Cotton Harvest on Final Stretch; Farm Tour Gets Up Close and Personal

With the on-again, off-again rainy weather lately, growers have been scrambling to harvest their cotton. So far, about three quarters of the Valley’s cotton acreage has been harvested, University of California experts told us during our annual Cotton Tour last week.

Acala is in. The Pima harvest is still out with growers hoping to get out into the fields and complete their second and final picking soon.
On Friday, we had more wet weather with rainfall totals overnight ranging from 0.1 of an inch to a half-inch in various parts of the region. More rain could raise concerns about mold developing in the harvested cotton. Let’s hope for a little wind and dry weather in the coming days. Weather forecasters are predicting more rain by the end of the week.

Cotton Tour participants get a chance to pick some cotton.

Fortunately, we had nice sunny weather during our farm tour – one of the best ever with lots of people attending – from students, to apparel company representatives to U.S. Department of Agriculture officials. During the all-day tour, we saw a nice perennial hedgerow at Windfall Farms, cotton harvested at George Bettencourt’s farm and saw- and rolling gin in action at Silvercreek Gin. We had lots of good questions: “How many people does it take to harvest cotton?” “How many acres of cotton are harvested per hour?” And “what is the difference between organic cotton and Cleaner Cotton™?’

Tour participants were treated with Indian Summer weather.

We explained our growers produce Cleaner Cotton™ without applying the most toxic chemicals used in cotton production. They follow biological controls and Integrated Pest Management practices – something that can save money for growers and help protect the environment. We pointed out that in California it isn’t economically viable to grow organic cotton because of high labor and input costs. I think many people on the tour came away with a better understanding of Cleaner Cotton™. They also left with a better appreciation for farmers and the cotton industry.

Cotton: The Case of the Missing First Squares

As I travel around the Valley, I’ve been noticing an unusual trend in many cotton fields.

The plants are at the seventh or eighth node, or true leaf, and showing the first pinhead squares. In all my years of scouting, though, I’ve never found so many first squares missing on young cotton plants. The first square location is important and can impact profits in the long run.  Losing the first square position causes the plant to become more vegetative and experience problems retaining fruit.

   I’m seeing missing first squares in 20 to 30 percent of the cotton fields that I’m scouting this season. In the past, the highest rate 5 to 10 percent of the fields.

   The squares are nibbled off by pests we had this spring. The growing      season is eight to 10 days behind schedule.

   Some growers irrigated too soon and ended up lowering the soil     temperature, which affected plant development. UC IPM is a good resource to learn about monitoring early squaring in cotton growth and development.

   Of course, this plant condition is worrisome to growers. Some might be tempted to apply growth regulators such as Pix, which are designed to increase boll retention and cut back vegetative growth.  Regulators can reduce yields if applied when plants are going through stressful, especially moisture-related, conditions. They also can lead to stunted plants, which could prompt growers to increase nitrogen into the soil to help the plants grow taller for easier harvest in the fall.

Determine the reasons why the first squares are missing. Some pest control advisors might want to start treating for lygus now.

Remember to keep monitoring the fields for pest pressures and be familiar with the surrounding fields. If you’re growing safflower nearby, you might want to treat it for lygus. If you have alfalfa, let borders or strips to prevent migration of worms and lygus. You could treat the alfalfa strips rather than the cotton field.

Lacewings are natural enemy to aphids.

Meanwhile, I’ve spotted some aphids in the cotton fields. Natural predators such as ladybugs and lacewings could take care of small problems. Spot treatment is another alternative.

I am starting a weekly release of 10,000 to 15,000 lacewings for each field I’m scouting to control the aphids.

Field Day Alert: I will participate in our Cotton Pest Management Field Day on Thursday, June 30 from 10 a.m. to noon at the Bettencourt Farm in Mendota. The featured speakers: Dr. Pete Goodell of University of California Statewide Integrated Pest Management at the Kearney Ag Center on managing lygus and Dan Munk, UC Cooperative Extension farm advisor and cotton specialist, on plant development and its role in IPM. Check our Sustainable Cotton Project website for directions. It’s sure to be extremely informative and give growers an opportunity to meet cotton experts directly.

