TOFG-all

Reading & Interpreting Soil Test Reports

Unit 1.11 | Part 1 – 449

Demonstration 2: Nitrogen Budgeting

for the instructor

OVERVIEW

This demonstration offers an

example of how a simple nitrogen

budget can be calculated for an

organic farm or garden. Using the

nitrogen budgeting worksheets

and the Demonstration Outline

below, discuss and demonstrate the

process of calculating an estimated

nitrogen budget for a farm, factoring

estimated nitrogen release (ENR)

from compost, cover crops, and

existing soil organic matter. For

this exercise, Appendix 2 (Nitrogen

Budgeting Exercise) includes an

example of the steps involved in

calculating a basic nitrogen budget.

PREPARATION AND MATERIALS

• Appendix 2, Example of a Nitrogen Budget


• Appendix 6, Approximate Pounds/Acre of Nutrients
  Removed by Common Crops


• Sample soil test report

PREPARATION TIME

0.5 hour

DEMONSTRATION TIME

1 hour

DEMONSTRATION OUTLINE

A. Discuss rationale and goals of nitrogen budgeting

1. Meeting but not exceeding crop nitrogen requirements
   of crops

B. Discuss factors to consider in N-budgeting for organic

farming and gardening systems

1. Crop removal estimates and nutrient contributions of
   inputs (cover crops, compost, and ENR from SOM)

C. Demonstrate how to use the crop removal estimates

in Appendix 6 to provide an approximation of the

amount of plant nutrients that are removed from the

soil in a year by a specific crop or crops

1. This figure is placed on Line 1 of the Nitrogen Budgeting
   Worksheet (Appendix 3)

D. Discuss nitrogen contributions from three major

sources in organic farming systems: ENR from SOM,

compost, and cover crops

1. Demonstrate how to transcribe the estimated nitrogen
   release (ENR) figures from the soil test to the Nitrogen
   Budgeting Worksheet for calculating the nitrogen
   contribution of ENR (see Line 2 of the Nitrogen
   Budgeting Worksheet)
   a) Discuss the use of estimated nitrogen release in an
   annual and perennial cropping system
   b) Demonstrate calculations

Instructor’s Demonstration 2 Outline