Page 25 - 2025 GM spring

A New Tool for Precision
Irrigation on Golf Courses
Figure 2. a) The relationship between off-the-shelf PoLRa (turfRad) volumetric water content (VWC) and ground truth time
domain reflectometry (TDR) measurements from three golf course fairways during a survey at Champions Golf Club (Jackrabbit
Course) in Houston, Texas. b) A comparison of observed vs. estimated VWC using the ANCOVA regression approach.
In contrast, passive microwave
sensing, or microwave radiometry,
measures the natural microwave
emissions from the surface. This
passive approach is particularly
effective for assessing soil moisture
content, as it directly responds to the
water present in the soil.
MICROWAVE RADIOMETRY IN
GOLF COURSE MANAGEMENT
Microwave radiometry is emerging
as a promising technology for soil
moisture measurement, with
significant potential for large-scale
applications in golf course
management. An example of this
technology is the Portable L-Band
Radiometer (PoLRa), commercially
known as turfRad (TerraRad Tech
AG, Zurich, Switzerland). Although
PoLRa represents a new tool for golf
course Superintendents, the
principles of microwave radiometry
could transform how soil moisture is
monitored and how high-resolution
soil moisture maps are created.
Microwave radiometry detects
natural microwave emissions from
the surface, allowing for a soil
moisture measurement up to 4
inches below the surface. This non-
invasive method enables rapid data
collection over large areas, making it
ideal for managing extensive golf
course fairways, where traditional
soil moisture-sensing methods are
often labour-intensive or limited. The
radiometer sensor can be mounted
on a mower or strapped to the bed of
a utility vehicle, measuring soil
moisture about 14 times per second
while traveling up to 10 mph. Sensors
can also be arranged in an array for
broader coverage.
Although microwave radiometry
is still relatively new and has not
undergone extensive testing in golf
course management, it has already
been implemented at several golf
courses in the United States.
Technologies like PoLRa show
promise but are still in the early
stages of exploration. For precision
irrigation, any geospatial sensor
technology, including PoLRa, must
be rigorously evaluated by assessing
soil moisture measurement accuracy
and improving soil moisture mapping.
The preliminary research dis-
cussed in the next section focuses on
the first step: enhancing measurement
accuracy through calibration
GreenMaster • CGSA •
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