Time to Get Crackin’ on Mummies, Orchard Sanitation

The folks in the fancy suits on Wall Street call it ROI – short for return on investment.

Farm folks put it simpler terms: Is my time and money worth it now so I don’t lose money later?

Take the case of almond orchard sanitation and mummy nuts. Those are the stubborn nuts that refused to fall to the ground during shaking – even after a couple shakings during the harvest.

One long-time almond grower tells field scout Jenna Mayfield that he always sends crews out with hand poles after harvest to scour his orchard and manually knock off the mummies. 

“He swears up and down that he gets his money back the next season by doing orchard sanitation,” Jenna says. Getting rid of mummies lessens the likelihood of pest damage in next year’s crop. He also saves in pest treatment costs as well.

“There’s no reason for growers to wait until February,” Jenna says.

Knocking off mummies. (UC IPM photo)

Indeed, orchard sanitation remains important to control navel orangeworm (NOW) and protect against aflatoxin contamination. Growers should head into the orchard and check for mummies, where NOW can get their foothold.  As a rule, according to University of California Integrated Pest Management guidelines, trees should be cleaned to less than two mummies per tree.

UC IPM experts and UC Cooperative Extension farm advisers recommend sweeping or blowing the fallen mummies into center of the rows between trees. Then they should be destroyed by discing or mowing.

In the meantime, Jenna is preparing to inspect the estimated 4,000 almonds collected on the ground in orchards in Fresno, Merced and Madera counties during harvest and checking for signs of pest damage. Called crack-out, the task is a rite of fall for Jenna.

This season, Jenna collected four large boxes of almonds for crack-out. One by one, Jenna will crack each almond, peel off the shell and carefully examined the kernel and then jot down a few notes for growers. This tedious process of checking each of the 0 samples she collected helps guide pest management activities for the next year.

Jenna Mayfield will be cracking  lots of almonds.

Contrary to the disclaimers made by investment advisors, past performance can be a predictor of future results. So growers should check their monitoring records from this season and start preparing for dormant season activities.

In crack-out Jenna will look for signs of Peach twig borer (PTB) and navel orangeworm (NOW), which often like to infest the same nut. But NOW bores into the nut and PTB doesn’t. The NOW damage will cover over the PTB damage. NOW damage is represented by a webbing and powder-like remnants. She also will be keeping an eye out for signs of ant damage.

 After Jenna compiles her record, it will be up to growers to follow up on trouble spots and take appropriate steps to prevent pest problems in 2018. It’s hard to believe we’re almost into 2018.