Category: Coverage

All hort articles about achieving, confirming or correcting for spray coverage.

Pesticide Redistribution: An Important Aspect of Synthetic Pesticides
If you’re a sprayer operator with some experience behind you, you may have applied mercury arsenate, nicotine, Paris green, or perhaps even DDT. All of these historical pesticides were effective, but they were also toxic to both the applicators and the environment. Fortunately, today’s agrochemical manufacturers produce pesticides that are effective while being far less hazardous.
One important aspect of modern synthetic pesticides that enhances their efficacy is their ability to redistribute. Pesticide redistribution is the movement of a pesticide from its initial point of deposition to a different spot on or in the plant. Pesticides that can redistribute can improve pest control compared to those that must contact the target pest but cannot innately redistribute. This is especially true when spraying hard-to-wet plant tissues, such as flower clusters or fruit. Even when the immediate coverage of these tissues is insufficient, the subsequent relocation beyond the initial spray deposit can result in a more effective protective barrier. When plants are rapidly growing, many of these products can translocate through the plant tissues to protect newly emerged tissue that did not receive a direct deposit.
Some of the most difficult and persistent pests are more effectively controlled by redistributing pesticides. Materials that move within the plant after application provide improved control of piercing-sucking insects such as aphids and psyllids, as well as pests that feed in difficult-to-spray areas such as under leaves. These products can absorb into plant tissue, increasing their resistance to wash-off by rain or irrigation.
Five Types of Pesticide Redistribution
There are five significant types of pesticide redistribution: translaminar, vapor, xylem, phloem and redistribution via precipitation
Translaminar Redistribution
Translaminar redistribution (Figure 1) in its most literal sense is a compound moving from the side of the leaf that received spray, to the unsprayed opposite side. This results in protection on both sides. However, translaminar redistribution also involves limited radial movement providing a “halo” of protection around the initial deposition. The extent of this area of influence is product-dependent.
Figure 1. Schematic of translaminar redistribution, with small round dots indicating deposition of pesticide, arrows indicating the direction of redistribution, and the shading indicating the area of the plant protected by the pesticide.
Vapor Redistribution
Vapor redistribution (Figure 2A) occurs when surface depositions volatilize and move laterally along a plant surface, re-adsorbing to the plant surface in new locations as they move. Again, the extent of vapor activity is product specific, but also condition specific requiring an optimal combination of temperature, relative humidity, wind, and solar radiation to facilitate volatilization. When pesticides are referred to as “locally systemic,” it often implies that they exhibit translaminar and/or vapor redistribution properties.
Figure 2. Pesticide redistribution type schematics (A) vapor, (B) xylem, (C) phloem. The small colored groups of dots indicate deposition of pesticide, while arrows indicate the direction of redistribution, with shading representing the area of the plant protected by the pesticide.
Xylem and Phloem Redistribution
Xylem redistribution (Figure 2B), also called xylem systemic, refers to the absorption of a pesticide and subsequent systemic movement of the pesticide through the xylem vessels of a plant. Xylem vessels move water and minerals in an upward and outward direction in plants. There is very little movement of water and nutrients downwards or backwards along branches or leaves in xylem vessels. Xylem redistribution can help protect growing tissues from damage by pests or diseases when the pesticide redistributes from the point of application to the newly developing tissues. Most systemic fungicides and insecticides redistribute via the xylem.
Phloem redistribution (Figure 2C), also called phloem systemic, is the bi-directional movement of pesticides in the phloem vessels of a plant. Phloem vessels transport sugars and other nutrients both to the roots of plants and upwards and outwards to shoots and fruits/seeds. Phloem systemic pesticides are sometimes called “true systemic,” because they can translocate throughout the entire plant.
Some pesticides that redistribute via the xylem or phloem can be applied to the soil substrate to be absorbed by the roots and redistributed throughout the plant. The process of plant nutrients or pesticides being transported from one place to another within the plant is called translocation.
