Category: Boom Sprayers

Main category for sprayers with horizontal booms

  • Ecorobotix’s ARA Sprayer: A targeted sprayer that’s finding its place in Ontario vegetable fields

    Ecorobotix’s ARA Sprayer: A targeted sprayer that’s finding its place in Ontario vegetable fields

    Targeted spraying is a technology that enables the site-specific application of plant protection products and liquid fertilizers based on sensor readings. Some of the latest machines incorporate computer vision and processing capabilities that can distinguish between different types of weeds and crops based on multiple adjustable criteria.

    The Swiss-made ARA Sprayer by Ecorobotix, has recently generated significant interest among Ontario growers. This article provides a technical overview of the machine, including a detailed explanation of its main features and capabilities.

    The Sprayer

    The sprayer is a two-component system, mounted directly onto the front and back of a tractor. The front unit consists of two separate tanks: one dedicated to the chemical solution and the other to fresh water, which can be used for rinsing or refilling the chemical mixture tank. The front component also includes the pump and processing unit (Figure 1).

    Figure 1- Front-mounted unit.

    The boom section is mounted via three-point hitch to the rear of the tractor (Figure 2). The shrouded boom folds for transport and storage and features 156 individually controlled nozzles (Figure 3).

    Figure 2- Rear unit deployed.
    Figure 3- Closeup of the boom.

    The unit can be controlled and monitored from a tablet or smartphone connected through the machines’ own Wi-Fi. External data connection through internet is only required for occasional maintenance and updates but not for regular field operations. Regardless of the complexity embedded in the smart operating system, the interface is intuitive and easy to manage. Most of the parameters are automatically optimized by the software (Figure 4).

    Figure 4- Tablet interface.

    Capabilities

    Since the intelligent vision system acts as the central controller for each individual nozzle, it enables a wide range of operating modes and potential applications. Depending on user needs, the system can process information and respond in various ways. The following list outlines the currently available and tested features, which may be expanded in the future.

    Banded Spraying

    In this mode, parallel bands of variable width are sprayed, which might include or exclude the crop (Figure 5), depending on the objective. The lines are defined based on AI detecting a planting pattern, which will lead to the automatic definition of the spraying swaths.

    Figure 5- Banded application options: in-row or inter-row.

    Size-Exclusive Spraying

    This option allows targeting the spray based on the plant size. It can either be used to:

    • Detect and spray weeds larger than a small emerging crop.
    • Detect smaller emerging weeds in an advanced-stage crop. Weeds similar in size or larger than the crop will be missed in this case. (see figure 6 – left).
    • Spray only the crop with fertilizers or pesticides when no-specific algorithm has been developed to differentiate it from the weeds. The crop must be significantly larger or smaller than the weeds for this mode to work efficiently. (see figure 6 – right)
    Figure 6- Only plants smaller (left) or larger (right) than a specified target are sprayed.

    Green on Brown Spraying

    The machine will spray all detected green material (Figure 7). This is particularly useful for improving chemical use efficiency in stale seedbed and insecticide applications. It also offers an interesting option to reduce the risk of herbicide carryover in pre-plant, post-weed-emergence control, especially when weed cover is low and the product may persist in the soil long enough to affect the crop.

    Figure 7- Green on brown spray.

    Green on Green Spraying (Six Scenarios)

    The vision system and processing capabilities can identify the crop, distinguish it from weeds, and selectively target either, regardless of plant size. Additionally, a variable safety buffer can be defined to determine how close a spray can be applied to the nearest crop leaf. If this feature is inactive, any overlapping weeds will be sprayed, even if the herbicide contacts the crop. If active, the sprayer will avoid targeting weeds that are closer than the defined safety buffer distance, which can be set up to 16 cm (6.3”).

    The parameters can be configured to cover six difference scenarios:

    1. Selective herbicides when no safety buffer is required

    All weeds will be sprayed, regardless of their proximity to the crop. If they’re very close, the crop might receive part of the spray (Figure 8). This mode is suitable for selective herbicide applications.

    Figure 8- Herbicide application with zero safety buffer.

    2. Non-selective herbicides when the contact with crop canopy should be minimized

    In this case, depending on the potential damage caused by the chemical contacting the crop, a variable buffer can be programmed. Only weeds that can be sprayed while maintaining the defined buffer distance from the crop will be targeted (Figure 9). Inevitably, weeds in very close proximity or overlapping with the crop will be missed.

