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Soil Nutrients

Soil Nutrients

This page describes a method of identifying the proper quantities of soil amendments and fertilizer to add to a project site to help ensure long-term sustainable erosion control.

Developing a "Nutrient Perscription"

All sites have a minimum threshold level of nutrients that must be met for vegetation to establish and become self-sustaining. These nutrient levels can be restored by treating the project site with a variety of treatments, including topsoil, mulche, compost, as well as organic or commercial fertilizer. The process for developing a nutrient perscription typically follows the following event sequence:

  • Test Total Nitrogen Level - for reference and project site soils.
  • Identify Nitrogen deficiency in project site soils.
  • Determine nitrogen content and release rates of proposed amendments - Compost, Organic Fertilizer, and Commercial Fertilizer.
  • Calculate application rates of compost and organic fertilizer required to meet minimum threshold requirements.
  • Fill-out amendment application rates in project specifications.

Identifying Threshold Nutrient Levels

Identifying the threshold nutrient level (typically Nitrogen only) for a project site is a somewhat complicated, messy process. This process is well documented in the FHWA publication linked directly below, and it is suggested that designers follow this guidance to ensure sustainable vegetative cover that conserves water quality.

  • David Steinfield, Scott Riley, Kim Wilkinson, Thomas D. Landis, Lee Riley, et al. 2007. "Roadside Revegetation, An Integrated Approach to Establishing Native Plants" Accessed 2009-07-16

Calculating Nutrient Application Rates

Calculating nutrient application rates (typically Nitrogen only) for a project site is covered well in the publications linked directly below. Follow this guidance to ensure sustainable vegetative cover that conserves water quality.

  • David Steinfield, Scott Riley, Kim Wilkinson, Thomas D. Landis, Lee Riley, et al. 2007. Federal Highway Administration, US Department of Transportation, "Roadside Revegetation, An Integrated Approach to Establishing Native Plants"
  • Michael Hogan, 2009. "Sediment Source Control Handbook, An Adaptive Approach to Restoration of Disturbed Areas"

Prepare Project Specifications

Amendments can be added to a project site by using any one or combination of the erosion control treatment specifications listed below: