Monday, September 22, 2014

A Successful Defoliation Strategy Brings in More Green



The green flag is out for the start of cotton plant defoliation in the Valley.
Keep out: Defoliated field.

Field scout Carlos Silva reports seeing some fields already defoliated and anticipates more growers to follow suit over the next week or two. Experts consider defoliation as the last big management effort that will impact the cotton crops financial bottom line this season.

Defoliants are used to boost leaf drop and drying of the plant, which increases the timeliness and efficiency of the harvest. Growers that terminate their crop early are often trying to head off potential sticky cotton damage caused by burgeoning white fly or aphid populations.
Successful defoliation can improve cotton grades by lessening staining and trash, make harvesting faster, speed up drying, delay boll rot and even boost boll opening.

Conditions are right to start defoliating cotton fields.
Here’s what UC IPM considers the best conditions for defoliation:
  • Moderate to high air temperatures (daytime greater than or equal to 80 degrees, nighttime greater than 60 degrees)
  • Relatively low plant and soil nitrogen levels
  • Moderate soil water levels (plants not water stressed)
  • Relatively uniform crop development; plants at vegetative cutout with limited or no regrowth
  • Weeds, insects, and diseases under control
  • Ability to get good chemical coverage and penetration of the chemicals into the plant canopy
Pest control advisors and UC extension specialists can offer recommendations about defoliant products and application rates.

Meanwhile Dr. Pete Goodell of UC IPM says PCAs are telling him that white flies weren’t a problem this season. No one can cite a specific reason.

Carlos agrees. “Last year, we had a lot of white flies. We haven’t seen very many white flies or aphids (this year). They are pretty much under control.”

Plants are  already drying only 12 hours after defoliation.
Even so, Pete repeats his mantra that growers shouldn’t relax and continue to watch for these crop-threatening pests until the fiber is picked and headed to the gin.

To illustrate his point, he offered this anecdote to the online publication Ag/Fax this: “We still need to follow this insect all the way through. You absolutely can't walk away from that field until there's nothing left but the stalks. We've had plenty of reminders this month about the attack on September 11, 2001, and that stands out as a year when we had a lot of sticky cotton. Remember: after the attack the government grounded aerial applicators for about 2 weeks. PCAs had written recs for defoliation, but nobody could make applications. That left fields out there on their own for 14 days with very little monitoring, and white fly took advantage of the situation.”
  
Field Day Alert: Almond growers will receive valuable post harvest management tips from UCCE Merced’s David Doll and UCCE Fresno’s Gurrett Brar on Tuesday, October 7 in Los Banos. Sponsored by the San Joaquin Sustainable Farming Project, the event will be from 10 a.m. to noon at the corner of Mercy Springs Road and Cotton Gin Road. Continuing education and CCA credits will be available. For more information, contact Project Director Marcia Gibbs at (530) 370-5325 or  marcia@sustainablecotton.org
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Monday, September 15, 2014

It Is Best to Leave the Sticky Cotton at the County Fair



It was a year ago when California cotton growers faced the worst white fly infestation in a decade. That sent chills through the industry.
Sticky cotton is a major industry concern.

The fear: sticky cotton, which is caused from honeydew secreted by white flies and cotton aphids. At stake was the global reputation for California’s high quality cotton, Fortunately, growers took action to avert a potential sticky cotton disaster.

How serious is this issue?

A 2007 USDA report called sticky cotton a worldwide program that is “increasing as cotton processing machinery is refined because high-speed, large-volume processing of lint requires cleaner cotton. Much of the cotton produced in the Western United States is exported, and loss of export markets is a serious threat to the U.S. economy.”

In California, growers spent $220 million to combat sticky cotton from 1992 to 2001. Studies indicate sticky cotton can result in a price reduction of 3 to 5 cents a pound.

Aphids damage on a cotton plant.
That’s why field scout Carlos Silva and Dr. Pete Goodell of UC IPM continue to remind growers to keep alert for white flies and aphids. These pests “will jump on you when you least expect it” Pete says.

Let’s remember this: The only good sticky cotton is the kind you get at the county fair.

Honeydew residue caused by aphids
Right now, Carlos reports an uptick in aphids in some fields. The hot weather could help these pests reproduce faster. Already some areas have worrisome hot spots that could require treatment soon. 

Those who need to treat for these pests should remember to ask their PCA about using softer materials that won’t impact beneficial insects. You want to preserve biological controls and let natural predators gobble up the aphids.


Cotton bolls are opening up nicely.


Meanwhile, the string of triple-digit temperatures is expected to continue through early this week. That should speed up boll opening. We could see some growers starting to defoliate their fields over the next week.

 Cotton Tour Alert: The ever-popular Cotton Farm Tour through the San Joaquin Valley will Thursday, October 30. Again the price is right: Free. Space is limited for this behind-the-scenes look at the many sides of cotton production. This year, lunch will be at the Cardella Winery in Mendota.  Check the Sustainable Cotton Project website for more information.


Monday, September 8, 2014

Cotton May No Longer Be King, But It Has a Place in the San Joaquin Valley's Kingdom



As a long-time UC extension cotton specialist, Dr. Bob Hutmacher has seen plenty of highs and lots of lows in the state’s cotton industry.

Cotton expert Bob Hutmacher
The face of California agriculture has certainly shifted from the days when cotton was king. Now grapes and almonds are the state’s top crops commodities. Indeed, the three straight dry years have contributed significantly to the further erosion of cotton acreage.

