Navel Orange Worm: Crop Value Damages & Tips for...

Mon Nov 20, 2017 @ 5:11 AM

September Almond Report

Fri Sep 22, 2017 @ 11:09 AM

August Almond Report 8.25.17

Fri Aug 25, 2017 @ 10:09 AM

August Almond Report 8.11.2017

Fri Aug 11, 2017 @ 10:09 AM

Wed Nov 30, -0001 @ 12:00 AM

July Almond Report

Wed Jul 12, 2017 @ 10:07 AM

June Almond Report

Mon Jun 12, 2017 @ 10:06 AM

Monte Vista Farming and Growers Take Japan

Wed May 17, 2017 @ 9:05 AM

April Almond Report 4/26/17

Fri Apr 28, 2017 @ 11:05 AM

April Almond Report

Tue Apr 11, 2017 @ 5:04 AM

Brendan O'Donnell Takes Dubai

Mon Mar 20, 2017 @ 4:03 AM

March Almond Report

Mon Mar 13, 2017 @ 11:03 AM

February Almond Report

Fri Feb 10, 2017 @ 10:02 AM

CEO Jonathan Hoff Goes Back To School!

Tue Jan 31, 2017 @ 8:01 AM

January Almond Report

Thu Jan 12, 2017 @ 10:01 AM

CEO Recap: A Review of 2016 and Projections for...

Fri Dec 30, 2016 @ 10:01 AM


Fri Dec 23, 2016 @ 10:12 AM

The Land iQ Acreage Tool and New Position Report...

Tue Dec 13, 2016 @ 11:12 AM

Happy Thanksgiving!

Fri Nov 18, 2016 @ 3:12 AM

Almond Report

Thu Nov 10, 2016 @ 2:12 AM

Sometimes I’m not sure if we’re selling...

Tue Oct 11, 2016 @ 2:12 AM

Bill and Hillary Just Saw Our Average...

Sat Sep 24, 2016 @ 2:12 AM

First Position Report of 2016

Fri Sep 09, 2016 @ 2:12 AM

Almond Report

Fri Sep 02, 2016 @ 2:12 AM

It’s time for positive thinking!

Thu Aug 11, 2016 @ 1:12 AM

It's Harvest Time!

Thu Aug 04, 2016 @ 1:12 AM

Almond Report

Thu Jul 07, 2016 @ 1:12 AM

It's Time...Another Marketing Year in the Almond...

Fri Jun 17, 2016 @ 1:12 AM

Almond Report

Fri May 27, 2016 @ 1:12 AM

What Is Happening in the Almond Industry? A Recap...

Thu May 19, 2016 @ 1:12 AM

Push! Push! Get those prices up!! We’re nearly...

Thu May 12, 2016 @ 12:12 PM

What Time Is It?

Thu May 05, 2016 @ 12:12 PM

Almond Report

Fri Apr 22, 2016 @ 12:12 PM

Almond Report

Fri Apr 08, 2016 @ 12:12 PM

Almond Report

Mon Mar 14, 2016 @ 12:12 PM

Almond Report

Wed Feb 24, 2016 @ 11:12 AM

Market Timing - The Dangers of Getting Caught...

Thu Jan 28, 2016 @ 11:12 AM

Almond Report

Fri Jan 15, 2016 @ 11:12 AM

Almond Report

Tue Jan 12, 2016 @ 11:12 AM

Almond Report

Mon Jan 11, 2016 @ 11:12 AM

Almond Board of California Crop Projected...

Wed Jul 01, 2015 @ 12:01 PM

Pallet Tracking Ensures Safe and Timely Delivery

Mon Jun 29, 2015 @ 10:57 AM


Navel Orange Worm: Crop Value Damages & Tips for Prevention

The 2017 Crop harvest has brought a lot of discussion about navel orange worm (NOW) damage, likely causes, impact to crop value, etc.  













