Almond Trees Can Tolerate Drought – But It Comes with a Price

With Californians urged to use water wisely, many Valley residents are planting drought tolerant landscaping. Communities such as the City of Clovis in Fresno County even publish approved lists of drought tolerant plants.

Desert willow tree is good for drought-tolerant landscaping.

Desert willow, cuayamaca cypress and coast live oak are among the trees listed as very low water users. Perhaps, we should suggest adding the almond tree.

Yes, almond trees can tolerate drought conditions. In fact, these trees can survive on as little as 7.6 inches of water annually, according to a February 2015 University of California Agriculture and Natural Resources report called “Drought Management for California Almonds.”

Of course, there’s a huge difference between a desert willow and an almond tree. A water-stressed willow won’t hit a farmer’s pocketbook like a thirsty almond tree.

Alas, drought survival comes with a price.Less water reduces growth and yield. Ideally, almond trees need 54 to 58 inches of water for maximum production.

“If you’re cutting your third or fourth year of deficit irrigation, you’re going to see your crop not yielding as much as in the past,” says David Doll, a pomologist and noted almond expert with UC Cooperative Extension in Merced County.

In fact, reducing irrigation produces a double-whammy for growers: A smaller yield this season and the next year as well.

Almond trees are considered drought tolerance.

Doll says trees will adjust to and become stable if the water drop-off isn’t too steep. “What we’re seeing is if a tree is maintained at an irrigation rate of 70 to 90 percent of normal it will stabilize at that amount of water application.” Of course, that depends if a grower has enough water available to even maintain irrigation at a 70-90 percent level.

Dry times are causing other worries, Doll adds.

“What is becoming more of a concern in these times of drought is the accumulation of salt within the root zone. We can get an impact from salinity due to the increase in salt load, which makes the tree work harder. If you apply the same amount of water you may not see the same response from the tree.”

This means trees with a high amount of root zone salinity are thirstier and giving them the same amount of water won’t be enough to produce the same results as in the past at harvest time. UC officials describe the root zone salinity threat as a “sleeping dragon.”

Root zone salinity: A 'sleeping dragon' in almonds.

In the meantime, another dry winter and spring in 2015 has sped up almond development this season and Doll and other experts expect harvest time to arrive a few weeks earlier than usual. “We are having thicker hulls and smaller kernel size.”

On a positive note, Doll credits almond growers with becoming more in tune with their irrigation practices, working on ways to maximize their water distribution systems and putting in things such as pressure regulators and installing reservoirs.

 “I’m seeing a lot of innovation going on in orchards to make more efficient use of water,” Doll says. He recommends growers go online and download the UC ANR Publication No. 8515 titled“Drought Management for California Almonds.”

Lygus Tops Watch List for Valley Cotton Growers

Every season, we talk about the threat of lygus bugs to the cotton crop.

Well, this season it’s even more important than ever for growers to keep a close eye on this pest, especially during the squaring period.

Here is cotton square damage from lygus. - UGA photo

Field scout Carlos Silva reports an uptick of lygus bugs and lygus nymphs in the cotton fields.Some growers are already treating for the pest, fearing a heavy loss of squares and, in the long run, a drop in yield. Lygus is a constant threat from early squaring to final boll set.

The pest will pierce squares and damage anthers and other tissues, according to UC IPM. “When squares are less than 0.2 inch (5 mm) long, they shrivel, turn brown, and drop from the plant. Damage to larger squares may be to anthers, styles, and stigma, and may interfere with fertilization. If many squares drop, the plant may put its energy resources into vegetative growth, resulting in tall, spindly plants and reduced yields,” UC IPM adds.

Dr. Pete Goodell of UC IPM points out growers need to be even more vigilant to preserve as many squares as possible to protect their yield this fall because of the drought. Due to the uncertainty of water supplies later this summer, growers may wind up harvesting earlier than usual.

Lygus bug damage to a terminal. - UC IPM photo.