Soil-Applied Systemics
Several factors affect a pesticide’s ability to redistribute. These factors affect the speed of uptake, the duration and extent of translocation, and the amount of accumulation in plant tissue relative to the initial dose. For pesticides labeled for soil application, their uptake by plant roots and redistribution via xylem or phloem can lead to long residual efficacy of the product; Up to eight weeks or more depending on the product, plant, and soil. This is in contrast to foliar-applied products, where good residual efficacy could be expected to last two to three weeks depending on the product. However, foliar-applied products tend to provide a more rapid kill of target pests and a more rapid absorption and translocation of active ingredients.
For soil-applied systemic pesticides, the composition of the soil substrate can affect the uptake of the pesticide by the plant. Growing media high in organic matter (>30% bark or peat moss) can bind pesticides, making it difficult for plants to absorb them through roots and subsequently translocate via the plants vascular system. Soil applications of systemic materials should take place one to six weeks prior to the onset of the insect pest or pathogen. This allows sufficient time for the pesticide to translocate to, and accumulate in, target tissues. The more water-soluble pesticides (e.g. Thiamethoxam) are taken up more rapidly than the less water-soluble pesticides (e.g. Imidacloprid).
Redistribution via Precipitation
In contrast to systemic pesticides, contact pesticides cannot redistribute on their own. However, rain or irrigation can spread the deposit to some degree, increasing coverage area. This effect should not be relied upon, as it depends on the product formulation, the intensity of the precipitation, and the interval following application. In the case of prolonged precipitation, the residual activity of contact products can be greatly reduced as they are diluted and washed off plant tissues.
Plant Morphology
The status of the plant to which they are being applied is a significant consideration when applying redistributing pesticides. Both soil-applied and foliar-applied pesticides are more rapidly absorbed and redistributed when applied to young plants or juvenile plant tissue. In general, when plants are actively growing, have a strong root system, or are actively transpiring, they tend to absorb and translocate pesticides more rapidly than when plants are growing slowly. In addition, plants with difficult to wet leaves or surfaces due to thick cuticles or waxy layers tend to not absorb pesticides as readily. Penetration into plants with difficult to wet surfaces can be improved by adding adjuvants such as surfactants to tank mixes.
Multiple Modes of Redistribution
The extent to which each product can redistribute can be thought of as a continuum. Generally, when a product exhibits some form of redistribution, it can also redistribute via a different method. A good example of this is xylem and translaminar redistribution. When a product can redistribute via the xylem it generally can move through the leaf via the translaminar pathway as well. Some products can redistribute via the xylem, translaminar, and vapor pathways all at the same time. Others, while technically able to redistribute via more than one mechanism, are only biologically effective via one mechanism.
Consult the Pesticide Label and Other Reputable Sources
The best way to determine how a pesticide product redistributes is to consult the manufacturer’s label, as well as technical information from reputable sources such as government or academia. If a manufacturer provides a technical information bulletin it is generally available on their website on the pesticide product page along with the label. However, because there are no standardized metrics to rate pesticide redistribution, there can be significant disparity between products. Some products that are advertised as being xylem systemic for example, are actually less systemic than products that are not even advertised as being systemic. Additional information on the efficacy and redistributing characteristics of specific products can be obtained from extension agents or crop consultants.
Conclusion
In summary, when selecting a pesticide remember to consider the four different pathways of redistribution (xylem, phloem, translaminar, and vapor) and how these methods may improve the efficacy of your application, allowing you to get more out of every drop.
January 25, 2022
Coverage is King
We’ve often heard the adage “Coverage is King” but what does that mean, exactly? It means that in order for your spray application to yield acceptable results, a threshold amount of the active ingredient in your tank must end up on the target. But at what point have we achieved sufficient spray coverage without wastefully over-applying to the target? What does good coverage look like?
Let’s manage expectations right here at the beginning of the article: There is no single, definitive answer because it depends on the nature of the application. In other words, you have to understand which factors are relevant to your specific situation before you can understand what success looks like.
Let’s highlight some of those factors:
Transfer Efficiency, Catch Efficiency and Retention
This relates to the spray’s ability to span the distance from nozzle to target (transfer efficiency) get intercepted by that target (catch efficiency) and then deposit a biologically-active residue on the target surface (retention).