The recently released August crop forecast by the USDA’s National Agricultural Statistics Service in California illustrates the slide: Upland/acala cotton production in California is forecast at 220,000 thousand bales, a decrease of 34 percent from last year. Harvested acreage is estimated at 64,000 acres, down from 109,000 a year ago – a 41 percent decline. (Before the drought, acreage was 189,000 in 2011)

The NASS forecasts pima cotton production 500,000 bales, down 18 percent from last year. Harvested acreage is estimated at 149,000 acres, down from 169,000 acres in 2013 – a 21 percent drop. (Before the drought, acreage was 259,000 in 2011.)

Despite the slide, Hutmacher remains confident that “cotton has a fit” in California’s farmscape. Remember more than 90 percent of the nation’s American pima is grown in the Golden State.

Moreover, Hutmacher says cotton – unlike other crops like almonds or lettuce – can do fine even when water is in short supply and water quality is poor, especially if it comes from a well. “It is one of the most salt tolerant crops. You can use poorer quality water on cotton and use better quality on other high value crops,” he says.

Cotton growers have wrapped up their final irrigation of 2014.
Another plus is cotton plants respond well to water stress. For example, let’s say growers cut back on water by 50 percent. The yield won’t drop by half. You’ll get a partial reduction in yield – probably around 40 percent.

Hutmacher points out more cotton growers are getting into deficit irrigation. They are dropping at least one irrigation this season. In Kern County, Hutmacher sees some growers cutting out two to three irrigations on cotton, diverting that water for other crops such as tomatoes and garlic.

Hutmacher credits growers with implementing best management practices to maximize their cotton production. In other words, it’s profit per acre that counts. That should keep cotton part of the fabric of California agriculture.

Meanwhile, field scout Carlos Silva says the final cotton fields were irrigation in the past week as we head into the back stretch toward fall harvest. He looks for defoliation to start over the next few weeks.
  
Green lacewings are beneficial bugs.
So far, aphids and white flies remain under control. But Carlos advises growers to stay alert for these pests. Let your guard down and aphids or white fly populations could surge. To boost the beneficial insect population, Carlos released green lace wings in a number of fields.  We don’t want to see growers grappling with sticky cotton problems.








Monday, September 1, 2014

Following a 3-Legged Approach for a Successful Cotton Crop This Season



 Experts say fast-food giant McDonald’s based its tremendous worldwide growth on a three-legged stool business model. The combination of three things – operators, suppliers and employees – provided the foundation to success.

You might same cotton growers rely on a three-legged approach to achieve a successful harvest: Monitoring square retention in the spring to guide lygus pest management strategy; monitoring nodes above white flower to determine cut-out in mid-summer and the end of lygus monitoring in mid-summer; and monitoring nodes above cracked boll (NACB) to establish the time for defoliation around early fall.

Right now, growers are on the third leg and headed on the back stretch toward harvest time. Most have completed the last irrigation of the season, according to field scout Carlos Silva.
Carlos says bolls are starting to open up on the bottom quarter or third of the plants. He anticipates growers will start defoliating their fields soon.

Like last year, harvest expects to arrive a couple weeks earlier than usual, according to growers. You might see the first harvesters roaming the fields in late September in some locales.
In this final stage of plant monitoring, the average number of nodes above cracked boll helps growers time defoliation and determine potential yield loss and the loss of fiber quality in immature bolls, according to UC Integrated Pest Management. 

Here’s what UC IPM says: Ideal timing for defoliation occurs when unopened harvestable bolls are an average of four or less nodes (including missing branches) above the highest first position cracked boll. If it becomes necessary to defoliate a field prematurely at an average of five NACB because of a honeydew-producing insect infestation, a yield loss of less than 1 percent will occur; at six NACB the loss will be less than 2 percent.

UC IPM recommends growers pick five plants randomly from four areas in each field. Select plants that have a cracked boll on the first position fruiting branch (see the chart). Then find the top cracked first position boll and use this as “fruiting branch zero.” Count the number of nodes above the fruiting branch zero until reaching the uppermost harvestable boll on the plant. This boll should be large and mature enough to be able to open before the scheduled harvest date. The number of nodes counted above fruiting branch zero is the NACB. To calculate NACB, take the total number of nodes above cracked boll and divide them by the total number of plants sample (20).
  • Four NACB is used as a target for the first harvest aid in Upland/Acala
  • Three NACB is used as a target for defoliant timing in Pima
UC IPM offers more information about cotton plant monitoring on its website.

On pest front, Carlos reminds growers to turn their attention to aphids and white flies now that lygus bugs are no longer a threat. While aphids and white flies are mostly in check at the moment, growers need to remain vigilant to prevent an outbreak that could lead to sticky cotton problems.

In the alfalfa fields, pests also are under control. Growers have finished irrigating and are now preparing for at least one more harvest this month. This is good news. It’s turning out to be a fairly normal season for alfalfa, an important commodity for the state’s dairy and cattle industry. Because of the drought, growers had been worried that they would come up short on water and end their season as early as June. Fortunately, they have been able to get additional water to extend their season through the summer.

In the orchards, almond field scout Jenna Horine says early varieties, primarily nonpareils, are pretty much harvested. Last week, she spotted some farm crews heading into the orchards with hand poles to knock the leftover nuts off the trees. It’s not too early to get those mummy nuts off and avoid problems with navel orangeworm next year. Kudos to these growers.



Pole used to knock off mummy nuts. (UC IPM photo)