthy ecosystems. Native plants 

are a foundation of ecological health and function in natural environments. Revegetating 

roadsides with native plants is a key practice for managing environmental impacts and 

improving conditions for healthy ecosystems. In addition, native plants along roadsides 

off er economic, safety, and aesthetic advantages. Well-planned, sustainable native 

vegetation supports trans portation goals for safety and effi ciency by stabilizing slopes, 

reinforcing infrastructure, and improving the road user’s experience by creating natural 

beauty and diversity along the roadside.

Reasons that many past attempts at native revegetation along roadsides have failed 

can be attributed either to a piecemeal approach or to lack of an integrated approach. 

Successful revegetation along roadsides using native plants requires forethought and 

planning. Revegetation planning must be an integral part of the process of designing 

and constructing roads.

This guide is intended to support managers in facilitating successful protection and/

or establishment of native vegetation as an integral part of road design and construction. 

This report summarizes the concepts and approaches developed in Roadside Revegetation: 

An Integrated Approach to Establishing Native Plants, from a manager’s perspective. While 

the full report is designed for fi eld-level practitioners, it is this reference document 

that engineers and managers should use as a guide in project planning, design, and 

construction. This guide summarizes an integrated approach to eff ectively revegetating 

roadsides and other dis turbance areas associated with road construction, modifi cation, or 

obliteration. Management issues including scope, schedules, budgets, communication, 

and quality assurance are outlined as they relate to integrating revegetation practices. 

By incorporating an integrated approach to revegetation into project management, 

the end product, the fi nished road, will be a better product. The driving public, partners, 

and other communities aff ected by road projects—including the plants, animals, and 

other forms of life—will be better served by this approach.

Figure 1 ~ Establishing desirable roadside vegetation is 

an essential and cost-eff ective practice to improve the 

safety, effi ciency, and eff ectiveness of roads and associated 

management. (Glacier National Park, photo by Tara Luna.)

FOREWORD
5

INTRODUCTION

Road users require that road modifi cations not 

only improve safety and mobility but also preserve, 

protect, and, where possible, promote healthy natural 

environments. In recent years the Federal Highway 

Administration (FHWA) has taken a leadership role 

in moving beyond regulation-driven mitigation 

approaches and into proactive environmental 

stewardship to promote healthy ecosystems. 

Native plants are a foundation of ecological health 

and function. Revegetating roadsides with native 

plants is a key practice for managing environmental 

impacts and improving conditions for healthy 

ecosystems. The ability to establish native plant 

communities on roadsides is central to determining 

whether the transportation corridor will be a healthy 

environment or a damaged one. However, past 

approaches to roadside revegetation often failed, 

despite policy initiatives, customer desires, good 

intentions, and widespread recognition of the many 

economic, aesthetic, and ecological benefi ts of native 

plants. 

Overcoming the obstacles to successful 

establishment of native plants requires more than just 

technical information. A systematic, comprehensive 

approach is needed. With environmental stewardship 

as one of FHWA’s “vital few” goals for road projects, 

native vegetation issues must be integrated with every 

phase of design and construction. Engineering and 

natural resource sciences must be brought together 

in a collaborative way. 

BENEFITS OF NATIVE PLANTS

Native plants along roadsides off er ecological, 

economic, safety, and aesthetic advantages. 

Ecologically, healthy native plant communities often 

are the best long-term de fense against invasive and 

noxious weeds. Economically, maintenance costs for 

managing problematic vegetation are reduced, as 

are the concerns that sometimes result when weeds 

from roadsides invade neighboring lands or when 

pollution from herbicides occurs. The ineff ectiveness 

of past roadside revegetation eff orts has resulted 

in problems such as erosion and sediment loading, 

thereby aff ecting soil and water quality. Visually, when 

road disturbance is not healed properly, the aesthetic 

experience of the road user is diminished. In terms of 

effi ciency and cost savings, poorly integrated natural 

processes can threaten the function and structural 

integrity of the road itself, leading to premature 

deterioration of the road’s infrastructure. 

The establishment of native plant communities 

supports transportation safety goals in a number 

of ways. One of the most important is by improving 

the function of roadside engineering. Appropriate 

Figure 2 ~ This debris slide took place two years after 

construction, when grasses were fully established. 

To preclude these kinds of problems, revegetation 

should have the establishment of long-term plant 

communities, not just quick cover, as a goal.

Figure 3 ~ Plant roots and stems increase slope stability 

by 1) reinforcing the surface horizon through a matrix 

of roots, 2) anchoring surface horizons to rock or 

subsoils, and 3) supporting the soil upslope.

INTRODUCTION
6

afterthought, results are often not as desired. The 

process must be collaborative, focused on long-term 

goals for ecological health, and fully integrated with 

larger design and construction issues. 

This guide outlines an approach to roadside 

revegetation that is: 

• Goal-oriented: Integrating long-term 

revegetation and ecological health objectives 

with larger transportation goals including 

safety, mobility, and cost eff ectiveness

• Collaborative: Incorporating the knowledge 

of engineering and natural sciences through 

collaborative processes and interagency 

cooperation

• Context-sensitive: Recognizing that each project 

has unique ecological characteristics and 

that source-identifi ed, locally adapted plant 

materials ensure functional, long-term, selfsustaining plant communities, not just quick 

cover

A comprehensive report, Roadside Revegetation: 

An Integrated Approach to Establishing Native Plants, 

brings theoretical and practical information to bear 

on the challenge of revegetating roadsides with 

native plants. Intended for fi eld-level practitioners 

and planners, the report is designed to help fi ll current 

information and technology gaps, share strategies and 

techniques, facilitate collaborative processes through 

interagency and interdisciplin ary coordination, and 

help readers through the process of successfully 

establishing native plant communities on roadsides. 

This publication, Roadside Revegetation Using Native 

Plants: A Summary Guide for Managers, outlines the key 

points from the approach of supervisors and planners. 

The approach off ered in these publications provides 

a goal-oriented, context-sensitive, collaborative 

approach to serve the needs of the customer for longterm ecological, economic, and aesthetic gains from 

establishing native plants on roadsides. In addition to 

necessary technical information, the process outlined 

shows how native vegetation concerns may be fully 

integrated into the larger processes of road design 

and construction.