- First, the spray must reach the the target location. This may be the soil, or it might be the underside of a leaf deep in a plant canopy. The degree of success will depend on the droplet size(s), distance to the target and the environmental conditions.
- Then the droplets have to be retained by the target surface and not bounce or slide off. Difficult-to-wet surfaces such as fruit, stems and waxy vertical leaves may be more easily covered with finer droplets and/or formulations that include activator adjuvants (e.g. surfactants).
- Then the deposit must stay wet long enough to be absorbed by the tissue, or leave a hardy residue on the surface that can withstand weathering (e.g. precipitation, sun, and even bacteria) long enough to encounter the pest. More on this below.
Mode of Action
This relates to where spray must deposit (or relocate to) in order for it accomplish it’s objective. Here are a few examples of how products might work. Read your pesticide label to determine your situation.
- Some products require contact. Insects must touch them, either via a droplet landing on them or as they move through a deposit. Similarly, certain fungicides must contact fungal hyphae on the plant surface. A few products are designed to drench the target, as is the case with oil-based miticides.
- Some insecticides must be ingested. That may be in the form of a surface deposit or in plant material that has absorbed the chemistry. Similarly, some fungicides are absorbed by plant tissue.
- Many herbicides are mobile (i.e. systemic). They may be drawn up through the roots, or enter the cytoplasm via leaves and travel to the growing points on the plants, or move through the xylem. Others are contact, staying relatively close to the original deposit.
The sprayer operator should consider these factors when planning the application and when evaluating the resulting coverage. So how do we visualize coverage? Some operators look for the shine on leaves, or a cloudy residue once the spray has dried. That’s better than nothing, but we recommend water sensitive paper (WSP), which is still the most versatile and economical way to visualize coverage.
WSP can be purchased from most retailers that carry spray equipment. It is available in three sizes, of which the 1” x 3” size is the most common. It can be folded and clipped to a plant surface, or placed on the ground. We’ve written several articles on how to use it (such as here and here and in pretty much a third of the articles on Sprayers101).
There are two metrics that must be evaluated when assessing coverage on water sensitive paper:
- the area of the target that has spray on it, and
- the distribution of the droplets over that area.
Let’s use a metaphor to explain:
The Battleship® / Coverage Metaphor
Imagine the boats in this Battleship® game are the insect pests, and the board they’re on is a leaf. The white pegs represent the spray deposits. In this first image, we see 100% coverage and a very high deposit density. Sure, we got every boat, but this is literal and figurative overkill. There’s no need to completely drench the target in order to control most pests. When you spray a target past the point of run-off, you are not adding more pesticide to the target – you are displacing what was already there. The surface will not exceed the concentration of product you sprayed (with the possible exception of mixes that include certain adjuvants). While additional volume can improve coverage to a point, there is a diminishing return.
Unless the label specifically asks for a drench, this is too much coverage.
In this second image, we’ve covered about 15% of the target area, which is reasonable. However, note the lack of distribution. You can see that we’ve missed quite a bit of the leaf. If our pretend pests are sedentary and if this was a contact product, then we’ve missed. If this was WSP we would advise the sprayer operator to note how much space there is between the deposits. Could a pest such as an insect or small weed easily fit between the deposits?
15% coverage is good, but the distribution is bad.
In this third image, we are still covering about 15% of the target, but now the spray is distributed more evenly. Some of you are likely noticing that we missed a pest. That observation reminds me of one of my favourite exchanges from the movie “Christmas Vacation” where Clark finally got his house illuminated, but his father-in-law only sees the problems: “The little lights aren’t twinkling.” “I see that and thanks for noticing, Ed.”
15% coverage, distributed evenly. Deposits may have some pest activity beyond the edge of the residue (light red circles).
Yes, we still missed a pest, but spraying is playing a game of odds. You want enough spray to increase the odds of controlling a pest, but not so much to waste spray (and money and time). This image represents an ideal coverage situation. If this pest moves, or this pesticide redistributes even a little, it will affect the pest.
Plus, we should not discount the threshold of influence that lies around pesticide residue. Imagine a small circle around each droplet (illustrated here as light red haloes) where active ingredient may redistribute beyond the initial deposit to affect an adjacent pest. Perhaps even more importantly, deposits do not spread on WSP the way they do on actual plant tissue, so WSP always gives an underestimate of the potential coverage.
