Garden with Insight v1.0 Help: Soil patch next day functions: automatically irrigate if necessary
At this point in the soil next-day function, after water has entered the soil from rainfall and filtered
through the soil, after some water has evaporated out, and after the
water table has had its effect on the soil water, automatic irrigation occurs.
These conditions can prevent auto irrigation:
the auto irrigation option is
turned off
there was rainfall or snowmelt
today (any amount)
the soil was watered using a tool
since the last day of simulation (any amount)
the number of days that
occurred since the last auto irrigation is less than a parameter (which
prevents too-frequent watering)
the total amount of irrigation
water applied to this soil patch for the year exceeds a maximum parameter
If none of these conditions are met, automatic irrigation is triggered if the worst (smallest) water stress
factor for all plants in the soil patch is less than a parameter. Since the plants have not yet calculated their
actual transpiration or water stress, yesterday's water stress values are used to decide if auto irrigation is
needed. Note that auto irrigation never occurs when there are no plants in the soil patch.
The actual amount of water applied in auto irrigation is the smallest of:
the amount of water needed to
bring all the soil layers to field
capacity if the aspect "Ignore soil water content when irrigating" is "no"
the maximum amount of water
to apply in one irrigation application (a parameter) if the aspect "Ignore soil water content when
irrigating" is "yes"
the maximum amount of auto
irrigation allowed for the year (for a soil patch) minus what has already been applied this year
If the calculated amount of water is lower than the minimum amount of irrigation water allowed in any
application (a parameter), no application is made. The amount of auto irrigation water is added to the soil
patch during the percolation function.
calculation of soil evaporation, water
table depth, rainfall, snowmelt,
watering using a tool, water stress
factor, percolation
EPIC Auto Operations
Model contents
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