Avocado is one of the most salinity sensitive horticultural crops, but is commonly grown in areas having saline irrigation water (an EC greater than 0.75 dS/m and chloride >100 ppm). Resulting problems associated with high soil salinity and chloride toxicity include reductions in fruit yield and tree size, lowered leaf chlorophyll content, decreased photosynthesis, poor root growth, and leaf scorching (Mickelbart et al., 2007). During recent years, salinity problems with avocado have become increasingly common as the cost for irrigation water has gone up and the availability of low salinity water for agriculture has diminished. This has resulted in requests for information on how water quality affects avocado yields so that growers can better manage salinity problems and make decisions on use of different water sources and root stocks.