    Figure 9- Weed target spray with a safety buffer.

    3. Crop-targeted spray

    The machine will detect the crop and will not spray anything else (Figure 10). This can be useful for insecticide or foliar fertilizer applications.

    Figure 10- Crop-targeted spray.

    4. Application of weed pre-emergence herbicides post-crop-emergence

    In this case the entire surface, except the crop canopy is sprayed (Figure 11). It can be utilized to spray herbicides with soil residual activity post crop emergence.

    Figure 11- Pre-emergent herbicide application excluding the crop/

    5. Monocots vs dicots weeds differentiation

    This mode is limited only to onion fields for now. It can be configured to spray only monocots weeds (grasses, sedges) or only dicots weeds (broadleaf). This can be useful to increase the efficiency of post-emergence broadleaf or grass selective herbicide applications.

    6. Specific weeds targeted

    In this mode only the target weeds will be sprayed. As of now, it’s only available for thistles, docks, and common ragwort. It can be used when a specific herbicide is used to target hard-to-control species.

    Speed and Accuracy

    For all applications, the company claims to have a spray accuracy of 6 cm by 6 cm (2.4”x2.4”). The speed of operation will be dependent on the weed size. The larger the weed size, the lower the recommended speed to allow for an optimal spray coverage of the weeds, increasing the treatment efficacy. The speed operating range is 0 to 7.2 km/h (0-4.5 mph).

    Weed coverage or density does not affect the maximum recommended speed, as the machine can process images at such high rates that it is capable of scanning and spraying 100% of the area when moving at full speed. In other words, the processing unit does not need to slow down to detect, differentiate, and target weeds, even when they are present at very high densities.

    Ecorobotix claims the machine can cover 2.8-3.2 ha (7-8 acres) per hour under typical conditions and can run 24/7 independent of light conditions.

    Crop Portfolio

    As of August 2025, the company has developed the following algorithms for specific crop recognition:

    Vegetable Crops:

    • onion
    • carrot
    • lettuce
    • endive/chicory
    • beans
    • spinach
    • broccoli (beta)
    • cauliflower (beta)
    • leek (beta)
    • other cabbages (beta)
    • potatoes
    • sweet corn

    Field Crops:

    • sugar beet
    • rapeseed (canola)
    • corn
    • soy (beta)
    • cotton (beta)
    • wheat (beta).

    For the crops not listed, the equipment can still be used but not with the features that required crop identification for targeted sprays.

    Technical Specifications

    • Minimum weed size required for weed detection: 4 x 4 mm.
    • Maximum plant height: 40 cm.
    • Minimum crop size for proper identification: at least two true leaves.
    • Minimum tractor power: 90 HP
    • PTO: 540 RPM, 4 HP (3 kW) max
    • Three-point hitch: cat 2 front and back.
    • Weight:
      • Front unit: 705 lb or 320 kg (empty), 2,645 lb or 1,202 kg (full)
      • Rear unit: 2,257 lb or 1025 kg
    • Dimensions (Figure 12):
      • Front unit: 5’7” x 4’7” x 5’7” (W x D x H)
      • Rear unit: 21’4” x 8’10” x 4’3” (W x D x H)
    Figure 12- Dimensions.

    Cost of Purchase and Operation

    At the time of writing, the purchase cost for a complete unit is around $300,000 USD, depending on the algorithms purchased and shipping fees. In the following years, there is an annual fee associated with the operating system maintenance and development. The basic subscription includes algorithms for three crops, as well as access to all beta-stage models currently in development. Additional crop algorithms can be purchased. For accurate pricing, contact their Canadian partner, Univerco.

    According to the manufacturer, the equipment does not require regular replacement of expensive components beyond standard sprayer preventative maintenance. While some components are standard and readily available, the company also keeps a regular stock of specialized parts at its warehouse in Pasco, WA, available for immediate shipping. Comprehensive service and maintenance support is provided locally by Univerco.

    Testimonial

    Wendy Zhang is the head agronomist for Keejay farms. She oversees more than 5,000 acres of diverse vegetable crops, predominantly carrot and onions. In her own words, the machine is “easy to operate, very accurate, and fast enough for a large-scale farm.” She also highlighted substantial savings on chemicals and the significant advantage of being able to safely spray close to the crop using products that cannot be broadcasted due to the risk of unacceptable crop damage.

