Even King Tut Would Just Say Nuts to These Mummies

This time of year, Jenna Mayfield sees tens of thousands of almonds carpeting orchard floors across the San Joaquin Valley.

Amid the drying almonds are mummy nuts.

Among the sea of green leaves and hulls and brown nuts drying on the ground are a sprinkling of black mummy nuts. Jenna bristles at this sight.

“It’s one of the things that drives me crazy,” Jenna says about the presence of mummies. “It’s frustrating.”

Like a broken record, Jenna along with UC IPM and extension advisors have stressed year after year the importance of ridding almond orchards of mummy nuts. This zero tolerance stance makes a lot of economic and environmental sense. 

Discolored kernels.

Research from the Almond Board of California and UC shows that leaving mummy nuts on the trees during the winter will boost the population of overwintering navel orangeworm (NOW) and ultimately increase the number of rejected nuts at the processor due to insect damage at harvest time. NOW damage also decreases overall yield. The almond industry sets a high bar for growers – reducing NOW damage to 2 percent. 

Almond experts point out that not every mummy nut has NOW damage. Some kernels remain intact for the second season but can be moldy, rancid or discolored. These, too, are rejects and impact the grower’s quality grade.

Get rid of those mummy nuts.

Jenna says some growers won’t bother with winter sanitation to save money. They don’t want to pay for workers to go from tree to tree knocking off the mummies.In the long run, that frugal practice can backfire. Growers either wind up spending more money to treat for NOW or losing more bucks because of the rejects and lower grade.

Moreover, knocking off the mummies is a good non-chemical solution to battle NOW infestation and nut damage. “Get rid of the mummies this winter,” Jenna says flatly.

Meanwhile, field scout Carlos Silva says cotton bolls have opened up in every field across the Valley. Aphids are still lingering and now whiteflies are starting to show up, too. Growers need to keep close tabs on these pests to avoid sticky cotton.

Carlos expects defoliation to start within the next couple weeks. That means harvest is just around the corner as we head down the back stretch of summer.

Alfalfa also is starting to wind down. Despite the severe drought, many growers had enough water to stretch the growing season into a fairly normal year. While aphids remain in the fields, their numbers aren’t high enough to warrant treatment.

Field Day Alert: Here’s a reminder thatthe Almond Post Harvest Management Field Day is set for 10 a.m. to 12:30 p.m. on Thursday at the corner of Mercy Springs Road and Cotton Gin Road in Los Banos. Pomologist David Doll of UCCE Merced County will talk about fall and dormant cultural practices to reduce disease and maximize next season’s tree productivity. UCCE IPM Advisor Dr. Jhalendra Rijal will discuss seasonal considerations for pest monitoring in almonds and Ganesh Vishwanath of SeaNutri will cover the use of seaweed-based products in farming. Two continuingeducation credits areavailable as well as CCA credits. For more information, contact Marcia Gibbs of the San Joaquin Sustainable Farming Project at (530) 370-5325.