In this last image, we see that red deposits have been introduced. This represents a disease control program where an earlier (white) application retains some residual activity when next application (red) is applied. The second spray application almost never lands on top of the first, giving much more protection on the target. For those keeners out there, note that we got that last pest!
In the case of many disease management programs, subsequent sprays tend to fill in gaps left by previous sprays. If timing is prompt, residual activity will see you through.
If you Absolutely Need a Number…
So, what if you’ve read all this but still insist on a firm number to define adequate coverage? We’ll reiterate that there’s no universally-accepted threshold of deposit density or area covered. It would be nice if pesticide labels included this information, but they don’t.
We’ll stick out necks out and say that in general practice we see excellent results when we achieve 85 discrete deposits per cm² as well as 10-15% surface coverage on at least 80% of the water sensitive papers in a spray application. If you can manage this, it should give satisfactory results in most situations.
Ontario Agriculture Conference – 2022
For a really in-depth conversation on the topic of coverage, check out our presentation from the 2022 Ontario Ag Conference. We tried to deliver a fun and memorable demo at the end of this presentation to show how different droplet sizes might contribute to coverage. Enjoy.
January 18, 2022
Adventures in Lecturing – Turn Off PowerPoint
Harvest is mostly done and growers want to hear what we’ve learned and what’s coming next. Lecture season is upon us once again.
In 2021 we’re still finding our way through virtual conferences and hybrid models, but I like to think we’re slowly returning to the in-person format. Just last week I gave my first in-person talk in 20 months. It felt wonderful after having spoken into a dead-eyed camera for so long. Half-way through my lecture I remembered a lesson I learned a few years back and spontaneously decided to go off-script.
Let me explain.
In 2016 I was invited to present at the 40th annual Tomato Days conference in Southern Ontario. I knew what I wanted to say, but didn’t have a decent slide deck for that particular topic. I’d have to pull one together.
I work hard on my presentations. I employ lots of imagery (I create all my own illustrations). I get persnickety about fonts, white space and slide transitions. I try to tell a story that educates and hopefully, entertains. Prideful? Perhaps. But if you’re willing to sit on a hard chair for an hour, I’m going to do my best to make it worth your while.
I finished the slide deck, drove three hours to the conference, handed my USB data key to the organizers and sat down to wait my turn. It was a clear, bright winter morning and I saw that the pavilion we were in was more-or-less windows and a roof. It was so bright, in fact, that none of the 150 attendees could see the projector screen!
I watched sympathetically as the first speaker spent 30 minutes trying (and failing) to verbally describe his graphs. I cringed as the second speaker pantomimed her illustrations in some kind of brave, interpretive dance. Then it was my turn.
I decided I wasn’t going down that road.
When the moderator brought up my talk, I turned the useless projector off. I asked the squirming and disinterested audience:
Q. “What’s the most terrifying thing you can do to an academician?”
A. “Take their Power Point away.”

For the next 30 minutes we had a discussion about spray coverage. No props. No slides. The audience slowly warmed up to the new format. They shared experiences. They debated. They asked questions. I became more facilitator than speaker.
When our time was up I think everyone was pleased. Sure, I missed a lot of my key points and never really addressed the subjects I thought I would, but who cares? Everyone learned something.
For me, I learned that speakers should abandon the script every now and again. It’s not always ideal since we’re there to teach and structured visuals are often required. But, the next time you’re asked to speak, consider the possibility of using your time to engage your audience and establish a dialogue… not just talk at them until the moderator gives you the 5-minute warning.
I have a colleague who does this masterfully. Whenever he is the last speaker on the agenda, and the previous speakers have discourteously gone over-time and whittled his time in half, he jumps straight to his take-home slide. He leads a quick discussion with the audience and becomes a hero. The moderators are now back on schedule and no one is late for lunch.
Since “Tomato Days”, I now try to do this once a year. I never know when the mood will take me, but when it does I give the audience a choice: They can hear my canned presentation or I can shut it down and we can have a conversation. To date, given the option, every audience has opted to go off script. It’s scary, it’s fun and like I said earlier, everyone learns something.
