UC Delivers

Making avocado crops profitable in Ventura and Santa Barbara counties

The Issue

Since 1882, when Mexican avocado seedlings were planted in Ventura County, the industry has been slowly expanding. By 1942 there were 231 acres, 2,000 in 1954 and today there are 17,000 acres of avocados in Ventura and Santa Barbara counties. Initally there were few problems in the crop, other than searching for the ideal variety. For many years, avocados were one of the few crops in California that was unsprayed. Over time, a number of new pests have arrived. In the late 1940s, growers started seeing "avocado decline," a slow dying of the roots and canopies of the trees. ANR began the long-term study of what turned out to be a fungal disease that was renamed "avocado root rot." In the meantime, other problems began showing up in the $80 million avocado crop (2008) - diseases, pests and management issues, such as pruning, irrigating and fertilizing.

What Has ANR Done?

Working with growers, ANR campus- and county- based personnel began testing various methods for controlling root rot. This involved field studies to finally come up with a package of strategies to control the disease. Disease-control strategies include clonal rootstocks (disease-resistant), mounding, mulching, gypsum and some chemical treatments. Selection for more tolerant rootstocks continues, but now the rootstocks are also being selected for salt tolerance and resistance to other diseases. For the various waves of pests that have come through these orchards, we have devised biological control and management techniques, such as pruning and fertilizing to control these problems.

The Payoff

Avocado crop problems biologically controlled

In general, the avocado crop in Ventura and Santa Barbara counties is in good biological control, requiring few pesticides. The management practices developed by ANR have made avocados economically very attractive for coastal growers where the costs of labor, land and water are so high.

Contact

Supporting Unit: Ventura County

Ben Faber
805-645-1462
bafaber@ucdavis.edu
669 County Square Dr. Suite 100
Ventura 93003