Goal-Oriented

In past cases of failed revegetation eff orts, the 

goal was often too shortsighted. Revegetation was 

considered important to improve the appearance 

of the roadside disturbance, but eff orts emphasized 

seeding of exotic species because these were 

perceived as cheap, readily available, and quick to 

establish on disturbed sites. These exotics either 

spread to become problematic weeds, or failed to 

persist because they were not locally appropriate. 

vegetation can enhance visibility and support design 

features to help drivers recover if their vehicles leave 

the pavement. When native plant materials are 

incorporated into road design, they can improve longterm slope stability while softening visual experiences. 

For instance, hydroseeding with exotic grasses has 

been the conventional approach to stabilizing road 

cuts, but many grasses have shallow root systems and 

short lifespans. In contrast, hydroseeding with a mix 

of native forbs and grasses over a matrix of planted 

shrubs and small trees will increase slope stability and 

prevent slumps and debris fl ow onto the road. 

Well-planned, desirable vegetation supports transportation goals for safety and effi ciency by stabilizing 

slopes, reinforcing infrastructure, and improving the 

road user’s experience by creating natural beauty and 

diversity along the roadside. 

COLLABORATION, INTEGRATION, AND LONG-TERM

GOALS

To be successful, an integrated and collaborative 

approach to roadside revegetation is needed. When 

protection or re-establishment of native vegetation 

is approached in a piecemeal fashion or as an 

Figure 4 ~ This Guide for Managers summarizes the 

approach that is detailed in the larger report, Roadside 

Revegetation Using Native Plants: An Integrated 

Approach to Establishing Native Plants (pictured). The 

larger report is intended for fi eld-level practitioners and 

planners. 
7

Goals focused on long-term, functional communities 

of native plants, not just quick cover, are necessary. 

In addition, the setting and meeting of 

revegetation goals should be integrated with larger 

transportation goals of safety and mobility. To 

achieve this, it is essential to integrate native plant 

considerations into all stages of road development. 

Whenever disturbance to soils and vegetation are 

planned, a revegetation specialist should be involved. 

A revegetation specialist’s input serves to minimize 

the construction footprint and to plan to facilitate 

faster recovery of natural vegetation in the road 

corridor after disturbance. The revegetation approach 

is feasible technically and economically, and it is 

designed to produce long-term gains for native plants, 

ecological functions, soil and water protection, and 

other goals.

Collaborative

Collaborative approaches are a key to success. This 

guide illustrates timelines and processes for eff ective 

collaboration at any phase in the project. For example, 

the early stages of project development include key 

opportunities for integration. When disturbances 

to soils and vegetation are being discussed by the 

design engineers, the revegetation specialist can be 

involved in order to help determine what types of 

disturbances can be feasi bly revegetated with native 

plants. Often small revisions can result in greatly 

improved conditions for native plant establishment. If 

a planned disturbance will not allow for revegetation, 

alternatives to that type of disturbance can be 

considered. The work of the revegetation specialist in 

developing the revegetation plan, as well as eff orts to 

reduce the construction footprint and protect native 

vegetation on the project site, will become an integral 

part of the road construction plans. 

Coordination of schedules, milestones, and 

budgets is summarized in this guide. Collaboration is 

emphasized so the appropriate people are involved at 

key times to preclude problems and optimize results. 

This guide illustrates a generic process and shows how 

and when engineering and natural science specialists 

should be collaborating. The approach employed 

recognizes that fi nancial and personnel resources are 

limited. 

Context-Sensitive

Given the unique ecological factors at play in 

each project, the approach is not prescriptive but 

rather provides principles and a step-by-step process 

for practitioners to take into the fi eld to generate and 

implement their own locally appropriate, contextsensitive revegetation plan. Because the goal is plant 

communities that are functional in the long term, 

the approach is intended to facilitate the process of 

developing locally appropriate steps on a project-byproject basis. Top-down and ground-up information 

are integrated to meet the specifi c challenges at 

hand. For example, no ‘one-size-fi ts-all’ plant mix 

exists to apply under any circumstances and be 

successful. There are too many variables to make 

generic recommendations useful. Instead, the readers 

are guided through the conceptual aspects of every 

phase of a revegetation project. Steps are provided 

with examples so that personnel can identify unique 

site characteristics and how to best manage them. 

The process and tools needed are provided to arrive 

at appropriate solutions to revegetate any roadside 

project.

The Manager’s Role 

Establishing desirable vegetation is widely 

recognized as an essential and cost-eff ective step to 

improve the safety, effi ciency, and eff ectiveness of 

roads and associated management. By incorporating 

an integrated approach to revegetation in the overall 

project vision, the end product, the fi nished road, will 

be a better product. The driving public, partners, and 

other communities aff ected by road projects—the 

plants, animals, and other forms of life—will be better 

served by this approach. 

The manager’s role is essential in widening project 

scope to fully include environmental stewardship, in 

Figure 5 ~ Past approaches to revegetation often 

failed if the focus was on quick cover, not long-term 

goals. Integration of revegetation techniques into road 

planning and implementation increases chances of 

success.
8

ensuring context-sensitive objectives are set and met, 

and in supervising eff ective processes to get the job 

done within budget and on schedule. Coordinating 

teamwork to meet challenges in a collaborative and 

integrated manner includes bringing people from 

diff erent disciplines and organizations together and 

starting before any disturbance to soil or vegetation 

takes place. This guide is designed to support 

managers in facilitating successful protection and/or 

establishment of native vegetation as an integral part 

of road design and construction. 
9

The manager’s task is to ensure that the end 

product, the fi nished road, is completed effi ciently, 

eff ectively, and to high standards of excellence, 

including that “customer” expectations are met. The 

protection and establishment of healthy communities 

of native plants along roadsides has become part of 

the scope of road construction projects. Native plants 

help satisfy client demands, federal mandates, public 

concerns, and environmental stewardship goals, as 

well as providing improved cost savings and safety. 

To be eff ective, ecological thinking needs to 

be incorporated into all aspects of road design, 

construction, modifi cation, and maintenance. One 

way this goal is being addressed is to fully integrate 

issues of native plant revegetation (including 

protection of existing soils and vegetation) into the 

larger design and construction processes of road 

projects. Considering revegetation in isolation from, 

or as an appendix to, the larger road project is a trend 

of the past that often resulted in failure. Instead, 

revegetation planning is an integral part of road 

planning.

