Em4885 irrigation management practices to protect ground water

IP 2.02.07 - Drive a Tractor With No Tools in the Uncompacted Rows,
or Use a Short Shank in Compacted Rows, to Equalize the
Overall Infiltration Rates in Adjacent Furrows
Objective
Equalize the infiltration rates from furrow to furrow so as to improve the cross-row
distribution uniformity.
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CHAPTER 4
Description
Because tractor tires do not run in each furrow the infiltration rate of adjacent furrows may
not be equal. Thus, even if opportunity times were even there would be different amounts
of water infiltrated from furrow to furrow. One method to combat this entails trying to
equalize the infiltration rates by driving a tractor with no tools in the furrows that are
normally uncompacted.
The soil water content at the time of compaction will be critical. Too much water and
excessive compaction will occur. Too little water and there may not be any compacting
effect. Note, however, that the tractor tires will always act the same as a torpedo in
creating a firm, clod-free channel for water to run in.
Another method is to use a short shank in the rows where tractor tires run. It is critical to
not rough the furrow too much.
IP 2.02.08 - Use Laser-Controlled Land Grading to Take
Out High and Low Spots in a Field
Objective
Remove high and low spots in a field that could impede the smooth advance of water
down a furrow or border strip or create areas of excess soil moisture.
Description
One aspect of soil variability might be considered to be high and low spots in the field.
These can impede the smooth advance of water down a furrow or border strip and also
create areas of excess water infiltration where low spots exist. Laser-controlled land
leveling is a fast, accurate method to reduce the amount of high and low spots in a field.
Many growers will periodically “touch up” their fields to ensure uniform grades.
SCS National Practices 464 and 466 address land grading and smoothing.