Northern Virginia Planting Guidelines

Planting is reflective of the overall roadway. Traffic requirements, safety, natural features, environmental circumstances, and maintenance should be considered in the development of each design.

Planting may achieve a special purpose or function along the road.

 

  • Help provide safe and multi-use roadsides.
  • Water quality preservation protection and improvement.
  • Wetland and sensitive area protection.
  • Habitat protection and connectivity.
  • Erosion and sedimentation control and stormwater management.
  • Planting for traffic indication - i.e., bridge approaches, entrance and exit areas, change in horizontal alignment.
  • Planting to promote a positive quality of life for the community and the user.
  • Planting to improve long range maintenance operations.
  • Planting to improve the aesthetics of the area, and mitigate any negative impacts of transportation projects.

 

 

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Safety conditions influence plant location

 

Sight Distance is the distance at a given speed required for perception, reaction and braking time. Objects that would obstruct the driver’s sight, such as tall shrubs, and groundcovers, trees, light poles etc. may not be placed inside the sight triangle. Sight distance must be considered for signs, and for vehicles at intersections, signalized intersections, and entrance ramps, exit ramps and crossovers. It is also considered for vehicles moving through horizontal curves. Sight distance is always measured as a
straight line from the driver’s eye of the approaching vehicle to the fixed object, sign or to the driver’s eye of the stopped vehicle.

The link below will take you to the VDOT Road Design Manual, Appendix C. On Page C28 are table that give you the minimum sight distance based on the travel speed the road is designed to accommodate, generally five to ten miles per hour over the posted speed limit.
Road Design Manual Sight Distance

The link below will take you to the Florida Department of Transportation Sight Distance Diagrams. These diagrams illustrate the sight distance lines for various types of roads (please ignore the references to palm trees). This web site will have sight distance diagrams for Virginia soon.
Florida Sight Distance Diagrams

The Clear zone is a traversable recovery area for errant vehicles provided beyond the edge of the traveled way (edge of mainline pavement). The clear zone must be kept clear of fixed obstacles and must be considered for the entire length of the project.

The clear zone’s width is determined by design speed, traffic volume and embankment slope.

The clear zone must be free of fixed obstacles such as unyielding sign and utility poles, structures and major trees. Major trees are trees with a mature caliper size of four inches or more. They are classified as a fixed object. This type of tree is not allowed in the clear zone. Trees and landscape materials less than four inches in caliper at maturity may be placed within the clear zone where sight lines permit. Caution should be taken when selecting plant materials for these areas. The designer must understand the mature sizes and habits of the plant materials.

The link below will take you to the VDOT Road Design Manual, Appendix A. Section A-2 contains tables that give you the minimum clear zone, based on the type and steepness of the roadside, and the travel speed the road is designed to accommodate, generally five to ten miles per hour over the posted speed limit.
Road Design Manual Clear Zone

The following is a link to the North Carolina Planting Guidelines Section for Clear Zone. The diagrams and information can help you determine the 'clear zone' for the roadside plantings you propose. This web site will have clear zone diagrams for Virginia's roadways soon.
North Carolina DOT Clear Zone Planting Guidelines

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Roadside maintenance should be considered in the development of planting projects

Planting pits for shrubs behind guardrails should be located a minimum of one-half the anticipated spread (diameter) of the plant at maturity.

Plants in masses should be mulched completely between the planting pits.

Consideration should be given to plant hard to mow areas with masses of vines or shrubs
Mulch should extend to the front face of the guardrail or the edge of the shoulder.

Cultural characteristics, especially salt tolerance, should be considered.

A minimum of one mowing swath (6 feet) behind ditches should remain free of tree and shurbs.

Ditches should remain free of plant materials and mulch.

Other factors such as run off to and drainage of restricted areas, air pollution, and reflective heat of the pavement should be considered in selection of the plant material.

When masses of plants are desired, the pits should be spaced closely to allow rapid lapping of the branches.

The location of overhead and underground utilities should be considered in the selection of plant material.

Mowing operations (type of equipment, turning radius, etc.,) should be taken into consideration in the design.

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Process for Planting in VDOT Right-of-Way

Individuals, agencies or community groups who are interested in planting shrubs, flowers, or other plants in medians or other locations in the VDOT right-of-way may submit the following to the Virginia Department of Transportation Permits Section for consideration.

1. Complete and submit three copies of the Virginia Department of Transportation’s Land Use Permit Application.

2. Include three detailed drawings (one for each copy of the Land Use Permit Application) of the area to be planted. For example, if shrubs are to be planted in a median, the drawing should include the median, the streets adjacent to the median, sidewalks, stop signs, and anything else adjacent to the median. List the names and quantities of the shrubs to be planted.


3. Attach three copies (one for each copy of the Land Use Permit Application) of a Letter of Perpetual Maintenance signed by the individual or community group applying for a permit to plant in the VDOT Right-of-Way. The letter should state that the applicant(s) will be responsible for the perpetual maintenance of the items to be planted in the VDOT Right-of-Way. Upon approval of the Land Use Permit Application, which would include replacement of any planting that dies, the location without having to obtain an additional permit for maintenance purposes.

4. The Land Use Permit Application, detailed drawings with the Letter of Perpetual Maintenance should submitted to:

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Fairfax Permits Section
Virginia Department of Transportation Permit Section
4975 Alliance Drive
Fairfax, Virginia, 22030
703-259-1773


Loudoun Permits Section
Virginia Department of Transportation Permit Section
41 Lawson Rd.
Leesburg, Virginia 22075
703-737-2026

Prince William Permits Section
Virginia Department of Transportation Permit Section
10228 Residency Rd.
Manassas, VA 20110
703-366-2004

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Plant Selector

 

The Minnesota Department of Transportation has a Plant Selector  Please keep in mind that Minnesota is a lot colder than Northern Virginia. Northern Virginia is in Climate Zone 6 and Zone 7.

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How do I get more information?

 

Click here for a PDF of VDOT's Northern Virginia Planting Guidelines. (Coming Soon)

For additional information you may contact Ellen L. Vogel, District Landscape Architect at Ellen.Vogel@VDOT.Virginia.gov

This web site is possible through a grant from TreesVirginia (Virginia Urban Forest Council)

Page last modified: Jan. 24, 2014