To ensure successful integration of revegetation 

issues with the overall road project, managers need 

to understand how the revegetation process works 

and how scheduling, funding, team communication, 

and other management issues relate to the process. 

To optimize results, the revegetation specialist should 

be involved as early as possible after a project is 

programmed, integrated at the appropriate times, 

and coordinating with the appropriate people. 

In general, the revegetation specialist should be 

involved in planning and construction processes 

whenever soil and vegetation disturbances are 

planned. Revegetation eff orts can be synchronized 

with schedules, milestones, and budgetary issues 

during road development and construction. Table 1 

shows some key points for managers to consider as 

they work to integrate revegetation with the project 

as a whole. 

SCOPE: WHAT AND WHY

With environmental stewardship as one of FHWA’s 

“vital few” goals, eff ective revegetation will be within 

the scope of any road construction, modifi cation, 

or obliteration process. It is important for managers 

to consider revegetation as an integral part of the 

project. 

In addition, the scope of revegetation eff orts 

should be recognized. Goals and objectives often 

consider both short-term environmental protection 

and long-term ecological health. Real economic, 

ecological, and aesthetic gains are realized when the 

objective is the long-term establishment of healthy 

communities of native plants. These plant communities 

are resilient and largely self-sustaining, with the 

capacity to stabilize soil, improve water quality, and 

resist invasions of noxious plants. Managers can 

help to ensure that the scope of revegetation eff orts 

includes true healing of the road scar, not just quick 

cover over the disturbance. 

STATEMENT OF WORK: WHO AND HOW

When assembling the project team, select a 

revegetation specialist and get her or him involved 

as early as possible in the planning process. A 

revegetation specialist should be a local resource 

person who knows the area and can generate contextappropriate solutions. A revegetation specialist 

may have a background in any number of natural 

sciences, including soil science, botany, ecology, or 

other fi elds. Good communication and organization 

skills, an ability to manage complex timelines and 

tasks, and a willingness to cooperate with other 

disciplines—engineering, hydrology, wildlife science, 

and so on—are important. A willingness and ability to 

learn engineering terminology and read construction 

plans is essential for eff ective communication. Involve 

the revegetation specialist before disturbances 

are planned. As the specialist begins work on the 

revegetation plan, consider the revegetation plan as 

an integral part of road construction plans—not as an 

appendix.

MILESTONES, COMMUNICATION, AND FUNDING

A key role of the project manager is to facilitate 

problem-solving in a collaborative and integrated 

manner. For revegetation and environmental 

stewardship, this means bringing people from 

diff erent disciplines and organizations together and 

encouraging engineering and natural scientists to 

cooperate before any disturbance to soil or vegetation 

takes place. Team members should be oriented to 

larger processes in order to create key relationships 

and navigate the decision process eff ectively. This 

input helps to optimize results, save money and time, 

and ensure that any disturbances planned can be 

eff ectively revegetated with native plants. 

In general, the revegetation specialist is usually 

involved just after the project is programmed, and 

MANAGEMENT FOR INTEGRATING REVEGETATION: SCOPE, MILESTONES, BUDGETS, AND COMMUNICATION
10

Table 1 ~ Managers should focus on the areas outlined in this table in order to successfully 

direct revegetation eff orts and integrate them with construction processes.

Management Focus Integrating Revegetation 

Project Scope: What and Why • Incorporate the establishment of healthy native plant 

communities on roadside as part of the project’s 

goals—native plants are important to meet customer 

expectations, fulfi ll policy mandates, and improve the 

fi nished road. 

• Ensure all members of the team are aware of native 

plants and ecological concerns as integral to project, 

not an afterthought. 

• Set goals for long-term ecological health and selfperpetuating native plant communities, not just quick 

cover.

Statement of Work: Who and How • Assemble team to include revegetation specialist 

before disturbances are planned. 

• Understand revegetation process and approach to 

support work. 

• Consider revegetation plan as an integral part of road 

construction plans, not an appendix.

Milestones: When • Understand timelines for revegetation processes 

so they may be successfully integrated with other 

processes.

• Ensure revegetation and construction activities will be 

complementary, not confl icting.

• Be aware that revegetation tasks often begin 1-3 years 

before construction and continue after construction is 

complete. Communication • Ensure key opportunities for collaboration are utilized. 

• Encourage cooperation between engineering and 

natural sciences—optimal results often come from 

collaboration.

• Involve revegetation specialist when disturbances to 

soil and vegetation are being planned or revised. 

• Allow special contract requirements to support 

context-sensitive revegetation needs.

Funding • Plan funding as needed for revegetation schedule. 

• Know that revegetation tasks begin 1-3 years before 

construction and continue after road construction is 

complete.

Quality Assurance • Ensure measurable goals are set and met for soil and 

vegetation. 

• Use context-sensitive goals, matched to unique site 

conditions.

• Ensure a reasonable approach is followed to reach 

goals. 

• Know that measurements of success may be 

qualitative and/or quantitative.

• Consider long-term ecological health and selfperpetuating native plant communities, not just quick 

cover. 

Process Improvement • Improve practice through sharing of lessons learned.
11

involvement continues through and following 

construction. It is important to note that the 

implementation phase of revegetation begins while 

the project development process is still underway. 

Waiting until construction begins is not feasible 

because locally-adapted native plant materials almost 

always have to be propagated in advance.

Essential points to coordinate revegetation eff orts 

with road planning and construction are illustrated in 

Figure 6, including budgetary and scheduling issues.

Planning and Programming

A project is considered “programmed” once it has 

been determined that the project will take place, and 

funding and a schedule for a specifi c delivery year have 

been set for that project. A revegetation specialist will 

usually not be involved in a project until after it is 

programmed, although at times one might be called 

in to assess the feasibility of various alternatives. 