    The most important benefit, she says, is the ability to apply treatments very close to the crop canopy, using effective rates and chemistry without compromising crop safety. No other practical tool offers this capability. A clear demonstration of its effectiveness is that no other spray equipment is currently being used for their large onion operation.

    The Grower Magazine published an excellent article about this machine, featuring other grower testimonials.

    Thanks to Olivia Soares de Camargo, Business Development Manager at Ecorobotix, for providing much of the information used in this article.

  • Circulating Spray Mix Through a Tank-Rinse Nozzle Maintains Nematode Concentration

    Circulating Spray Mix Through a Tank-Rinse Nozzle Maintains Nematode Concentration

    This article was co-written with Jennifer Llewellyn, former OMAFA Nursery Crop Specialist

    With more and more bio-rational products on the market, crop protection methods may require reassessment. Certain products require exacting water quality, cannot tolerate residues, and have half-lives that are both time- and temperature-critical. We’ve been getting questions about sprayer compatibility with some of these new products, so it seemed like a good opportunity to recycle this article from 2013.

    Many horticultural commodities, such as turfgrass and nursery crops, include the application of live nematodes as part of their annual IPM program. We performed preliminary research into the claim that a grower’s nematode applications were becoming less effective. In the course of the investigation it was discovered that the nematode concentration (i.e. dose) sampled from the spray nozzle was diminishing over the course of the application.

    (A) Tank-rinse assembly mounted through tank lid with a flow-regulating valve. (B) Close up of tank-rinse nozzle.
    (A) Tank-rinse assembly mounted through tank lid with a flow-regulating valve. (B) Close up of tank-rinse nozzle.

    After eliminating potential sinks in the sprayer’s plumbing (e.g. filters, strainers, etc.) it was hypothesized that the nematodes were adhering to the interior of the poly tank. If this was the case, the concentration would drop as the level of spray mix dropped. To test the hypothesis, we installed a tank-rinse nozzle to sparge the inner walls of the tank throughout the application and to re-suspend any stranded nematodes.

    A high capacity roller pump (Pentair series 1700C) was installed to operate the tank-rinse nozzle (Pentair Proclean Tankwash) during spraying. It was installed through a bulkhead fitting in the tank fill lid. During testing it was discovered that the tank-rinse nozzle shunted too much flow and pressure to maintain flow to the spray gun. A valve was installed behind the tank-rinse nozzle to restrict flow to the point where it gently rinsed the inner walls of the tank, restoring flow and pressure to the spray gun.

    (A) Installing a high-capacity roller pump. (B) Tank-rinse nozzle, with valve, installed through tank lid. (C) Control manifold installed to plumb the return, the tank-rinse nozzle, spray gun and boom. (D) The entire installed system.
    (A) Installing a high-capacity roller pump. (B) Tank-rinse nozzle, with valve, installed through tank lid. (C) Control manifold installed to plumb the return, the tank-rinse nozzle, spray gun and boom. (D) The entire installed system.
    (A) Nematodes, as-shipped, in a sponge. (B) Suspending nematodes for tank mixing. (C) Counting nematodes. (D) Undiluted, healthy nematodes in a stock solution via microscope ocular.
    (A) Nematodes, as-shipped, in a sponge. (B) Suspending nematodes for tank mixing.
    (C) Counting nematodes. (D) Undiluted, healthy nematodes in a stock solution via microscope ocular.

    The 200 L tank was inoculated with a stock solution containing 25 million nematodes (125 nematodes / ml). 20 L of the spray solution was sprayed into a bucket every 10 minutes, whereupon 1 L of spray solution was immediately removed and 1 ml volumes were sub-sampled for counting.

    In the first trial, nematode counts continued over a period of 2 hours and viability dropped by ~40%. It was assumed the damage was caused by prolonged circulation through the roller pump. In subsequent trials, the sampling duration reduced to 10 minutes (more realistically reflecting the time it took the grower to apply 200 L in the field). The tank was rinsed and re-inoculated for each trial. 1 ml samples were drawn from the spray gun, which operated continuously, with and without the tank rinse nozzle in operation.

    Univariate analysis confirmed data normality and a GLM procedure was conducted for analysis of variance. Results indicate that nematode concentration dropped by ~15% without tank-rinse with minimal nematode damage observed. With the tank-rinse nozzle engaged, the concentration still declined slightly, but significantly less (<5%) (see graph below).

