Crop Spec, A Collaborative Partnership A real time integrated plant nutrient monitoring and application system for Agricultural equipment

Yara Electronic Products ,1995 - Present

CropSpecTM – specifications Environment IP 67 compliant Laser safety Class 1 or Class 1M Physical Dimensions 200 mm x 80 mm x 80 mm Mounting height 2 - 4 meters Viewing angle 45°- 55° Temperature 0 - 60°Celsius Operational wavebands 735nm and 808 nm +/- 3nm Supply voltage 10-32 VDC Supply current 1 A

Sensor Footprint – Oblique View

Decrease due to increased Impact of different N supply on the reflectance spectra of winter wheat Reflectance 0,6 N Supply Increase due to increased biomass 200 kg/ha 0,5 120 kg/ha 0,4 60 kg/ha 0,3 N response trail, 1994 0,2 Decrease due to increased chlorophyll content 0,1 IR 450 500 550 600 650 700 750 800 850 Wavelength, nm IR N status of crops can be measured by analysing reflectance spectral data => non-destructive, non-contacting

Waveband to Chlorophyll relationship The basis for getting meaningful crop information accurate measurements in various crops and over a wide range of crop densities based on know-how and extensive field trial work by Yara 730-740 nm & 760-810 nm Source: Reusch, 2005

Crop Spec System Diagram for X20 RS232 CANBUS Topcon X20 Implement with Liquid or Granular Application Supports all X20 application controllers

CropSpec Parameter Calculation Define: R = Simple ratio of NIR reflectance (808nm) to RedEdge (735nm) R = NIR/ RedEdge S1 = 100 * (R – 1) Compare NDVI = (R - 1) / (R + 1) The CropSpec parameter is defined: S1CAL = 47 * S1 / S1REF S1REF is the S1 measured with the reference matching filter. The 47 factor is used for matching with YARA.

X20 CropSpec User Interface – Maplink CropSpec (S1CAL) Histogram

CropSpec OTG Application Models Negative slope factor also available

OTG Two Point Cal – Strip method Drive Strip and Apply at Normal Rate Select min and max CropSpec from cutoff line Associate two rates => slope factor Select two point or target rate mode