Road Project Development

The road project development phase usually has 

three sub-phases. These involve developing, analyzing, 

and considering approaches and alternatives to the 

project until a strategy and specifi cations of how to 

best proceed are established in the fi nal plan. The 

process usually involves:

• Preliminary (road construction plans 30% 

complete)

• Intermediate (road construction plans 50%-70% 

complete)

• Final (road construction plans 70-100% 

complete, hand off to construction)

Preliminary

The preliminary phase is a crucial one for 

revegetation. This phase represents the best 

opportunity for input regarding issues associated 

with revegetation, including disturbances planned 

for existing soil and vegetation on the site. Signifi cant 

features of the preliminary revegetation plan should 

be incorporated during this road planning phase. By 

the time of environmental approvals, the vegetative 

concepts and the necessary commitments of 

resources and funds should be integrated with the 

plan, as revegetation will be an important aspect 

of environmental protection and mitigation. The 

appropriate level of detail for the revegetation plan 

during the preliminary phase depends on the project. 

For the revegetation specialist, some environmental 

guidelines may be predetermined by legislation that 

specifi es goals for the project regarding issues of soil 

stabilization, percent native vegetative cover, and 

protection of water quality. The revegetation specialist 

must be aware of these guidelines, and design 

them into the fi nal revegetation plan. Approvals are 

also key milestones for the revegetation specialist 

regarding availability of funds. This early release of 

funds is essential to carry out site assessments and 

revegetation planning work including, preliminary 

mapping and seed collections.

Intermediate

At the intermediate stage, the revegetation 

specialist should be far along in the development of 

the revegetation plan. Mitigating measures have been 

identifi ed for impacted areas and contracts for seed 

and seedling production have begun. The intermediate 

set of road plans will include specifi cations for how 

the project will be carried out. 

These specifi cations, particularly special contract 

requirements, are a key tool for successful revegetation. 

Special requirements address context-sensitive 

concerns for a particular project. Revegetation 

specialists should be encouraged and supported to 

adequately develop and describe special contract 

requirements to achieve the desired results in the fi eld. 

These might range from issues of soil or plant salvage 

to soil amendments, construction of topographical 

features, temporary soil stabilization measures, and 

the like. Because they will be part of the contract, not 

an afterthought, special contract requirements are a 

valuable tool for integration. Without them, the risk 

is that construction and revegetation activities might 

confl ict, instead of complementing each other. 

Final

The fi nal set of road plans will include the design 

elements of the revegetation plan, as well as the details 

for road construction. The work of the revegetation 

specialist in developing the revegetation plan, as well 

as input to reduce the construction footprint and 

protect native soils and vegetation on the project 

site, will be an integral part of the road construction 

plans, At this point, fi nalizing the revegetation plan 

will be necessary. It is also time to coordinate with 

contractors and agencies in order to time availability 

of plants with the proper time to establish plants in 

the fi eld. 
12

Environmental

Clearances & Approvals

Preliminary Road

Construction Plans

Project

Programmed

Project

Inception

Intermediate Road

Construction Plan

Final Road 

Construction Plan

Contract Award

Owner Agency

Acceptance

Maintenance Construction Road Project Development Programming Planning and

Periodic Meetings

with Construction

Final Monitoring

Report

Special Contract

Requirements

Contracts for

Plant Materials

Regular Construction 

Meetings

Implementation 

Tasks Begin 

Preliminary

Revegetation Plan

Revegetation

Planning Begins

Final Revegetation

Plan

Initiation Monitoring / Management Planning

Implementation

-1

0

1

2

3

4

5

6

7

8

-2

Revegetation

Aspect

Timeline Road

Project

Figure 6 ~ Coordinating revegetation with the larger processes of road construction is essential. While 

the timelines and agencies involved will vary, this fi gure illustrates some of the key opportunities for 

communication and integration.
13

Road Construction

Following project development, the project 

is often handed off to construction personnel. As 

shown in Figures 6 and 7, the revegetation specialist 

will have begun many of their implementation tasks 

while the project is still in the development phase. In 

addition, many of the revegetation tasks will continue 

during and after road construction. For these reasons, 

the construction engineer is an essential contact for 

the revegetation specialist. The specialist may attend 

a number of the weekly meetings that take place 

during road construction to help coordinate eff orts. 

Road Maintenance

After construction is complete, the work of the 

revegetation specialist will usually continue for an 

additional year or more until the revegetation is 

fully implemented. Usually, the submission of a fi nal 

monitoring report marks the end of the revegetation 

specialist’s involvement with the project. Coordinating 

road maintenance activities with the road-owning 

agency is necessary to ensure that maintenance 

activities do not undo portions of the revegetation. 

For example, if blanket herbicide use is conventional 

practice, alternatives will need to be selected. 

Summary of Revegetation Stages 

Figure 6 illustrates how processes for 

revegetation can be coordinated with the larger 

design and construction processes for road 

projects. This sidebar provides an outline of the 

revegetation side of the process. The report, 

Roadside Revegetation: An Integrated Approach 

to Establishing Native Plants, provides in-depth 

information on each aspect of the approach. 

Roadside Revegetation synthesizes an 

integrated approach that can be used for 

eff ective revegetation of roadsides and other disturbed areas associated with road construction, 

modifi cation, or obliteration. The four stages of 

the revegetation process are: initiation, planning, 

implementation, and monitoring/management. 

The fi rst stage, initiation, involves creating key 

relationships to navigate the decision process 

to initiate a proj ect. There are essential steps 

to coordinate revegetation eff orts with road 

planning and construction activities, including 

funding and scheduling issues. In addition, 

initiation involves creating bridges between 

nonengineers and engineers regarding 

terminology and technical concepts to improve 

communication. 

The second stage is planning—the process 

of defi ning project objec tives, assessing the 

site, overcoming limitations, strategiz ing 

revegetation procedures, and integrating the 

reveg etation activities with the road project. 

This stage culminates in the creation of a 

Revegetation Plan for the project. 

The third stage is implementation—executing 

the Revegetation Plan in the fi eld, including 

coordinating contracts and managing bud gets 

and schedules. Implementation involves carrying 

out site treat ments, mitigation measures, and 

revegetation tactics. This includes tasks to 

stabilize soils, overcome limiting factors, improve 

site conditions, and establish communities of 

native plants. 

Finally, the monitoring stage involves assessing 

the eff ectiveness of the revegetation project, 

correcting any short comings if goals were 

not yet met, and adding to future knowledge. 