    Nematode concentration over time for each condition.
    Nematode concentration over time for each condition.

    The results suggest that a tank-rinse system that sparges the tank walls preserves nematode concentration throughout an application and may lead to more efficacious applications.

    Horticultural Crops Ontario, Ground Covers Unlimited, Pentair (Hypro) and Nemapro are gratefully acknowledged for making this research possible.

  • Strainers (aka Filters)

    Strainers (aka Filters)

    The level of filtration required for any given spray operation depends on the materials sprayed and the nuisance factor: That is, the balance between lost productivity from plugged nozzles and the effort required to address them during rinsing.

    There are opportunities to install strainers at the tank opening (usually a basket), the suction-side of the pump, each section line, and behind the nozzles. While we’ve yet to see an operation that uses all four (speciality or field operations), the suction strainer and line strainers are required bare-minimum.

    This infographic explains how strainers are classified. Be aware that older strainers may use a different colour code (e.g. 50 mesh used to be red – now it’s blue).

    To convert these ratings to actual size exclusion, we look at the Mesh Width (mm). An 80 mesh (yellow) leaves a distance of 0.18 to 0.23 mm between the wires. We can convert Mesh Width from mm to microns by multiplying it by 1,000, giving us 180 – 230 microns.

    Each level of filtration should get progressively finer, ending with the nozzle strainers being slightly finer than the nozzle orifice. Nozzle catalogues will often advise you on which strainer is appropriate for the nozzle you are using.

    When we ask why operators don’t use nozzle strainers, the response is either “Because they plug” or “It’s one more thing to clean”. Well, if your nozzle strainers are plugging, it’s likely because you have an agitation (see here) or mixing issue (see here and here) further up the line. They can handle a lot before the spray pattern begins to suffer … but yes, you do have to clean them regularly so they can continue their good work.

    Running water through any strainer often fails to remove plugs and debris, which are a source of contamination that can wreak havoc later on. They have to be removed and physically scrubbed during rinsing. We ran a demo to show why this irritating process is still a must-do (here).

    If you use an airblast sprayer, you should use slotted (not mesh, which plug too easily) nozzle strainers. Beyond the obvious benefit of preventing plugged nozzles, the strainer shoulder plays a role in keeping the nozzle snug in the nozzle body. Without it, you may need additional gaskets to prevent leaks. Be aware that some nozzle strainer designs can plug a nozzle body. Learn more here.

    If you use a field sprayer with clean carrier water, liquid formulations and large nozzles, you may never need nozzle strainers. But, if you’re using a lot of dry formulations, if your agitation is under-powered, or if your fill water is less than pristine (we’ve seen frogs in sprayer tanks) then you might consider them… even if they are a nuisance to clean.

  • Nozzle Selection for See & Spray Select Spot Sprayers

    Nozzle Selection for See & Spray Select Spot Sprayers

    Spot sprays are becoming mainstream. As of 2024, John Deere’s See & Spray Select, their Green-on-Brown technology, is selling well in western Canada but it’s creating some confusion about how to outfit and run the system.

    Quick Overview:

    See & Spray Select is available on 120’ booms with either 15” or 20” spacing. It can be operated at up to 12 mph with conventional vertically oriented nozzles, or up to 16 mph with backwards oriented nozzles using a 40º adaptor available from John Deere. Optimal boom height is between 26” and 47”

    Operating speed for See & Spray Select is measured at the boom. That means if an operator drives at the 12 mph limit and the boom yaws forward under normal driving or in a turn, the boom speed will exceed 12 mph and it will enter “fallback” mode. Fallback mode is intended to provide weed control when camera vision is compromised due to dust, height, or speed, and typically it means that all the nozzles in the affected boom region are turned on. To avoid unnecessary waste, an operator will want to minimize fallback mode and therefore will want to drive slower than the maximum allowed boom speed.

    An operator has a choice of selecting a single-nozzle or overlapping-nozzle activation. In single nozzle mode, only the nozzle in the weed’s lane is turned on. In overlapping mode, one adjacent nozzle on each side is also turned on, for security. Overlapping mode is available on most spot spray systems to compensate for spray displacement in a side-wind, for example.

    Research at the University of Wisconsin has shown that the overlapping mode resulted in more consistent weed control in a side-wind.