There are a million articles with information about control measures, factors which influence NOW pressure, IPM, etc., and most of them contain far more scientific information than what you are about to read below (that is, if you make it past the first paragraph). But, rather than dragging you through the syllabus for Entomology 101, I’ve provided a detailed explanation of how NOW and other insects can impact a crop’s value, quality, marketability, etc., in order to help quantify the potential impact and to highlight the importance of a quality pest management program. I will also give a quick list of some of the things we and our growers consider to be KEY components of a solid NOW control program.  I’m not a PCA, and the information below is not intended to replace the advice you get from your PCA or CCA. Rather, it’s to provide intel on some of the approaches that have been successful with us. Your PCA is still your best source for information regarding materials, chemistries, and products designed to match your specific situation. 

Let’s start by taking a look at the ways navel orange worm and insect damage can impact the value of your crop: 













While there are several markets throughout the world that will take product with high levels of chip/scratch, broken, and even doubles, you’d be hard pressed to find markets or end users willing to accept products with excessive insect damage. In fact, the allowable limits for Serious Damage according to the USDA (a category which includes insect damage, decay, rancidity, and damage by mold) range from 1% (U.S. Fancy No. 1) to 3% (U.S. No. 1 Pieces). The most common grades which include U.S. Extra No.1, U.S. No.1 Supreme, and U.S. Select Sheller Run (SSR), have a narrower tolerance which ranges from 1.5% to 2%. It’s also important to note that while these limits are set forth by the USDA, customer expectations can be quite different, and much tighter. The USDA grades haven’t changed in the last 25 years, while customer and consumer expectations for quality and food safety have changed dramatically…



Most of you are aware that some varieties (most notably nonpareil) can earn a sizable premium over the kernel market if they are sold in the shell. India, the Middle East, and China (for different reasons) provide major demand for Inshell. In some cases, the premium for inshell product shipped into one of these markets can be as high as $0.20/kernel pound when to compared non-inshell/kernel markets! That’s great news, right? Well…it is, unless you have high insect damage. In China, the max allowable insect damage percentage is 2%. In India, it works a bit differently - since they shell the almonds by hand, workers can remove insect damage and sell the good kernels. Therefore, they can take a higher percentage of rejects, but only pay for the good kernels (less insect damage). However, once you exceed 4%, or so, serious issues can arise including customer claims, infestation while the goods are on the water (pre-shipment fumigation helps, but is not perfect), along with a number of other things. Bottom line is, high insect damage will eliminate your chances of earning inshell premiums on your Nonpareil…



It’s not uncommon for product which is heavily impacted by NOW damage to also have high levels of Aflatoxin. Several markets, including Europe and Japan, have STRICT limits for Aflatoxin levels, and require pre-shipment (and sometimes post arrival) testing. Needless to say, the presence of aflatoxin due to NOW damage can create serious sales constraints…


Market timing

As you all know, timing the market correctly is key to earning maximum value for your crop. When NOW or other types of insect damage are introduced, timing the market becomes problematic. We have to spend additional time cleaning product, and usually have to blend it in slowly with higher quality goods in order to dilute serious damage levels below allowable limits. This slows down the rate at which we can sell products, and limits our ability to time the market. In years like 2015 when selling a lot early (pre-October) meant the difference between $5/lb. and $3/lb., this can equal HUGE opportunity costs…


Impact on Yield 

As most of you know, insect damage is deducted by the USDA from your incoming weight. In other words, although an orchard may produce 2,800 lbs./acre, the effective NET yield will be 2,800 lbs. less inedible pounds (insect damage is classified as inedible by the USDA). So, at 5% insect damage, the effective net yield would be 2,660 lbs./acre (2,800 x 95%), a reduction of 140 lbs. At $3.00/lb., that is $420/acre. 


Value Summary

Now that we have addressed some of the ways that NOW/insect damage can impact crop value, lets boil it down to some specific examples. We’ll focus on Nonpareil because it’s generally the highest volume/value variety and NOW impacts Nonpareil in several of the above-mentioned ways. 


