August 31, 2014

Preventing Soil Salinity

The areas where almonds are grown in California are facing rising amounts of salt in the soil. And, the Imperial Valley and western San Joaquin Valley are at the greatest risk.1 According to the University of California, “Soil salinity has become a serious issue in California, with damage already occurring in some regions and some of the state’s most productive agricultural regions are in danger of becoming gradually less fertile.”2


1. There are dissolved salts in irrigation water.

2. As water evaporates it leaves the salt behind.

3. To leach salts beyond the root zone, more low-quality water must be applied.3

The above three factors result in a vicious circle of salinity. In his article Salt Burn and Stunted Growth—How Almonds Respond to Saline Conditions, David Doll, UCCE Farm Advisor, says high salt levels affect the trees in one of two ways: osmotic or toxic.4 Osmotic effects are the most common source of reduced growth and yield. This is because it makes it difficult for the roots to absorb water by hindering osmosis of water. Toxic effects are more noticeable because they cause leaf tip burn. The burn happens because salt enters the tree and travels to the leaves causing damage. Both osmotic and toxic effects damage yield.

Switching from well water to ditch water is one way to reduce the amount of salt you deposit via irrigation. This will help reduce the soil salinity. Another solution is to use fertilizers that have a very low salt analysis. Potassium sources containing chloride (MOP) should be avoided because of their high salt count. Taking the above precautions, using higher-quality water and low-chloride fertilizers, are just a few ways to protect your orchard from additional salt buildup.

For more information about low-chloride potassium sources, call Great Salt Lake Minerals at 1-855-308-3334.

1,3John Letey, UC Riverside, Soil salinity poses challenges for sustainable agriculture and wildlife, California Agriculture 54(2):43-48. DOI: 10.3733/ca.v054n02p43. March-April 2000.

2University of California Agricultural Issues Center, Soil Salinization, AIC White Papers on California Agricultural Issues November 2009. p 1

4 David Doll, UCCE Farm Advisor, Salt Burn and Stunted Growth—How Almonds Respond to Saline Conditions,, Monday, September 6, 2010