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4. Precaution should be given if the access tube
is located at high water table areas, where the
access tubing must be sealed to prevent water
from outside.It is because the water in the access
tube can damage the capsule of neutron source
because scatters lots of neutron that cause very
high readings.

5. Actual counts are very useful because its reflects
the amount of moisture in soil. Furthermore, it
is must be related to contents of volumetric soil
moisture expressed in millimeter of water per cen-
timeter of soil using an appropriate calibration
data. This allowed the measured soil moisture
contents can be compared with the field capac-
ity of soil moisture contents. This will gives soil
moisture depletion and therefore actual depletion
can be compared with allowable depletion to de-
termine time to irrigate and how much volume of
water to supply.

6. Placement of Monitoring Sites: It is widely rec-
ommended that two sites for each 40 acres is
normal. However, more sites may be necessary
depending on soil variability and different in the
soil types. The maximum depth of access tubes
should be at least similar depth with the root zone.
However, measuring moisture contents at deeper
depths may be desirable for monitoring the water

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