Use the supplied Fertilizer Estimation Chart.
a. Use your previously recorded reference area NDVIref
value (taken in Step 1) and then locate the curve
closest to your value using the legend in the graph,
in this example
NDVI_ref = 0.8 A .
b. Use your previously recorded NDVIfp value (taken in
Step 2) and find this along the bottom axis of the
graph, in this example
NDVI = 0.6 B .
c. Go up from the field practice NDVIfp value at the
bottom of the chart to where it intersects with the
corresponding NDVI_ref curve C .
d. From the intersection point C , go directly to the left
to the point where it intersects the vertical (left
axis). This is the Normalized Rate, in this example
0.30 D .
e. Record this value.