Once vegetation has been established, longterm management dovetails with the practices 

outlined in Integrated Roadside Vegetation 

Management (IRVM) programs. 

Wild seed collection

Noxious Weed Treatment

Tasks

Year

Seed increase

Seed Storage

Seedling procurement

Topsoiling

Fertilizer procurement

Mycorrhizae procurement

Hydroseeding

Planting

Seedling mulching

Browsing control

-3 - -2 1 0 1 2 3

Implementation

Road Construction

Figure 7 ~ Example revegetation timeline for 

implementation. Note that revegetation tasks may 

begin three years prior to road construction, and 

continue several years afterwards. Coordinating 

timelines and budgets is essential.
14

QUALITY ASSURANCE

Another key role of the manager is to ensure that 

goals are set and met. This includes ensuring that a 

reasonable approach is being followed to both set 

and fulfi ll the goals. Because revegetation aspects 

will be dictated by the context and site conditions, 

no generic success criteria exist that apply to all 

revegetation projects. Instead, the revegetation 

specialist will develop revegetation objectives based 

on the site conditions. General goals of aesthetics, 

stability, function, and health can be provided in 

advance. Specifi c, measurable objectives, usually 

called Desired Future Conditions (DFCs), will be set 

by the revegetation specialist early in the planning 

phase. The manager can support this by ensuring that 

the revegetation specialist is following the approach 

outlined in the next section and detailed in the 

report, Roadside Revegetation: An Integrated Approach 

to Establishing Native Plants. Some measurements 

will be qualitative and some may be quantitative. 

Goals usually include some short-term needs, such 

as stabilizing soils, and long-term objectives for a 

healthy plant community. 

PROCESS IMPROVEMENT

Moving beyond piecemeal, mitigation-driven 

processes and into environmental stewardship is an 

ongoing challenge. In addition, restoration ecology 

is an evolving science and roadside revegetation is 

an evolving practice. Continual advances are being 

made on all these fronts. Lessons from revegetation 

practices, failures as well as successes, should be 

documented and shared. The revegetation specialist 

will document the technical aspects of their eff orts. 

Managers can help improve the fi eld of restoration 

by observing the overall process of road design and 

construction and by learning how to best facilitate 

and streamline to create improved results.

Management Should Ensure the 

Revegetation Specialist:

• Understands overall project objectives

• Keeps good records

• Understands cooperator processes, 

timelines, and milestones

• Is collaborating with the right people 

at the right time

• Is involved when disturbances to soil 

and vegetation are planned

Key Management Issues Regarding 

Roadside Revegetation

• Collaboration should begin before any 

disturbances to soil or vegetation take 

place and continue throughout the 

project. 

• Many revegetation implementation 

tasks (such as seed collection and plant 

propagation) need to begin 1-3 years 

before road construction begins. Funds 

need to be available accordingly.

• There are no “one-size-fi ts-all” criteria 

for revegetation success. Revegetation 

specialists develop context-appropriate 

objectives and plans based on ecological 

science and an understanding of site 

conditions. 

• Special contract requirements are a 

key tool for revegetation, essential for 

context-sensitive approaches. 

• Revegetation objectives dovetail with 

larger project objectives. 

• Often, optimal solutions are achieved 

through cooperation between 

engineering and natural science 

approaches. Communicating and 

sharing ideas and past experiences is 

essential to reaching a solution that 

benefi ts everyone. 
15

To supervise the successful establishment of native 

plants along roadsides, a general understanding 

of an eff ective approach to revegetation is useful 

to managers. A summary of the essential steps for 

revegetation planning is provided in this section. 

Table 2 provides an outline of the report, Roadside 

Revegetation: An Integrated Approach to Establishing 

Native Plants, so that managers can guide staff to 

consult this reference as necessary. Key concepts are 

highlighted to provide managers with an overview 

which they can use to support the setting and meeting 

of reasonable goals, the execution of an eff ective 

approach, and the coordination of collaborative 

processes. 

ESSENTIAL STEPS

To be successful, roadside revegetation needs to 

be approached in a systematic and comprehensive 

way. The goal is not simply to establish quick cover; the 

goal is to establish long-term, functional communities 

of native plants. Ecologically, roadsides and other 

road-related disturbances often represent drastically 

disturbed environments, where soil may be severely 

compacted and consist of a mixture of subsoil and 

parent material. Benefi cial microorganisms, nutrients, 

and organic matter necessary to sustain plant growth 

may be absent or severely depleted. Often, slopes 

can be steep or inaccessible, exposed to the erosive 

eff ects of wind and water. These environments 

represent a revegetation challenge of high intensity 

and magnitude. Soils, subsoils, and vegetation 

cannot be considered in isolation; they must be 

viewed collectively in order to successfully overcome 

limitations to establishing plants. Table 2 summarizes 

the essential steps for revegetation planning. 

Managers should note that some of the steps will 

be iterative, not linear. Key concepts associated with 

each step are summarized in the table. 

KEY CONCEPTS IN THE APPROACH

Initiation

Eff ective roadside revegetation requires not 

only technical skills, but also an ability to cultivate 

 What are Native Plants?

“Native plants,” as defi ned in this approach, 

are locally-adapted, genetically appropriate 

native plant materials (Withrow-Robinson and 

Johnson 2006). These plants are best suited 

evolutionarily to the local conditions, and 

generally require less maintenance and persist 

longer than non-local species. When properly 

established, they form plant communities 

with the potential to be self-sustaining and 

self-perpetuating over time, requiring little or 

no input from humans to continue and thrive. 

Recent policy mandates from many federal 

agencies that manage roads now require the 

use of native plant materials as the fi rst choice 

in revegetation eff orts. 

Figure 8 ~ The establishment of locally-adapted 

native plant communities is a cornerstone of 

ecological restoration.

SUMMARY OF INTEGRATED APPROACH TO ROADSIDE REVEGETATION
16

Table 2 ~ Overview of essential steps for roadside revegetation. Managers should note that some steps will be 

iterative. Key concepts associated with each step are summarized in the text. Links to the full report, Roadside 

Revegetation: An Integrated Approach to Establishing Native Plants, are provided so managers can guide staff to 

consult this reference as necessary.

