MARCH | APRIL 2015
Almond Facts
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applications can be made by applying a fixed proportion of ETc. In this method, the amount of water available for the
season should be calculated as a percentage of full ETc. This percentage should be applied to spread the deficit evenly
across the season.
In other words, if it is determined that enough water is available to supply only 55 percent of ETc for the whole season,
then each irrigation would match 55 percent of the determined ETc for that irrigation period. Current season and future
yield loss should be expected when using this strategy, but research has shown this to be the most effective strategy in
minimizing losses when available irrigation water is substantially reduced.
There are many other orchard practices that should be considered when managing drought. They include:
Removal Of Old
Blocks
Orchards will take two years of full
irrigation to bring back to near-normal
production. If water is short for the
entire orchard operation, it could be
diverted from older blocks in order to
save or reduce the recovery time of
younger orchard blocks.
Not Thinning Of Crop
Load
Research in peaches suggests that crop
removal has little, if any, impact on
water use and is not recommended. In
some cases, crop removal may increase
vegetative growth, which may increase
total water use.
Severe Pruning Is Not
Recommended
Stumping or "dehorning" of trees will
increase vegetative growth, which may
increase water demand. Furthermore,
studies have shown that more wood is
removed from the pruning treatments
than what is killed by severe water
stress.
Managing Increasing
Soil Salinity
Reduction of water applications or
reliance on low quality groundwater
may increase soil salinity, negatively
impacting yields. Almond trees are
relatively sensitive to sodium, chloride,
and boron. Yields are impacted when
average root system salinity increases
above 1.5 dS/m, with research
indicating a 19 percent decrease in
potential yield with every 1.0 dS/m