I challenge you to try it the next time you’re lucky enough to be in front of an audience in person.
November 29, 2021
Spraying Asparagus in Fern
This research was performed in 2012 and since then there have been considerable advances in application technology for asparagus in fern that should be considered. Be sure to read the epilogue at the end of this article.
Introduction
Diseases such as purple spot can have major economic impacts for asparagus growers, and the best line of defence is spraying the appropriate control products. The good news is that asparagus growers know this. The bad news is that there are few things harder to spray than asparagus in fern.
Asparagus infected with purple spot.
Asparagus in fern can stand 1.5 m (5 ft) high by 1.0 m (3 ft) diameter and is typically planted on 1.2 m (4 ft) centres. Asparagus in fern has a very dense canopy full of needle-shaped leaves. This dense canopy slows air movement, making conditions still, humid and very difficult for a spray droplet to penetrate.
Spraying asparagus in fern.
Spray coverage is a combination of two factors: the area of the target contacted by spray droplets, and the distribution of spray droplets over that target. For most insecticide and fungicide applications, reasonable coverage is reflected by 10-15% surface area covered paired with an even distribution of approximately 85 medium sized droplets per square centimeter. This is not a rule, but a guideline.
In order to determine the best way to spray, we have to be able to compare the coverage achieved. To do this, we used water sensitive paper, which is yellow until contact with spray turns it blue. Three sets of three targets were placed in approximately the same location for each pass.
Water sensitive paper arranged on stands, ready to be placed in the fern.
Water sensitive paper orientation and location in asparagus canopy relative to sprayer direction.
We tested five popular nozzle types, at two ground speeds using three carrier volumes to answer three questions:
1. Does spray volume impact spray coverage?
2. Which nozzle style gives the best coverage?
3. Does travel speed impact spray coverage?
Does spray volume impact spray coverage?
Five different nozzle types were used to spray three volumes onto the targets at 16 kmh (10 mph). This was repeated three times and target coverage was determined both as droplet deposits per cm² (see Figure 1) and total % covered (see Figure 2).
Figure 1. Average deposits per cm^2 for five different nozzle types at 187 L/ha (20 US gpa), 234 L/ha (25 US gpa) and 280 L/ha (30 US gpa) at a ground speed of 16 kmh (10 mph).
Figure 2. Combined average percent coverage for five different nozzle types at 187 L/ha (20 US gpa), 234 L/ha (25 US gpa) and 280 L/ha (30 US gpa) at a ground speed of 16 kmh (10 mph).
Cards in each position consistently received a significantly higher average deposit per cm² and significantly higher average percent coverage at higher spray volumes. The relatively low coverage in the middle position was anticipated given the orientation of the targets to the sprayer.
Therefore, it would appear higher volumes result in better coverage, at least up to 280 L/ha (30 gpa). Generally, there is a threshold where exceeding a given carrier volume results in a diminishing return.
Which nozzle gives the best coverage?
Coverage from five different nozzles was compared: the Hollow cone, Flat fan, Dual flat fan, Guardian Air and Air-induced hollow cone. Given that 280 L/ha (30 gpa) resulted in the best coverage, the following figures illustrate droplet deposits per cm² (see Figure 3) and total % covered (see Figure 4) at 280 L/ha (30 gpa).
Figure 3. Average deposits per cm^2 for five different nozzle types at 280 L/ha (30 US gpa) and 16 kmh (10 mph).
Figure 4. Average percent coverage for five different nozzle types at 280 L/ha (30 US gpa) and 16 kmh (10 mph).
The graphs show that each nozzle followed a similar trend, with more droplets at the top of the canopy, less or par at the bottom of the canopy, and considerably less in the middle of the canopy (which is not surprising given the orientation of the target around the stem).