Section Chapter Goal Tasks

Initiation 

Part One

Chapter 2 Understand cooperators 

and decision processes

Set up recordkeeping

Identify cooperators: Who is involved?

Defi ne cooperator processes, timelines, and milestones

Defi ne objectives: What is the project trying to accomplish?

Initiation 

Part Two

Chapter 3 Understand road plans and 

terminology

Read and interpret road construction plans

Understand key concepts and terminology

Planning 

Phase One

Chapter 4 Orient to the project Determine revegetation objectives

Defi ne revegetation units

Select reference sites

Defi ne the desired future conditions

Planning 

Phase Two

Chapter 5 Assess site Identify limiting factors

Consider mitigating measures for limiting factors

Assess site resources

Planning 

Phase Three

Chapter 6 Analyze vegetation Complete vegetation assessment

Create a comprehensive species list

Defi ne plant communities and successional processes

Determine which species and groups of species will be 

used on the project

Identify target plant requirements

Create menu of potential stocktypes and plant 

establishment methods

Planning 

Phase Four

Chapter 7 Integrate and strategize Finalize revegetation units and DFCs

Integrate survey information and develop potential 

revegetation strategies

Compare and select revegetation strategies

Assemble revegetation plan

Chapter 8 Example plan Example revegetation plan

Implementation Chapters 

9 and 10

Implement Review plans with construction engineer

Review revegetation treatment details and timelines

Develop contracts

Install treatments

Keep good records

Carry out quality control

Implement early maintenance and monitoring

Monitoring &

Management

Chapters 

11 and 12

Monitor, evaluate, correct, 

improve

Revisit project objectives and DFCs

Develop monitoring strategy and protocols

Record data and observations

Evaluate data and apply any corrective measures

Organize and fi le project results

Share lessons learned
17

Construction plans provide information necessary 

to understand the current project site conditions, as 

well as to predict the future condition of the project 

site following road construction. 

Planning 

Planning forms the foundation of future work. The 

process of planning is organized into four phases.

Planning Phase One

Phase One involves defi ning four essential 

aspects of the project: 1) the revegetation objectives; 

2) the management areas (revegetation units); 3) the 

natural models (reference sites); and 4) the specifi c 

goals for each revegetation unit (called desired future 

conditions, DFCs). Defi ning these steps requires 

a preliminary assessment of site characteristics, 

including vegetation, climate, and soil.

relationships and navigate the decision processes so 

that a project will run smoothly. Road construction, 

alteration, or decommissioning involves a variety 

of land management agencies, programs, and 

regulations. Revegetation specialists need to learn 

about agency procedures for the organizations 

involved with road projects. Timelines, budgetary 

issues, and interface opportunities are considered 

to enable the revegetation specialist to integrate 

revegetation eff orts with the overall process of road 

planning and construction. Attending meetings and 

coordinating with key contacts within agencies are 

important tasks in the early stages of the project. 

In the initiation phase, the revegetation specialist 

needs to become familiar with reading and interpreting 

road plans and understanding terminology. This 

ability enables the specialist to communicate 

eff ectively about engineering plans, contribute fully 

to minimizing the adverse environmental impacts, 

and ensure that revegetation is an integral part of the 

eff orts. 

The Process of Succession: Change Over 

Time

Native species play an important role in 

ecosystem development over time. If native 

species can colonize and become established 

on a disturbance, the processes of succession, 

including soil genesis and nutrient cycling, 

are initiated. Eff ective revegetation of highly 

disturbed roadsides aims to initiate or 

accelerate processes of natural succession 

following disturbances. In most cases, native 

plants are established on roadsides through 

seeding or planting, although sometimes 

passive revegetation (natural colonization) 

is possible where native seed banks are 

nearby and limiting factors are mitigated. The 

establishment of native plant communities 

in order to re-initiate natural processes of 

succession is a cornerstone of most ecological 

restoration eff orts. 

 Figure 9 ~ Successional processes and plant 

communities vary considerably based on site 

conditions. In this example, plant communities 

developed diff erently over a ten-year period on northfacing and south-facing slopes. 
18

Determine Revegetation Objectives

Revegetation objectives are linked to larger project 

objectives for safety, mobility, and environmental 

protection. Most revegetation projects state several 

objectives to address both short-term and longterm outcomes. For example, short-term, immediate 

revegetation objectives on most projects include 

erosion control and water quality protection through 

mulch and vegetative cover. Long-term revegetation 

objectives might include the exclusion of invasive 

weeds, visual enhancement, and establishment 

of healthy native plant communities through soil 

restoration. While short-term objectives might rely 

on quick-growing ground covers such as grasses and 

forbs, long-term objectives are often broadened to 

include such revegetation treatments as planting 

deep-rooted tree and shrub seedlings to stabilize 

roadsides, creating visual screens, and/or supporting 

sustained plant community development. As the 

project evolves, objectives are translated into specifi c, 

measurable goals (DFCs). After the installation is 

complete, DFCs and revegetation objectives will be 

utilized in monitoring, evaluating, and managing the 

project.

Defi ne Revegetation Units

Revegetation units are delineated on the project 

site. These are areas within the project site that are 

similar enough to be appropriate for similar strategies 

and treatments. Homogenous sites will have only a 

few units; sites with greater diversity (e.g., diff erent soil 

types, microclimates, vegetation types, management 

needs) will have more revegetation units. Each 

unit is distinct in terms of ecology, management 

requirements, or both. Goals will be set appropriate 

to the conditions in each unit. 

Select Reference Sites

Identifying and surveying reference sites or natural 

models for the desired recovery process is essential to 

setting attainable, site-appropriate goals regarding 

revegetation. Reference sites provide guidance about 

what species may be established and how their plant 

communities will change over time. Reference sites 

are natural or revegetated areas that serve as models 

for desirable recovery of native plant communities. 

One or more reference sites are identifi ed for each 

revegetation unit in the project.

