OMM December 2021 Archives - West Coast Nut


UC Models Can Assist with Pest Management Decisions

Pest and plant models, including UC-recommended degree day models, are available at the There are models for all the key tree nut pests including codling moth, navel orangeworm and peach twig borer. Growers and farm managers can use this collection of weather data and models to make management decisions on pest and disease control to either save money on production costs or justify the expense of an application. Growers may also find value in historical data on the site as they compare year-to-year pest and disease management decisions. Scope of the weather data available from the University of California...

Read More

Fungal Canker Diseases Spread During Dormancy

Fungal canker diseases and Phytopthora are two important conditions to watch for in almond orchards during the dormant season, which is when the peak sporulation of fungal pathogens occurs. Drew Wolter, Almond Board of California’s senior pest management specialist, said that fungal canker pathogens spread via spores released from fruiting structures. Rain or wind events spread spores to fresh tree wounds or breaks in tree bark. Following harvest, Wolter said, orchards should be scouted for shaker damage. If pruning is scheduled after harvest, fresh wounds should be treated prophylactically if rain is forecast in the next two weeks. Pruning wounds...

Read More

Vigilance for NOW Control in Walnuts

Dealing with navel orangeworm (NOW) is a numbers game, according to agronomist and PCA Robert Smith of Ultra Gro. “The fewer number of NOW overwintering in your walnut orchard is the outcome at the end,” said Smith, who grows walnuts in Tulare County. Postharvest is not the time to become complacent about orchard sanitation in walnuts, he stressed. “Sanitation should be a standard practice no matter what the grade sheet shows.” Orchard sanitation is easy to put out of your mind after harvest, Smith said. But if you had any NOW damage in your walnut crop, investing in sanitation will...

Read More

Combination of Control Tools are Best Bet for Gopher Invasions

Damage caused by invasions of pocket gophers in tree nut orchards can cause losses in the 5% to 6% range annually. Roger Baldwin, UCCE specialist, said in a UCANR webinar that it takes an integrated approach to achieve control of this vertebrate pest. Pocket gophers are burrowing animals that are rarely seen, but can inflict damage to tree roots, girdle tree trunks, cause water channeling and erosion and cause hazards to orchard equipment. Combinations of control methods can include baits, trapping and even biocontrol with predators. “There are variables, but you have to match the tools,” Baldwin said. There are...

Read More