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Coping with the Tripple Whammy

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Two-dollar-a-gallon diesel fuel. Soaring electric rates – when power is available. Rapidly rising costs of fertilizer, farm chemicals, machinery, labor, insurance – everything a grower buys. Deep cuts in water allocations. And the lowest farm commodity prices in recent memory. The summer of ’01 won’t soon be forgotten.
Rising costs, critical shortages of essential inputs, and low farm prices have combined for a triple whammy on California growers.

“I’ve been farming since 1974 and I’ve never seen an era like this,” says Art Bowman, Blue Diamond grower and partner in Salida Ag Chem.

Gerry Rominger agrees. The Arbuckle grower and Blue Diamond board member says, “In years past, from time to time, we’ve had a high fuel price or high fertilizer price or low almond price, but this year everything from both ends is hitting us at once. All of my inputs are expensive and everything I sell is cheap. It’s a squeeze. I don’t think that’s ever happened to this extent before.”

To be sure, California almond growers are experiencing one of the most difficult cost-price squeezes in history. The price side of the equation is the result of another in the almond industry’s long series of boom and bust cycles. Rising costs of inputs are the result of an unusual combination of events that will, like the imbalance in almond supply, work itself out over time.

Growers who remember the ‘70s and ‘80s know that good and bad times come in cycles. Every time that almond supplies and consumption have gotten out of balance, consumption eventually caught up to crop production and grower prices returned to profitable levels. That process is underway now, as Blue Diamond, the Almond Board and other handlers work to expand almond consumption in the U.S. and abroad.

In every market cycle since 1910, your cooperative has spearheaded sales growth and the long-term development of the almond market. With your continued support, your cooperative will again lead the way back to profitable grower returns. Meanwhile, Blue Diamond has cut operating costs and increased efficiency at all levels – improvements that will strengthen your bottom line.

Blue Diamond, along with other farm organizations, is also working hard to ease the strain in the water and power markets. We make your needs known to the policy makers and monitor progress toward resolving those issues.

The current crisis will pass, but in the meantime we have to deal as best we can with the difficulties that this triple whammy has dealt us. This article and those that follow in future issues of Almond Facts will offer tips on how to maximize your returns, minimize your crop production costs and maintain crop quality while protecting the future productivity of your orchard. We welcome your feedback and ideas that can be shared with your fellow growers. Contact your field supervisor.

Wresting Water Woes

Tips on when and how to reduce water use

A lighter-than-normal Sierra snow pack and below-normal precipitation for most of the state combined for tight water supplies for agriculture and power production in 2001. According to official reports, the state averaged just 75 percent of normal for all precipitation for October 1, 2000 through March 2001. But runoff projections for the important watersheds of the west slope of the Sierra that produce water and power for agriculture ranged from a scant 46 percent of normal on the American River to a high of just 63 percent on the Tuolumne River. The Upper Sacramento watershed managed to accumulate a 74 percent of normal supply. The bottom line for many irrigators is that 2001 will be a very challenging year.

The major state and federal projects announced updated water allocations in March that did little to encourage their customers. The Central Valley Project announced that agricultural contractors north of the Sacramento-San Joaquin Delta will get 60 percent of their base allocation while those south of the Delta will get only 40 percent.

The State Water Project, which had announced a 25 percent allocation at the beginning of the year, increased that to 30 percent on the strength of better-than-average precipitation in February. Local districts with their own supplies have widely varying allocations.

Growers who have ample groundwater available to augment their surface supplies may make it through the growing season with little or no strain – assuming they get enough power (or diesel) to run their pumps as much as they would like. Others, such as growers on the west side of the San Joaquin Valley, who have little or no useable groundwater and only a 30 percent allocation from the State have a serious challenge, says Blake Sanden, irrigation specialist with Kern County Cooperative Extension. Many of those growers have told Sanden that they are reducing their row crop acreage in order to have more water for their orchards.

Except for the fortunate few who have ample supplies of water with little or no requirement for pumping, 2001 presents a water-management challenge to stretch the available supply to make a crop not only this year but assure one for next year, as well, while minimizing pumping expense.

Fortunately there are water-management tools available to help cope with this challenge. Growers who haven’t already done so can adopt a water budget or follow the advice of university researchers on deficit irrigation of almonds. The conclusions drawn from field trials of various deficit irrigation regimes could prove useful this year, as might some of the following ideas on testing irrigation system efficiency and minimizing power costs by maximizing pumping efficiency.