    Nozzle Selection

    Overlapping mode makes nozzle selection easier because the fan angle is not as critical. Nozzles are allowed to overlap as they’re supposed to on a broadcast boom, and the spray dosage is a function of nozzle size, spacing, and travel speed. It’s also easier because boom height movement doesn’t affect the dose, so long as the required overlap remains. But nozzle fan angles should still not be too wide.

    Single nozzle activation can save more product. But in this mode, nozzle fan angle is critical because it determines the band width. Unfortunately, current nozzle selection is poor – most manufacturers aren’t offering any narrow-enough fan angle nozzles yet. For this reason, John Deere’s nozzle recommendations are intended primarily for overlapping mode.

    With single nozzle activation, the nozzle pattern (band) width needs to be fairly close to the nozzle spacing, but still have some overlap when adjacent nozzles are activated in a weed patch. The more the pattern width exceeds the nozzle spacing, the greater the underdosing in single nozzle activation compared to overlapping sprays. This conundrum is unavoidable. The closer these two values (pattern width and nozzle spacing) are to each other the better. But for this to work, boom height has to be consistent. Too low a boom creates gaps between adjacent narrow patterns. Too high and the pattern width widens, reducing the single nozzle dose. There is simply not much room for error.

    Broadcasting Background Dose

    With See & Spray Select, the A solenoid (front nozzle in ExactApply) can be used to apply a PWM broadcast spray simultaneous to the spot spray. This feature is useful with early season application because of just-emerged weeds that may be missed by the sensor. We might choose about 1/3 of the full rate applied this way, a dose which is sufficient to control these small weeds. With a tank mix for 10 gpa, one would spray 3 gpa with the front boom and 7 gpa with the B solenoid, the spot spray. This way the entire field receives the 3 gpa dose, while larger weeds that trigger the spot spray receive the 10 gpa dose.

    The problem is again with nozzle availability. For example, 3 gpa with 15” spacing at 11 mph with PWM (broadcast mode) requires a small nozzle such as an 01 (orange) or 015 (green). These are hard to find in a low-drift version. Increasing the broadcast water volume to 5 gpa would allow an 02 (yellow) nozzle to be used. A 20” spacing would allow even larger nozzles to be used, for 3 gpa an 025 (lilac) is a possibility and this greatly improves the available choice. At 5 gpa, an 03 size is suitable, and now the John Deere LDM nozzle is an option (it is not manufactured in sizes smaller than 03).

    Let’s assume a user selects 5 gpa for the broadcast based on nozzle availability. The next decision is whether to adjust the total applied volume upwards. If sticking with a 10 gpa tank mix, the spot spray would also be 5 gpa, making the broadcast 50% of the dose.  

    Alternatively, one could increase the spot spray volume to 10 gpa, mixing the tank for 15 gpa. This returns one to 1/3 of the total dose as broadcast, and 2/3 as a spot spray.  A reason for doing this is to make nozzle size selection easier and also improving the product savings of the system.

    The spot spray from the B solenoid is not PWM, which allows for a more straightforward nozzle sizing, as well as the use of air-induced tips which are available in a large number of sizes.

    A summary of some possible nozzle combinations for two nozzle spacings and travel speeds is listed in Table 1.

    Table 1: Possible nozzle sizes for overlapping mode in John Deere See & Spray Select Note that the travel speed is lower than the maximum allowed, to accommodate boom yaw.

    If the operator chooses single nozzle activation, the fan angle of the nozzle becomes important. To recap, one would want to have a nozzle that can do two things:

    1. Cover a band that is close to the same width as the nozzle spacing when a single weed activates a single nozzle, and
    2. Provide sufficient overlap when multiple adjacent nozzles are activated in a larger weed patch.

    It’s not possible to have a band width as narrow as the nozzle spacing and still get an overlapping pattern when it’s needed. This means the dose for a single nozzle pattern will unavoidably be spread out wider, resulting in a lower dose for any weed it encounters compared to the overlapping activation. But the wider the fan angle, the wider the band and the lower the dose, resulting in possibly reduced control for single nozzle activations.

