Time to Split Coming Early for Almonds in the Valley, State

Early hull split. Farmers and almond experts anticipated it because of California’s drought and tight water supplies.

Jenna Horine spotted this splitting almond hull.

Well, it has arrived to the northern San Joaquin Valley. Field scout Jenna Horine confirms what had been a smattering of reports of an earlier than normal almond hull split occurring in orchards around the state.

 

Jenna spotted hulls splitting in an orchard along the Interstate 5 corridor in Los Banos in Merced County. That grower started hull split sprays over the weekend.

Hull split stages - initial separation

Hull starts to open up.

Initial drying of the almond.

Completely dry. (UC IPM photos)

In the past couple of weeks, almond expert and Merced County UC Cooperative Extension advisor David Doll had been receiving a few reports about early hull split from various locations around the state. He notes water stressed orchards and those with tight water allocations are most likely to see the early splitting of the green hulls. Usually, we see hull split in early to mid-July.

As a result, many farmers are anticipating an early harvest. Jenna, for example, points out one grower is getting a head start by preparing his orchard floors for tree shaking to knock off the nuts. 

Hull split is an important time for pest management. Growers treating for navel orangeworm need to time their summer applications to the start of hull split and egg laying. Peach twig borer and hull rot fungi also are threats at this time.

Here’s what UC IPM says: “The longer the nuts remain on the tree after hull split, the longer the interval that they are exposed to these invaders. Therefore, harvest your almond crop as early as possible to reduce the time it will be exposed to these pests and to avoid complications caused by early rains. If the threat of navel orangeworm is severe, the orchard can be harvested twice; once to remove the early ripening nuts and the second time to remove the later ripening ones.”

There is one catch: Not all the nuts ripen at the same time. Ripening will start on the upper and outermost sections of a tree. Experts recommend using pole pruners to cut branches from the top southwest section of a half dozen trees to see if hull split has started. Other UC IPM tips:  O

•  Continue monitoring trees until 95 to100 percent of the fruit at eye level are visibly split.
• Shake a few trees to determine if nut removal is satisfactory. If not, try again in a few days.
• Harvest blocks with poorest sanitation first. 

In the fields meanwhile, field scout Carlos Silva says alfalfa is on the verge of its third harvest of the season. Plants are approaching 24 inches in height, making them ready for harvest. Worms and lygus are on the uptick because of the recent heat wave, but they aren’t worrisome because of the upcoming cutting.

Carlos has reminded growers this is an important time to leave strips of uncut alfalfa if their crop is near a cotton field. This practice will maintain a habitat for the lygus and keep them from invading the cotton.

This strip cutting practice is important to protect cotton plans, which are developing nicely. Most plants are reaching 10 mainstem nodes with three to four fruiting branches. Right now, Carlos says lygus counts are low, but he anticipates finding more this week during his sweeps as alfalfa growers start cutting their crop.