Adopt A Water Budget

If a little bit of something is a good thing, more is better. That’s a common line of reasoning. But in a dry year, more may not be possible. Water supplies being as low as 30 percent of normal in some areas leaves little or no wiggle room, making cautious allocation of a scarce resource imperative.

Tim Jacobsen of the Center for Irrigation Technology at California State University, Fresno, says, “Some growers tend to over-irrigate. The reason they do is because it is easier than applying the correct amount of water. The thinking goes, if you are going to err, err on the side of too much, not too little. With limited water supplies this year, now would be a good time to adopt a water budget to minimize waste and maximize results.”

Water budgeting helps growers know when, how much and how to irrigate. It aims for optimum irrigation levels by matching irrigation applications to the needs of the trees and soil water holding capacity.

“Using readily available programs, you calculate your outgo – your ET, how much water your trees are using under current atmospheric conditions – and how much your soil will hold in the root zone,” Jacobsen explains. “Then you irrigate to refill the root zone by figuring how much water to apply and at what rate.”

Setting up a water budget takes some time and effort, but once the initial work is done, it is relatively easy to maintain and pays big benefits in crop performance and irrigation efficiency, Jacobsen says.

To obtain more information on water budgeting contact your farm advisor or visit Wateright on line at www.wateright.org or the Department of Water Resources California Irrigation Management Information System (CIMIS) site at www.dwr.water.ca.gov.

Deficit Irrigation

If it appears that you may not have a “normal” supply of water this year, you may want to consider adopting a deficit irrigation regime. University researchers have found ways to stretch limited supplies while minimizing damage to crops or trees. Their advice could be useful not only this season but for the next few years. Drought conditions often last for several seasons, so the long-term effects of reduced irrigation should be considered.

Sanden, the Kern County Extension irrigation specialist, advocates an approach that limits crop losses in the current year to 10- to 15-percent kernel weight shrinkage while protecting next year’s crop. This approach, based on university research, places any necessary water stress in the pre-harvest period while giving full irrigations post-harvest, in September.

The Crucial Factor

“Regardless of how much water a grower has,” he says, “the single most important thing an almond grower can do to help preserve next year’s crop is to put on a minimum of 6 inches, preferably 9 inches, of water in a couple of post harvest irrigations.”

Don’t worry about putting on water early in the season, he counsels. “What you do not want to do is irrigate at 100 percent early in the season, then cut it off 40 or 50 days before harvest.”

Recommended Regime

“If someone tells me he has only 2 feet of water to work with, my recommendation is to irrigate at a 50 percent deficit until the first of July, about three weeks before irrigation cut-off for normal harvest,” Sanden says. “In the first week of July pump the soil profile back up with 4 to 6 inches of water, then cut off irrigation about two weeks before harvest. Then, if he can, if he has micro-sprinklers or a drip system, he should put on an inch or inch and a half of water in between the Nonpareil and pollinator harvests. After picking up the pollinators, he should put on the rest of the water.”

Sanden offers some other advice: “A two-week harvest cut-off is okay if a grower can put on 3 or 4 inches of water the first week of July. The bare minimum is a 50-percent deficit irrigation until harvest cut-off. But if you follow a 50 percent deficit regime all the way without a boost in early July, don’t cut off irrigation until 7 days before harvest. Then put on the 6 to 9 inches post-harvest. If you follow this program, you will probably lose 10 to 15 percent in shrinkage, but you’ll assure yourself of a crop next year.”

Field Trial Findings

Sanden bases his advice on a four-year deficit irrigation study in which university researchers looked at long-term effects on almonds of applying reduced amounts of water at different times of the growing season. The effects of the different regimes varied greatly.

The researchers concluded that “with reduced irrigation supplies, irrigation timing plays a pivotal role in maximizing kernel yield, both in the stress year and the following season.” As a result of their study, the researchers recommend “biasing the stress to the pre-harvest period, since it maintains fruit load, albeit at the expense of kernel size,” while assuring a good fruit load the following season. The critical finding, they said, is “severe post harvest stress must be avoided.”

The project was led by Dr. David A. Goldhamer, Extension Irrigation Management Specialist at the Kearney Agricultural Center. His collaborators were Mario Viveros, Kern County Farm Advisor; Beth Teviotdale, Extension Plant Pathologist, and Walt Bentley, Extension Entomologist, Kearney Ag Center. They conducted their tests in a mature orchard on microsprink-lers near McFarland in Kern County.

Almond Stress Tolerant?