Defi ne the Desired Future Conditions (DFCs)

DFCs are specifi c, measurable goals for each 

revegetation unit, usually defi ned in terms of the 

percentage of vegetative cover, ground cover, species 

composition, and so on. Once revegetation units and 

corresponding reference sites have been identifi ed, 

mapped, and described, an appropriate desired future 

condition (DFC) can be defi ned for each unit. The DFC 

takes the overall revegetation objectives defi ned 

earlier and translates them into measurable goals 

tailored to each revegetation unit. The DFC specifi es 

the desired or expected composition of vegetation 

at a defi ned point in time after the completion of the 

revegetation work. An example DFC would be, “two 

years after seeding, vegetative ground cover will be 

50%; of this cover, 75% will be composed of perennial 

native species.” Stating expectations in this manner 

will:

• Clarify how the site will appear after 

treatments;

• Narrow down the appropriate revegetation 

treatments;

• Defi ne measurable criteria, or success thresholds, 

that can be used to manage activities and 

monitor project development. 

Planning Phase Two

Phase Two defi nes site attributes and limiting 

factors. Factors critical for plant establishment, 

such as soil and climate, are assessed. Obstacles 

to revegetation, as well as available resources, are 

examined. A fi eld investigation of each revegetation 

unit describes the site in depth and reveals how site 

characteristics will either support or limit achieving 

the DFCs. Based on the determination of limiting 

factors, a menu of possible mitigating measures for 

assuring plant establishment (short-term) and plant 

Figure 10 ~ Context-sensitive revegetation planning 

includes mapping revegetation units on the project site 

to account for variations in soils, climate, management 

considerations, and other factors. Goals will be set 

appropriate to the site conditions in each unit.
19

community development (long-term) is developed. 

Any mitigating measure that will be applied, including 

soil and site treatments, should be prescribed to 

overcome specifi c limiting factors identifi ed on 

the site. Attempting to intervene on the site before 

identifying limiting factors is akin to a doctor writing a 

prescription without taking the time to diagnose the 

problems. 

Planning Phase Three

Phase Three matches plant species, genetic 

sources, stocktypes, and planting methods to the 

environmental conditions of the site. The vegetation 

is surveyed and analyzed. From a comprehensive list 

of species and plant communities present on the 

reference sites, the revegetation specialist determines 

which species are best adapted to the site and best 

suited to revegetation needs. Options for sources, 

stocktypes, and application methods are considered 

in order to achieve the desired results. 

Figure 11 ~ A comprehensive survey of potential 

limiting factors to establishing vegetation should be 

carried out. All mitigation strategies should be designed 

to overcome specifi c limiting factors.

Precipitation

Interception

In ltration

Road Drainage

Soil Texture

Rock Fragments

Soil Structure

Rooting Depth

Mycorrhizal Fungi

Wind

Aspect

Competing Vegetation

Soil Cover

Topsoil

Site Organic Matter

Nitrogen and Carbon

Nutrients

pH and Salts

Rainfall and Wind

Freeze – Thaw

Soil Cover

Surface Strength

In ltration

Slope Gradient

Surface Roughness

Slope Length

Permeability

Restrictive Layer

Water Input

Slope Length

Slope Gradient

Soil Strength

Weed Sources

Weed Growing Environment

Mammals

Insects

Disease

Road Maintenance

Recreational Use

Water

Input

 Critical 

Plant Factors Parameters

 Water 

Loss

Nutrient

Cycling

Surface

Stability

Slope

Stability

Weeds

Pests

Human

Interface

 Water Storage 

and 

Accessibility

1

2

3

4

5

6

7

8

9

Figure 12 ~ List of limiting factors and their 

parameters.
20

Planning Phase Four

Phase Four combines all elements into a 

comprehensive strategy for revegetation. The 

possible options for site mitigation and revegetation 

methods are compared and considered, and the most 

promising are selected. Choices will be based on site 

factors and plant needs, and on other considerations, 

such as costs and availability of materials and services. 

There are always several ways to meet the revegetation 

objectives, and diff erent options are considered in 

Phase Four. When preferred strategies have been 

selected, budgets and schedules are developed and 

recommendations are compiled and presented in the 

Revegetation Plan. 

Implementation

Implementation involves coordinating and 

cooperating with diff erent contractors and agency 

personnel before, during, and after construction of 

the road. Treatments for soils and site conditions, 

obtaining plant materials, and installing and caring 

for plants are part of the implementation process. The 

revegetation specialist needs to review plans with 

engineers, fi nalize treatment details and timelines, 

and develop the contracts necessary to successfully 

carry out the treatments. Keeping good records and 

carrying out quality assurance and early maintenance 

activities are essential aspects of the implementation 

phase. In all cases, coordinating the revegetation work 

with road construction or modifi cation processes is a 

major challenge and a key opportunity to improve 

conditions for native plants. 

As a resource, Implementation Guides in the 

Roadside Revegetation: An Integrated Approach to 

Establishing Native Plants report illustrate how to 

implement and/or contract for a particular treatment 

or mitigation measure. Guides are provided for: 1) 

working with soil/site treatments, 2) obtaining plant 

materials, 3) installing plant materials, and 4) caring 

for plants. 

Monitoring and Management

Monitoring is necessary to determine if goals 

defi ned at the outset of the project have been met. 

Scope, methods, and parameters for monitoring are 

determined on a project-by-project basis and must 

be developed so that suffi cient and meaningful 

information is obtained effi ciently and interpreted 

properly. Keeping written records throughout the 

process of roadside revegetation is essential in order 

to evaluate each project.

39.37 inches 1meter

RL Supercell

D16 Deepot

Short One Treepot

Tall One Treepot

2 Gallon Treepot

PVC Tallpot

Ball-and-Burlap

Figure 14 ~ Nursery stock is available in many container 

sizes and shapes. Revegetation specialists should 

consider advantages and drawbacks of diff erent 

options before ordering plants.

