University of California
A Mobile Light Sensing Unit
Outfitting the Mule
Using a handheld lightbar in measuring PAR, is a relatively slow and labor intensive method. For this reason, much of the lightbar data that was used to develop the relationship between PAR and yield was based on sampling a relatively small number of trees.
Fig. 1. Mobile unit to mefasure canopy light interception
We have recently outfitted a Kawasaki Mule with a light bar that is able to measure light across an entire orchard row. The data can be stored on a datalogger at intervals of less than 1 foot down the row, giving us a much better spatial resolution in much less time than was possible in the past.
Using the Mule's mounted lightbar setup, light interception and corresponding yield will be measured almond orchards throughout the almond growing area of California. The goal of this aspect of the work is to help establish the upper limit to the light interception/yield relationship for almond.
Ongoing work also involves retrofitting the Mule with sensors designed to develop the ability to detect water stress in trees.