                        

Ants Are Out on a Limb in Almond Orchards

Editor’s note: This week’s post is written by guest blogger Kevin Parkinson, almond field scout for the San Joaquin Sustainable Farming Project.

Most of us know by now that ants can cause significant damage to almond crops once the nuts have been shaken to the ground (see “The Almond Doctor” May 2, 2010). But something that many do not realize is that ants may begin to be a problem at hull split if the lower limbs of the almond tree are touching the ground.

Photos by UC Statewide IPM Program.

 If your limbs are touching the ground at this point in the season or you have a history of ant damage, the best thing you can do is monitor for ants following the guidelines of the University of California Statewide Integrated Pest Management program for ants in almonds and treat if necessary.

Result of ant damage in almonds.

To prevent ants from climbing limbs in future seasons, make sure limbs are pruned high enough off of the ground to prevent them from touching the ground with a full crop of almonds.  Remember: Ants do not climb up the trunks of almond trees.  If you have ants attacking nuts while still in the tree, they are climbing up limbs that are touching the ground.

On a final note, you should know that not all ants are bad.  Many are beneficial.  Check out this guide to help you identify common ants found in almond orchards.

Bug Counts Up: Time for Border Strips in Alfalfa fields

There’s one way I can tell when the spring will begin getting warmer and sunnier. The bugs start coming out.

With daytime temperatures now in the upper 70s and low 80s, I’m starting to see more pests in the alfalfa fields. Specifically, looper worms and alfalfa caterpillars are showing up in greater numbers as I scout various fields around the San Joaquin Valley. I’m also noticing lygus counts are on the way up.

Monitor  for  looper  worms.      Photos by  Jack Kelly Clark

Last week, my sweep net collected an average of 5 to 7 worms for every 50 sweeps in the alfalfa. That’s up from an average of 1 to 3 worms the previous week. So far, the sampling indicates were in a safe mode, which means the pest pressure isn’t great enough to warrant pesticide treatment. As the days grow warmer, I expect the pest numbers will increase.

Right now, most growers are preparing for the second cut of alfalfa. A few are even poised for their third cut. The recent rains had growers on edge and mulling the timing of their next harvest.

It’s never too early to think about creating border strips. It’s good to have small strips of uncut alfalfa this time of the year. I recommend a leaving quarter swath – roughly a 2 to 3 feet wide strip – at the end of the field. These strips will retain loopers, alfalfa caterpillars and lygus, preventing them from migrating to nearby fields and damaging those crops, especially cotton. Alfalfa strips also will attract natural enemies such parasitic wasps.

Keep an eye out for alfalfa caterpillars in the fields.

This farm management practice can save time and money because you’re holding off spraying pesticides until absolutely necessary. That’s where field monitoring and pest sampling comes in. Here’s a rule of thumb: Consider treatment when after 50 sweeps per stop, you collect 10 or more alfalfa caterpillars, or 15 armyworms, or a combination of 10 alfalfa caterpillars and armyworms. I usually make 3 to 4 stops in each field.

In early summer start sweeping fields with adequate plant height 2 to 3 times per week to monitor for caterpillars and continue through fall.  Early cutting will give satisfactory control if the infestation appears late in the cutting cycle.
Combine monitoring of armyworms with monitoring for alfalfa caterpillar as described in Alfalfa Caterpillar and Armyworm Monitoring. Count and record the number of healthy and parasitized caterpillars caught in your sweep net on a monitoring form (68 KB, PDF).
If cutting is not practical or not scheduled soon after monitoring, treat if there is an average of 10 or more nonparasitized alfalfa caterpillars (those not infected by parasites) per sweep, 15 or more nonparasitized armyworms per sweep, or 10 or more nonparasitized alfalfa caterpillars and armyworms combined per sweep.

When you need to spray, consider selecting from a variety soft pesticide materials on the market. They’re effective and good for the environment. Talk to your pest control advisor about the available materials, especially those that won’t harm beneficial insects.

There are great resources available from the University of California Statewide Integrated Pest Management program. Check out UC IPM’s website for more tips about pests and alfalfa.