2. Type of Plant Material

5. Timing of Outplanting Window

6. Outplanting Tool or Technique

3. Genetic Considerations

4. Limiting Factors on 

 Outplanting Site

1. Objectives of Outplanting Project

Figure 13 ~ The target plant concept identifi es six 

requirements for establishing native plants.
21

1

Water

Input

Critical Plant 

Factors Parameters Mitigating Measures

2

Water 

Storage

and

Accessiblity

3

Water 

Withdrawal

4

Nutrient

Cycling

5

Surface

Stability

6

Slope

Stability

7

Weeds

8

Pests

9 

Human

Interface

Rainfall

Interception

Infiltration

Road Drainage

Soil Texture

Rock Fragments

Soil Structure

Rooting Depth

Mycorrhizae

Humidity

Wind

Aspect

Competing Vegetation

Soil Cover

Climate

Topsoil

Site Organic Matter

Nitrogen & Carbon

Nutrients

pH & Salts

Rainfall & Wind

Freeze-Thaw

Soil Cover

Surface Strength

Infiltration

Slope Gradient

Surface Roughness

Slope Length

Water Input

Hydraulic Conductivity

Restrictive Layer

Slope Length

Slope Gradient

Soil & Root Strength

Bare Soil

Weed Propagules

Native Propagules

Nitrogen

Mammals

Birds

Insects

Diseases

Road Maintenance

Recreation Use











































irrigate, deep sow, mulch, high density sowing

deep tillage, harrow, disk, mulch

compost, clay

deep tillage, compost, topsoil

deep tillage, compost

topsoil addition, mycorrhizal inoculum

mulch, surface roughness

mulch, deep sow

topsoil addition, manufactured topsoil

incorporated litter duff, mulch, logs

nitrogen-fixing species, topsoil, fertilizers, compost

topsoil, fertilizers, compost

mulch

mulch

mulch

mulch, tackifier

disk, harrow, compost

reduce slope length

prevent and control, quick native revegetation

sow non-palatable or non-desirable species

Figure 15 ~ Mitigation measures are matched to site conditions. The goal is to overcome 

limiting factors to long-term plant establishment and to initiate healthy ecological 

processes. This fi gure shows some mitigation measures considered to overcome a 

specifi c site’s limiting factors.
22

BUILDING ON A LEGACY

FHWA is a pioneer in addressing concerns 

about incorporating native plants in road 

projects. In 2000, FHWA published a landmark 

book edited by B.L. Harper-Lore and M. Wilson, 

Roadside Use of Native Plants, that brought the 

importance of roadside native plants to national 

attention. Since then, FHWA has been a leader in 

supporting information resources and research to 

establish and manage native plants. FHWA helped 

support the development of Integrated Roadside 

Vegetation Management (IRVM) programs to 

better manage roadside plants beyond repeated 

applications of herbicides. FHWA also helped 

support the National Academy of Sciences in 

producing the report Assessing and Managing the 

Ecological Impacts of Paved Roads.

Internally, FHWA also has invested in several 

initiatives to improve integration of ecological 

concerns with road planning. These programs 

include the Eco-Logical approach, context sensitive 

solutions, Exemplary Ecosystem Initiatives, the 

newly forming Green Highways Partnership, and 

other cutting-edge initiatives and policies.

Roadside Revegetation: An Integrated Approach 

to Establishing Native Plants builds on these 

visions by applying the concepts of integrated 

planning, ecological thinking, context sensitivity, 

and environmental stewardship to the challenge 

of establishing native plants on roadsides. 

Advances are being made in utilizing 

native revegetation in transportation projects, 

and progress is underway in the science and 

practice of restoration ecology and native 

plant propagation. For example, the Society for 

Ecological Restoration International recently 

published guidelines and principles applicable to 

restoring ecological function to degraded sites. 

Plant geneticists at a number of federal agencies 

came to a consensus about what truly defi nes a 

“native” plant and developed seed collection, 

transfer, and propagation guidelines to ensure 

that locally adapted materials are used with 

optimum results. In both the public and private 

sectors, seed and plant producers and installers 

have developed innovative methods to meet 

unique site conditions. Roadside Revegetation

brings these advances to bear on the unique 

challenges of roadside environments. 

Monitoring continues several years after 

implementation, providing a chance to assess 

eff ectiveness and correct any shortcomings. In the 

Planning stages, project objectives were developed 

to describe an overall vision for the project. The DFCs 

refi ned the objectives into specifi c, measurable goals 

for the project site. Monitoring is an opportunity to 

evaluate the eff ectiveness of the revegetation eff orts 

as they relate to objectives and goals. 

Monitoring is essential for adaptive management 

of the project. Adaptive management is a systematic 

approach to good management guided by a process 

of regularly assessing and learning from what works 

and does not work on a project. As a project develops, 

monitoring can be used to assess progress and plan 

any necessary corrections.

When statistical methods will be necessary, 

monitoring protocols are available, describing 

statistical sampling design, data collection techniques, 

and analysis methods for quantifi able parameters 

to determine success of roadside revegetation 

projects. Monitoring protocols cover the following 

measurements:

• Soil cover – to determine if treatments increased 

soil cover for erosion control.

• Species cover – to determine if treatments 

increased native grass and forb cover.

• Species presence – to determine if there was an 

increase in the number of seeded native grass 

and forb species.

• Plant density– to determine how many 

seedlings or cuttings became established after 

planting to assess whether stocking is adequate 

or the site needs replanting. Plant survival can 

also be determined from this protocol.

The

Project

Cycle

Initiation

Adapt

and

improve

Initiation

of

Future Projects

Monitoring/

Management

Implementation

Planning

Figure 16 ~ The revegetation project cycle.
23

• Plant attributes – to determine how fast planted 

shrubs and trees are growing.

Revegetating roadsides with native plant 

communities is a developing fi eld. Practitioners 

are encouraged to share lessons learned, including 

successes and failures, to improve the knowledge 

base for future work.

A WAY FORWARD

Balancing ecological health with safe and effi cient 

transportation is an enormous challenge. Revegetation 

success is a key factor in determining whether the 

over 12 million acres that make up the transportation 

corridor of the United States will be hospitable 

environments to plants and other forms of life—or a 

wasteland. It is hoped that continuing improvements 

in interagency cooperation, enlightened policies, 

better science and technology, and the dedication of 

managers and fi eld-based practitioners will continue 

to build a foundation for a more sustainable future. 

Figure 17 ~ Beginning revegetation with native 

species on scenic highway to Mt. Bachelor, Oregon.
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Technical Report published by

Technology Deployment Program

Western Federal Lands Highway Division

Federal Highway Administration

610 East 5th St.

Vancouver, WA 98661

For more information or additional copies 

contact:

Amit Armstrong, Ph. D., P.E. 

Phone: 360.619.7668

Fax: 360.619.7846

Amit.Armstrong@fhwa.dot.gov