The trend in droplet density from highest to least coverage is:
1. Hollow Cone
2. XR flat Fan
3. Guardian Air
4. Dual Flat Fan
5. Air Induced Hollow Cone
The percent coverage data was less clear. The top two nozzles for each position were:
Top Target:
1. Guardian Air
2. All other nozzles approximately the same
Middle Target (around the stem):
1. XR flat Fan
2. Hollow Cone
Bottom Target:
1. XR flat Fan
2. Hollow Cone
It can be argued that the target at the top of the canopy is easiest to spray, and therefore does not have as much importance as the middle and bottom targets. As such, it would appear that the XR flat fan and Hollow cone nozzles give the best overall coverage. It is debatable whether the higher droplet count from the Hollow cone is more important than the higher percent coverage of the XR flat fan.
Does travel speed impact spray coverage?
Hollow cone nozzles and XR flat fan nozzles were used to spray targets at two travel speeds and three volumes. Target coverage was determined both as droplet deposits per cm² (see Figure 5) and total % covered (see Figure 6).
Figure 5. Average deposits per cm^2 for Hollow cone and XR flat fan nozzles at 280 L/ha (30 US gpa) and either 8 kmh (5 mph) or 16 kmh (10 mph).
Figure 6. Average percent coverage for Hollow cone and XR Flat fan nozzles at 280 L/ha (30 US gpa) and either 8 kmh (5 mph) or 16 kmh (10 mph).
The variability in deposit density and percent coverage from medium/fine droplets created by the hollow cone nozzles make it difficult to determine statistical significance, but the trend suggests that higher ground speeds improve coverage in the middle and bottom of the canopy. This is likely due to the wake of the sprayer and the vortices created by its passage stirring fine droplets into the canopy.
Overall recommendations
The data suggest that coverage was improved when the sprayer travels at 16 kmh (10 mph) rather than 8 kmh (5 mph). Coverage was also improved at higher spray volumes, where 280 L/ha (30 US g/ac) provided the best overall coverage for all nozzles. As for the best nozzle, this depends on the application; the hollow cone created higher droplet densities than the XR flat fan, but the XR Flat fan created higher percent coverage. Higher droplet densities may be preferred when controlling disease with contact products, but spray drift becomes a significant concern. Higher percent coverage might be preferred with locally systemic products where complete coverage is less of a concern and preventing spray drift is a priority.
Epilogue
This work was performed in 2012. Since then there have been significant advances in sprayer design for spraying asparagus in fern. Dr. Torsten Balz (Bayer Application Technology Manager) kindly provided an example of such a sprayer (see below) and a video link to watch it in action. Drop arms that bring the nozzles closer to the target at all canopy depths are an ideal solution as long as the row spacing allows clearance without snagging the drops. Further, there have been developments regarding the use of hollow cones in an overhead broadcast application. Over- and under-laps in the hollow cone swath lead to double-dosing and gaps respectively that are referred to as “Technical Strip Disease”. Combined with considerable drift potential, hollow cones are not recommended.
Air-assisted drop arms greatly improve coverage uniformity in asparagus in fern. Photo kindly provided by Dr. Torsten Balz.
Special thanks to Max Underhill Farm Supply (Vienna, Ontario) for use of their sprayer and their assistance both spraying and placing water sensitive papers in the field. Thanks to Mr. Ken Wall of Sandy Shore Farms Ltd. (Port Burwell, Ontario) for providing the site and hosting the associated workshop, and thanks to TeeJet Technologies for their donation of parts and supplies.
June 3, 2021
OrchardMAX
OrchardMAX won the 2016 Canadian Agri-Marketing Association’s “Certificate of Merit” in the Mobile Apps Category.
2022 Update
OrchardMAX was developed in 2016. iOS and Android have moved on since then, so the links to the app no longer function. Maintaining this app for new operating systems requires a capitol expense which, presently, we have not explored. If you have some interest in exploring the model, reach out to jason@sprayers101.com and we’ll send you a copy that will work on Excel.
What is OrchardMAX?
OrchardMAX is a free app developed by the Ontario Ministry of Agriculture, Food and Rural Affairs to improve sprayer efficiency and effectiveness in apple orchards. The app is based on the Crop-Adapted Spraying (CAS) model, which was tested in semi-dwarf and high-density apple orchards in Ontario and Nova Scotia from 2013 to present day. The primary goal of the app is to help the sprayer operator achieve consistent coverage, no matter the architecture of the orchard block, throughout the season. Research has demonstrated that following the process improves coverage while reducing wasted spray by an average of 20% over the season.