Carlos is snagging an average of one to two lygus bugs per 50 sweeps of his sweep net. In one field, he collected three to five lygusper 50. As a rule, UC IPM puts the treatment threshold at two per 50 from June 15 to 30.

Lygus bugs finds a home in alfalfa.

“Staying on top of lygus is a big issue right now,” Carlos says. For growers with nearby alfalfa fields, it is crucial they leave strips of uncut alfalfa during harvest to help keep lygus from fleeing into cotton. Remember, lygus prefer to live in alfalfa. “There is a lot of lygus in the alfalfa fields,”Carlos notes.

Meanwhile, Carlos says alfalfa growers are preparing for another cutting over the next couple weeks. One grower cut his crop a little early to minimize damage from weevils and worms.

  

In general, though, “pest counts have been pretty low in alfalfa,” Carlos says.

Hot Times a Time for Almond Growers to Stay Ahead of Game

 Hot, hot, hot and hot. 

Make it sweltering. Over the weekend and today, we had triple-digit temperatures – well above the normal 90-degree weather we get around these parts in late spring.

Young almond trees were whipping in the wind last week.

Sweltering weather, including more 100-degree weather Tuesday through Thursday, is taxing growers trying to stretch their water supplies. But what do you expect after the Valley experienced a wacky week of weather – hot temperatures, a little cooling, some gusty winds and a bit of precipitation.

Almond field scout Jenna Horine thought some young trees were going to snap in half as sustained winds on the Westside one day last week had them bending almost like towering palms caught in a Florida hurricane.

This heat wave can be problematic for almonds. Jenna notes the heat can trigger a mite outbreak. Already, she is finding some mite pressure on newer orchards on the Westside. These trees have a smaller canopy than the more mature trees and can be stressed even more by the hot weather.

During her scouting rounds, Jenna has spotted some orchards with “Do Not Enter” warning signs along the margins, an indication that these growers have treated their orchards. However, she says almond growers participating in the San Joaquin Sustainable Farming Project have held off pesticide treatment, opting to closely monitor their orchards for signs of pest pressures.

Heavy canopies can increase humidity in almond orchards.

However, some growers have applied fungicides to prevent diseases, indicating they are worried about scab and rust issues. Generally, late spring and summer rains, sprinkler irrigation and nearby waterways can create humid conditions in orchards. That’s because thick canopies caused by trees planted close together essentially trap the moisture underneath, Jenna points out. Unlike drip systems, micro-sprinklers will create a kind of mist and the warm conditions create humid conditions under the canopy.

Mist from sprinklers also can create orchard humidity.

Rust and scab are common diseases tied to excessive moisture.

Here’s what UC IPM says about rust: “The development of rust is favored by humid conditions, and the disease becomes worse when rain occurs in late spring and summer. Trees can be defoliated quickly when rust becomes severe. The rust fungus survives from one season to the next in infected leaves and possibly also in infected twigs. The disease causes leaves to fall prematurely and will weaken trees, reducing the following year's bloom if not controlled. Rust is often observed in second- and third-leaf nonbearing orchards where fungicides have not been applied.”

Rust is caused by humid conditions.           - UC IPM photo

UC IPM points out that orchards with a history of rust, should “apply sulfur or manebfive weeks after petal fall and follow four to five weeks later in late spring and summer with a Quinone outside inhibitor fungicide (FRAC Group number 11) to control leaf infections. Two or three applications may be needed in orchards that have had severe rust problems.”

On scab, UC IPM says: “severe scab infections cause early defoliation; if left uncontrolled for several years, infected trees become weakened. The disease often occurs in sprinkler-irrigated orchards where water reaches foliage.”

Scab can cause early defoliation in almonds    - UC IPM photo

“Scab may be controlled by shot hole sprays. However, a scab treatment may be required if rain occurs into mid- to late spring. One application as late as five weeks after petal fall can protect against scab, but an earlier application (two weeks after petal fall) may improve control. Scab resistance to quinone outside inhibitor fungicides (also known as strobilurins) has been documented; do not use FRAC mode of action Group number 11 fungicides in these orchards.”

