Plant Health and Measuring the Red Edge
 First in Full Range PDA Spectrometer, Spectroradiometer and Spectrophotometer Systems
1 Canal Street  ◊  Unit B1
Lawrence, MA 01840  USA
Tel: 978 687-1833  ◊  Fax: 978 945-0372

Copyright © 2012 Spectral Evolution, Inc
Measuring plant health in the field can be done with a field portable
spectroradiometer from Spectral Evolution. The PSR+ is a full range
350-2500nm NIR spectrometer that is ideally suited for taking
vegetation measurements using our unique leaf clip and ILM-105
illumination source.

Many factors can affect plant health:
  • Lack of water
  • Over watering
  • Under fertilization
  • Pest infestation
  • Poor drainage
  • Soil compaction
  • Lack of nutrients

Using a PSR+ agricultural spectroradiometer and leaf clip, you can
scan individual plant leaves and measure health and stress by
looking at the red edge in the 680-760nm range of the leaf spectra.
The red edge is usually centered around 720nm. In healthy plants the
red edge shifts to the longer wavelengths - to the right on the
spectra. There is also a deeper absorption feature at 680nm
indicating there is more photosynthesis going on (more light being
absorbed). In a stressed plant, the red edge is further to the left -
toward the shorter wavelengths and there is less absorption and
more reflectance in a feature at 630nm.

The PSR+ combines high resolution with high sensitivity as well as
rugged construction for field use. All solid state arrays mean no
moving optical parts for greater reliability. Lightweight and with 2
slide-in lithium-ion batteries for a full day in the field, the PSR plus is
designed for single-user operation. The leaf clip has an external
trigger for ease-of-use and an external illumination source to keep
heat away from your samples.
 First in Full Range PDA Spectrometer, Spectroradiometer and Spectrophotometer Systems