The research team set out to determine if there are periods during the growing season when almond trees are relatively tolerant of stress. Their methodology, called regulated deficit irrigation (RDI) purposely stresses trees at specific times of the season. If their assumption that almond trees can tolerate well-timed stress proved correct, they would be able to recommend a regime that, in a normal water year, would save water without reducing nut yields or quality. And in a drought year, a successful RDI program would minimize the impact of severely restricted irrigation on the current and future crops.

Goldhamer and his associates experimented with three seasonal irrigation amounts, each applied with three different stress-timing regimes and compared these with a control. The orchard’s potential water use (ETc) was about 39 acre-inches per acre. The three experimental deficit irrigation levels were 22, 28 and 34 acre-inches per acre.

The “A” treatment imposed the stress primarily before harvest while reserving some water for post-harvest irrigation. In the 28-inch or 30-percent deficit irrigation regime, the A trials received 100 percent of the normal amount of irrigation in March and April, 50 percent of normal May through July, and 100 percent of normal August through mid-October, with a 50-percent application the last half of October.

The “B” treatments did just the opposite, emphasizing pre-harvest irrigation with relatively little water for post-harvest. The B plots in the 30 percent deficit regime received 100 percent of normal irrigation through May, 50 percent in June and July, 100 percent August through mid-September, and finished the season with a 50 percent application in late September.

The “C” treatments stressed the trees all season long. These orchards received 70 percent of normal March through mid-November.

In the 22-inch regime, the A treatments got 100 percent March through mid-April, 50 percent mid-April through June, none the first half of July, 50 percent the second half of July through mid-August, 100 percent the second half of August through September, and 50 percent the first half of October. The B treatment received 100 percent through mid-April, 50 percent from mid-April through July, 100 percent through August, and finished with a 50 percent application in early September. The C treatment received 55 percent March through mid-November.

To enhance hull split and successful flower bud development, the team took care – regardless of the seasonal irrigation amount – to provide as much water as possible in the 4-week period just before and after harvest in both the A and B regimes.

Result: Avoid Post-Harvest Stress

While different irrigation levels and stress timing influenced kernel size, there was little variation year to year, the team reported. But the different treatments greatly affected nut load. The B and C treatments in the 22-inch and the B treatment in the 28-inch regimes produced significantly lower nut loads in subsequent crops. Goldhamer said that they attribute the decline in nut load in those treatments “to stress during the post-harvest period interfering with reproductive bud development. Our earlier work showed that post-harvest stress reduces fruit set the following season.”

“There was a strong correlation between 1995 pre-dawn leaf water potential (an indicator of stress) in early-mid-October and 1996 fruit load,” he added. “This reduction in fruit load due to post-harvest stress was primarily responsible for declining kernel yields with time in the B and C treatments.”

Crop Effects Vary

Kernel Size: The size of kernels declined regardless of stress timing with the most severe deficit irrigation, the 22- and 28-inch treatments. Kernel size reduction was greatest with the A treatment that emphasizes pre-harvest stress in order to reserve more water for post-harvest irrigation. The C treatment that stresses trees all season long affected kernel size the least.

Nut Load: The A treatments (most water post-harvest) had the least impact on nut load. In fact, says Goldhamer, the A trials had slightly higher nut loads than the control in the most severe – 22- and 28-inch – treatments.

Kernel Yield: Yields from year to year in the 22- and 28-inch treatments were least affected by the A regime, and were most reduced by the B regime. There were no statistically significant differences in yield for the 34-inch regime compared to the control. The C treatment had the highest yield of the test regimes, identical to the control.

Unusual Relationship

For most crops, the relationship between yield and plant water use (ETc) is assumed to be linear, says Goldhamer. “For example, reducing water use by 30 percent would suggest that yield would be reduced by 30 percent.”

But Goldhamer’s team discovered that this straight-line relationship does not apply to almonds. “For example, a 45 percent reduction in ETc (the 22-inch treatment) with both A and C timing regimes reduced kernel yield by 15 percent,” he explains. “A 30 percent reduction in ETc reduced kernel yield by less than 10 percent with the A and C regimes.” But the B treatment resulted in yield reductions more like those expected in a 1:1 yield to water use relationship.

Save Some for Post-Harvest

The clear conclusion of the deficit irrigation study is that front-loading your irrigation and leaving nothing for post-harvest is not the way to go. The best yields over time came from orchards that were stressed in the pre-harvest months but received full irrigation post-harvest. This strategy resulted in no reduction in nut loads; any reduction in yields was due to smaller fruit size.