Example #1

In this example, we are making several assumptions which reflect likely circumstances.  By that, I mean that we are assuming normal, stable market conditions similar to what we are seeing now during the 2017 crop. The second example will use more extreme circumstances similar to what we experienced during the 2015 crop. Keep in mind that the info in both examples is ultra-simplified for illustration purposes only. I realize 0% insect damage is highly unlikely, and that I am not adjusting for other factors such as foreign material, chipped/scratched, etc. All figures are per acre. In each example, there are two columns – we’ll call the left-hand column #1 and the right-hand column #2. Column #1 assumes 2500 lbs./acre with no insect damage. Because of the lack of insect damage in column #1 we are also assuming that we can make inshell out of about 65% of those kernels. On some years, we can exceed 75% with very clean, dry input product from the field. We are also assuming that since insect damage is so low in column #1, we can market the kernels as Extra No. 1 with no NOW caused market constraints, therefore, the kernel value used in column #1 is $0.15/lb. higher than that used in column #2. Column #2 assumes 4% insect damage. Because if this there is a 4% reduction in yield and zero pounds of inshell created. A 4% insect damage is borderline for inshell, so there is a possibility that we would still be able to make some, however, this is the “likely” example and we are keeping it simple. We will look at more extreme circumstances in Example #2. Keep in mind, these figures relate to market value differences and do not account for any additional charges a packer may levy against product with high serious damage. So, you can see below, that the economic impact of 4% insect damage equates to nearly $1,000 per acre of lost value or opportunity cost (OVER 14%!!)



Example 2

Below is a more extreme version of example #1. We are still assuming a baseline yield of 2500 lbs./acre, but we are adding a few more extreme circumstances including a market timing component. During the 2015 crop, growers who delivered product with high insect damage not only felt the double impact* of not being able to make inshell and selling lesser quality kernels, but also the effect of missing the market all together. Growers with high quality product were able to sell early during the PEAK of the market, and therefore, achieved kernel pricing at or near $5/lb. Again, I realize that it’s nearly impossible to sell all of your crop at the PEAK of the market, but give me a break…i’m trying to make an extreme example. Since product with excessive NOW damage takes time to clean up, and more time to sell, the example below assumes we missed the peak of the market, and the kernel sales suffered from both quality challenges (we use 8% insect damage in the “extreme” example below) and “market rot”. You can see that in this circumstance the value impact or opportunity cost per acre exceeds $5,600 (47%!!!!!).


Even though Example #2 seems far-fetched and perhaps too extreme, trust me, it actually happened. The point is, market timing is critical and insect damage makes it nearly impossible to get right.

So now that we’ve illustrated the potential economic impact NOW and insect damage can have on a crop, let’s look at a few things to keep in mind when developing a plan to control insects. I highlighted the word “plan”, because that is exactly what it should be, development and execution of the plan should start EARLY. Once you fall behind, it’s very hard to catch up.


NOW Prevention 

Mummy nuts should be removed from almond trees to reduce the potential for NOW infestations (photo cred: Almond Board of California) 








Winter sanitation

Obvious, but critical: Nut’s left in the field after harvest are perfect targets for late flights of adult NOW to lay eggs which will eventually hatch into larvae, feed on the nut, build a cocoon over-winter, then hatch into adults. To remove them, winter shaking followed by “blowing strips” or sweeping mummy nuts into windrows when possible, then eventually mowing with a flail mower to destroy them is most effective. Sounds simple, but a lot of things need to happen to get all this right. Winter shaking works best when mummy nuts are wet. Morning dew, light rain, and fog all provide perfect conditions for easy and effective winter shaking. Of course, damp conditions also make it tough to get through orchards with heavy soil or steep terrain. Keep this in mind when developing your plan. You should start early enough to lower the risk of shaking next year’s buds off of the tree. In late January when buds start to swell and become larger/heavier, a lot more of them will fall when shaken. So, if possible, earlier-is-better (notice an “early is better” theme?). Further, when developing your winter sanitation plan, you need to be thinking about things like pruning and brush removal/disposal. It’s hard to get a shaker through an orchard with brush stacked in the center of the rows. In older orchards, it’s best to prune early, and to stay on the top of your orchard shredder’s list. 


TIP: I find that a case or two of Keystone Light** enjoyed with the guy who does your brush shredding goes a long way towards keeping your orchard high on his list. For younger orchards, we like to wait until spring time to prune anyway, in which case, you can complete winter sanitation before pruning. Don’t forget, you still need to blow them, then mow them in order to complete the loop.