    On the other hand, a narrower band limits the boom height at which an acceptable overlap can be achieved. Let’s say an overlapping nozzle needs to have 30% overlap to get an acceptable spray distribution. At a 20” spacing, the band would need to be 26” wide (a 24% under-dose on a single nozzle compared to an overlapping section).  Band width will change with boom height, but it depends on the fan angle. For a 60 degree fan angle, the band changes by about one inch for every inch of boom height. That means even with a modest 10” vertical movement of the boom, the dosage might change by 30%, a fair amount.

    Actual changes depend on the nozzle spacing and the fan angle, but the point remains that this is a significant dosage change that could affect weed control. And this change in dose is because of boom sway.

    Recommendations

    What should a spot spray user do?  One thing is clear, compromises will be necessary.

    The most consistent application will be achieved with overlapping mode, but at the cost of forfeited savings. These lost savings may be recovered due to fewer weed control failures, or less need to re-spray.

    On the other hand, the greatest savings will be achieved with single nozzle activation. But fan angle will need to be carefully selected and boom height consistency will be critical.

    Availability of narrow fan angles is limited. Only Wilger (20, 40, and 60 degree DX), Greenleaf (40 degree Spot Fan), Arag (CFLD-CX 40 degree) and Magnojet (30 and 60 degree) offer spot spray-specific low-drift nozzles off the shelf. TeeJet has issued DriftGuard (DG) versions of 65 degree nozzles for the Australian spot spray market, with the DG65055 a special nozzle that conforms to the VC spray quality requirement needed for 2,4-D products.

    John Deere has recently (Spring 2025) released an 80 degree spot spray tip called the TSL. It ships with the angled adaptor for faster spray speed. However, 80 degrees is still not narow enough to permit single nozzle activation without some significant rate compromises between single and overlapping mode.

    The availability will need to increase, not only in terms of fan angles, but also in flow rates and spray qualities. With spot sprays remaining a relatively small market this will take time. But the success of spot sprays also depends on it.

    One question that only experience will answer is the relative frequency of single vs multiple nozzle activation for any given farm. If the majority of the activations are multiple nozzles, then setting up the nozzles for that situation (i.e., opting for wider fan angles that create more overlap) makes most sense.

    But regardless of the choice made by the user, the need for stable booms remains paramount. This feature will be the basis on which any progress in spot spray adoption will be built.  Call your dealer. Tell them how important boom stability is.

  • Sprayer Cleanout and Cleaner Selection

    Sprayer Cleanout and Cleaner Selection

    Editor’s Note: Changes have been made to this article since its original publication in 2015.

    When in-crop spraying is around the corner, sprayer tank clean out is an important topic to address on your farm. Many farms have done the same clean-out routine for years and not had any issues with contaminating residues in the tank resulting in crop damage. Although the old saying “If it ain’t broke, don’t fix it” definitely has some merit, in this case it is good to question whether your cleanout routine is adequate. When you consider the way chemicals have changed over the years, especially the higher reliance on oily surfactants in modern chemicals, it makes sense why we need to pay attention to spray tank cleanout.

    The goal of cleaning the tank is to remove and dilute the previous chemical formulation as much as possible to prevent buildup and carryover of residues which can cause crop damage on non-target crops.

    Safety First

    Always wear safety gear before working around chemicals. Although it can be a hassle, we all know that it is no fun spilling chemical on your clothes and skin. What’s even worse is smelling it all day in the sprayer cab. I use a long waterproof coat, a plastic face shield to prevent back splash when spiking jugs, and of course rubber gloves (No judgment on me looking like a total dork please:).

    Safety First - Are you looking at my headgear? Are you!?
    Safety First – Are you looking at my headgear? Are you!?

    1 – Get the Previous Product Out of the Tank ASAP

    In my experiences spraying, I have always tried to get the previous product out of the tank as soon as possible. Spraying the extra product out of the tank is the safest and most environmentally responsible way to rid your tank of left over product. Dr. Tom Wolf of AgriMetrix Research and Training, states that spraying a crop twice is usually safe, as all herbicides must be registered to be sprayed at twice the rate in order to be registered by the Pest Management Regulatory Agency (PMRA). If one lets the product sit in the tank overnight before beginning the cleanout, there is more time for product to congeal and adhere to the tank and plumbing components.

    Ball valve on main filters.
    Ball valve on main filters.