OrchardMAX will:
- Accept Metric or US Imperial units
- Create an inventory of your orchard airblast sprayers
- Create an inventory of your orchard blocks
- Determine optimal sprayer settings based on the average size, shape and density of the trees in the block
- Propose a pesticide dose for each block, including ideal nozzle rates, water volume and product(s) per tank
- Develop a permanent spray record that can be emailed to the user for archival
- Calculate work rates and estimate productivity
OrchardMAX won’t:
- Exceed label rates
- Calibrate your sprayer
- Confirm spray coverage
- Account for environmental conditions such as wind, humidity or temperature
- Advise a volume below 400 L/ha (about 42.5 US g/ac)
- Advise a dose that is less than 1/2 the label rate (that may seem low, but consider a first-year planting)
Recognizing that this app can only approximate ideal sprayer settings based on data entered by the user, sprayer adjustments are still required on the part of the sprayer operator. Specifically, the sprayer operator must still calibrate and adjust the sprayer air to match the tree and the environmental conditions and confirm coverage using water-sensitive paper.
Why you should try it
Financial savings: The app will help you match your sprayer settings to the crop you’re trying to protect. That means you will find out if you are over- or under-spraying the tree canopy and by how much. This information, combined with feedback from water-sensitive paper, will improve canopy coverage and very probably improve the quality of the apple crop. Additionally, the app may lead to reduced pesticide volumes, which reduces environmental contamination and saves money.
Explore different spraying scenarios: Perhaps you’re considering a new planting and you would like to know how many tanks it would take to spray an orchard block for a given speed, or row spacing. Perhaps you are considering a sprayer with a larger tank to reduce the number of refills, or a smaller tank to prevent rutting and you want to see how that affects your spray efficiency. Maybe you’re considering decreasing your fill time by using a tender or nurse truck. Enter the parameters and see how it affects your spray day BEFORE you invest.
Create permanent spray records: The app will create a library of spray records that are emailed directly to you.
How it works
Enter Farmer/Owner information
Like any new practice, you have to put in a little time and effort to realize the full benefit of the app. Try it on a few blocks in the first year, make the changes to your spray program and review the results. As you get used to this new method for spraying, and see the improvement, you can continue to expand its use to the entire operation.
First you have to enter information about your operation. This only has to be done once.
1. Enter your profile information
2. Complete the Inventory
3. Information for each sprayer in your operation
4. Information about each sprayer operator
5. Information about each physiologically different orchard block (e.g. Trellised Gala on 10′ rows is quite different from mature semi-dwarf Empires)
Now you are ready to calculate rates for a spray day.
1. Choose the Sprayer, Operator and Block from your Inventory
2. Decide if you want to use label-rate, or an optimized rate based on tree size
3. Determine if you will spray every row, or alternate rows (You cannot choose to optimize your rate AND spray alternate rows)
Select sprayer, operator and block from inventory, then enter spray-day data to calculate rate and sprayer settings.
Enter information about the tree shape and density (This accounts for pruning and time-of-season). This is mostly visual, where the user chooses from a series of pictures
- Enter label rate and preferred rate for each pesticide in the spray mix
The software then lets you know how much carrier and/or pesticide can be saved if you nozzle your sprayer according to it’s prescription.
- From a nozzle catalog, enter the nozzle rates for each position within 5% of OrchardMax’s prescription
The software then assembles a simple spray record, including all the rate adjustments and sprayer settings, which is emailed to you for your permanent records.
Where can I get it?
Select your operating system (images below) and you will be taken to the respective store and begin downloading. Please rate the app so we know it’s being used and can work to improve it. Please opt in to provide us with usage information so we can see how it’s being used – this is entirely private, and we will not contact you.
NOTE: These links may no longer function. Contact jason@sprayers101.com if you’d like to learn more about the model or to try the Excel version.
The OrchardMAX app was developed by AgNition Inc. with funding from Growing Forward 2.
February 25, 2021