Traps, Phenology Models, and Biofix Date

Rather than go into entomology 101, I’ll keep this short and to the point. Be sure that your PCA is monitoring both adult trap counts and egg trap counts and establishing a biofix date in the spring. Make sure that traps are in the field EARLY enough to capture the first egg laying event of the season. Also, make sure he/she is keeping an eye on phenology models in order to predict the next hatch and most effective spray timing for control of subsequent generations. This involves monitoring degree day accumulation starting at the biofix date (the date at which NOW eggs start to appear in traps). 


Spray timing

The phenology models along with advice from your PCA should provide some insight on spray timing. 

o    May spray: We like to start control of NOW in May by adding material which targets NOW (and PTB) to our May mite spray. We like to start just a little earlier than the models suggest and to bracket spray. Cover everything 50% (every other row) quickly, then go back and get the other 50%. We find that widens the coverage window.


o    Hull Split: Same as May spray above. Start a little early, and bracket spray. Nuts never split all at the same time.  We like to start a day or two after blanks start to split


Spray coverage and material

o    Coverage: Make sure your sprayers are calibrated and that your ground speed isn’t too fast. Going fast with low volume gets you through the orchard faster, but we find speed can impact efficacy in a big way. A 2-mph speed seems to work well at 50 gal./acre. It’s slow, but at 50 gallons, you can cover 10 acres which cuts down on your number of loads/tanks, and still get good treatment and coverage. At 100 gal./acre, 2.5-mph should work fine. Both will work, just stay away from higher speeds and lower rates. Also, don’t go cheap on your sprayer and make sure your tractor (for PTO driven sprayers) has plenty of HP’s to spin the fan/pump at desired RPM. A good sprayer that generates plenty of wind is critical when it comes to covering the entire tree all the way through the canopy.

o    Coverage and bracket spraying: Bracket spraying can help get spray material where it needs to go at hull split. When hull sutures first open, the area within which NOW adults lay eggs is fairly small, and therefore, easy to cover. As hull split progresses, and sutures become wider, it is more difficult to cover the entire opening, and its especially challenging to get material inside the hull where some eggs may be located. Getting 50% (every other row) done right when split starts, then going back for the other 50% is a good way to be sure you are hitting your target.

o    Material: Consult your PCA on what material you should be using. Just keep in mind that some materials can impact beneficial insects. Pyrethroids may do a good job of killing adult NOW, but they will also impact other insects that may be helpful in controlling mites. Kill all the beneficial insects, and you may see a flare up of mites later in the season

o    Mating disruption pheromones – We don’t have a lot of experience using mating disruption, but a few of our growers have had success. My advice would be to treat mating disruption pheromones as a supplement to your pest management plan, and not as a replacement for other control measures.   

o    Neighbors: We have heard a lot of growers blame their neighbors for their own issues related to insect damage, and while neighbors can certainly be hosts to large populations of NOW (and others), they are rarely the actual cause of wide spread damage. If you are next to a pistachio orchard or a crappy, rarely cared for almond orchard, just plan accordingly. Multiple applications to areas near the problematic orchard may be necessary.


So, to sum things up: Build a solid plan and stay ahead of it. Once you are behind, it’s hard to catch up. Also, don’t cut corners. Controlling NOW may be costly, but not controlling NOW is FAR MORE EXPENSIVE. If you bite the bullet and invest in a good control plan, you will be rewarded with a high-quality crop, better yields, and overall better return-per-acre. 


NOW is the main focus of this article because of its status as a prolific almond pest. However, keep in mind that your plan should also address PTB, leaf-footed plant bug, ants and other pests that can impact your crop, and that many of the same principles should apply to the control plan for those pests.

NOW and other insect damage can wreak havoc on a crop. Going the extra mile every year can help ensure that things never get out of control. Let us know if you have any questions. We are always here to help.


* Double Impact is a 1991 action movie starring Jean-Claude Van Damme in which he plays a dual role as two twin brothers separated at birth, and re-united in Hong Kong. One pretty boy, one bad boy, two total bad asses… 

** If your orchard shredding provider scoffs at Keystone Light and/or prefers higher quality spirits, he is probably charging you too much.