Jenna reminds growers to be proactive and monitor their orchards regularly. “Stay ahead of the game,” she says. That investment in time will yield dividends at harvest time.

Field Day Alert: Here’s a final reminder about Tuesday’s Cotton Field day scheduled from 10 a.m. to 12:30 p.m. at the D&V McCurdy Farm, Highway 33 in Firebaugh. Cotton growers can learn valuable insights about insects and water and weed management from these speakers: Dr. Pete Goodell of UC Statewide IPM, Dan Munk of UCCE Fresno County, Kurt Humbree of UCCE Fresno County and Bob Hutmacher of the Westside Research and Extension Center. Mark the date on your calendar. For more information, contact Marcia Gibbs of the San Joaquin Sustainable Farming Project at (530) 370-5325. See you there.

Fallowing Fields to Stay Afloat During State's Historic Drought: Are More to Come?

For several years, we’ve talked about how farming is a tough business. To survive, you need to be resilient, adaptive and possess a can-do spirit. We have certainly seen that in recent years.

Some growers are diverting water from alfalfa to other crops.

Indeed, farmers weren’t discouraged by one dry year ... a second dry year … and even a third dry year – somehow managing to get enough water to survive financially in 2014. They learned to use water wisely and turned to more to drip systems and deficit irrigation practices.

But this fourth straight dry year is testing the limits of even the most seasoned veteran growers. Take some of the innovative farmers who have participated in the San Joaquin Sustainable Farming Project (SJSFP).

As we mentioned recently, one of the program’s growers opted to stop farming one if his alfalfa fields to divert precious irrigation water to a higher value crop. Now, another grower has called it quits after his third alfalfa cutting of the season and disc under the field, reports field scout Carlos Silva.

“Alfalfa takes up a lot of water for the season,” Carlos says. “The grower is going to use the water for his almonds.”

Grower Joe Del Bosque casts shadow over a fallow field.

Last week, another long-time Valley farmer and SJ farming project participant made a similar difficult decision, deciding to pull out his 70-acre asparagus field in the Firebaugh area. “We don’t have enough water to carry it from here on,” Joe Del Bosque told Your Central Valley.com

Unfortunately, we expect this same story to play out elsewhere in the Valley as we move into summer.

Carlos notes alfalfa growers have wrapped up the third cutting of the season, but it is anyone’s guess how many more harvests there will be left. Last year, growers managed to acquire enough water to make it through an entire growing season, which normally ends in the early fall.

“Everyone is trying to grow as much hay as possible this year,” Carlos says.

At least, there is some good news for alfalfa growers. Pests so far have been in check. Carlos is seeing a small uptick in alfalfa caterpillars and beet armyworms, but the numbers are nothing to be alarmed about right now.

The first irrigation of the cotton growing season is underway.

Speaking of water, cotton growers are starting their first irrigation of the season. “The crop is growing pretty fast. Some of the plants are getting pretty big,” Carlos says, noting that some plants are at eight to nine main stem nodes. Soon he will be keeping a record on fruit retention.

On the pest front, Carlos is finding some spider mites in the cotton fields. He’ll be keeping a close eye on these bugs.

  

Field Day Alert: Don’t forget about the Tuesday, June 16 Cotton Field day scheduled from 10 a.m. to 12:30 p.m. at the D&V McCurdy Farm, Highway 33 in Firebaugh. Cotton growers can learn valuable insights about insects and water and weed management from these speakers: Dr. Pete Goodell of UC Statewide IPM, Dan Munk of UCCE Fresno County, Kurt Humbree of UCCE Fresno County and Bob Hutmacher of the Westside Research and Extension Center. Mark the date on your calendar. For more information, contact Marcia Gibbs of the San Joaquin Sustainable Farming Project at (530) 370-5325.