    I open the valve ends on my filters to empty the buildup in the bottom of the filter canister. There is often chemical residue or green slime from dug-out water in here. Next I like to go along my booms and empty out all the chemical product within the boom plumbing. Our farm runs a Patriot 4420 sprayer, with valves on each boom section to empty out product. Usually I will go to the sprayer and tip the boom ends up so that gravity allows all of the product to drain out. Then I raise the centre rack, and tip end of booms down to force the product to drain out the other way. You would be amazed at how much product comes out by doing this both directions!

    Valves on each nozzle.
    Valves on each nozzle.
    Tipping the boom ends up with the centre rack down.
    Tipping the boom ends up with the centre rack down.

    While the tank is empty and no pump is running, I will remove all the filters on the sprayer, and grab the handy dandy toothbrush – this is the most valuable tool in filter cleanout! This brush is just small enough to get it in the centre of the filter and scrub all of the residue and gunk out of the filters. A pail filled with rinsing solution is an easy way to clean filters and nozzles.

    Possibly the most important cleaning tool. Don't put it back in the bathroom afterwards.
    Possibly the most important cleaning tool. Don’t put it back in the bathroom afterwards.

    2 – Begin Rinsing Process

    I used to always put about 1,000 gallons of water to our 1,200 gallon tank, thinking that a larger volume would clean all areas of the tank better, but I’ve since changed my thinking. Research has shown that two or three smaller rinses *aka triple rinsing) is more effective for rinsing the tank than one large volume rinse. I always crank the agitation up to high and allow the cleaning solution to agitate for as long as possible.

    Nowadays I try to do three 400 gallon rinses.

    1st RinseCleaning product plus 400 gallons water
    2nd RinseCleaning product plus 400 gallons water
    3rd Rinse400 gallons of just water to rinse, and run through plumbing system to check nozzles and for leaks

    Many labels Recommend leaving the rinsing solution in the tank and lines overnight. This will allow more chemical deposits to loosen up. If an operator is forced to speed up the tank cleaning process due to limited time, they must understand that there are risks involved in doing a less thorough tank cleaning.

    Cleaning Products

    Detergent or ammonia? Check the label. If the label doesn’t specify, you can consult this table from Winfield United.

    Detergent CleanerAmmonia
    Solution contains an adjuvantSulfonylureas (SU’s)
    Solution contains a milky looking component (an Emulsion or EC)Thiencarbazone – methyl
    GlufonsinateFlucarbazone
    Imi’s (Group 2)Dicamba
    Simplicity

    Detergent (e.g. All Clear)

    This detergent cleaner is specifically designed to remove pesticide deposits and other debris, including oily substances from booms, filters, and nozzles. Use All Clear (or other detergent cleaner) if the solution is milky-looking (called an emulsion), which means it is oil-based.

    • Label rate is 0.25 L of All Clear/100 L of water.
    • If you are adding 400 gal of water, you will only need 3.78 L of cleaning product.
    • Decontamination rate is double this: 7.57 L of cleaning product. Use this rate if you have had residue issues, or to do a more thorough cleaning.

    pH Increaser (aka Ammonia; e.g. Flush)

    This is an ammonia based cleaning solution. This product is used to raise the pH to increase solubility of most Group 2 products (from FMC, Bayer, and Corteva but not BASF). Flush contains 7% ammonia. Use Flush (or other ammonia based cleaner) for most cleaning, but especially for Group 2 products listed above, such as Varro, and Velocity M3, Express, Refine, Muster, and Spectrum.

    • Label Rate is 0.50 L of Flush/100 L of water.
    • If you are adding 400 gal of water, you will need exactly 7.57 L of cleaning solution.
    A pail and detergent are "must-haves" during sprayer cleanup.
    A pail and detergent are “must-haves” during sprayer cleanup.

    Combo Products

    Alternately, some solutions raise pH without ammonia. FS Rinseout is sodium hydroxide based, not ammonia based. It is a high alkaline solution that elevates and holds the pH combined with strong surfactants to help clean the tank. Another is CleanOut, which uses potassium hydroxide and disodium metasilicate, a detergent. In both cases they are both pH increases and detergents.

    3 – Draining the Rinse Solution

    After I have ensured all nozzles are working correctly, and there are no leaks in the system, I drain out all of the rinse water, fold in the booms, and get ready to fill the tank with chemical solution for spraying!

    More Information

    Learn where residue can hide. This video was filmed for the Environmental Farm Plan with the nice people at Clean Field Services in Drayton, Ontario. Hardly the height of our acting careers, but good messaging nonetheless.