Spraying
Blackleg is caused by two species of the pathogen. The major one is called Leptosphaeria maculans. The other one is a much less virulent species called Leptosphaeria biglobosa. For control of the disease, pathologists look at some of the weak links where we can apply most of the impact on the disease. The pathogen only survives on residues. If you don’t have a residue, it doesn’t survive well in the soil. That’s why rotation is important.

The pathogen produces a fruiting body in the spring called a pseudothecium or another type called a pycnidium. They produce spores that land on the cotyledons of canola. If you have insect damage from pests like flea beetles, the infection can be worse. With wounding, the pathogen can get into the cotyledon tissue even without moisture. From there the infection develops and you see the cankers at the base of the stem later on in the growing season.
Slide 4
Photo courtesy of Gary Peng.

There are three important things that can lead to an infection:
·      there’s residue to harbour the pathogen inoculum
·      you need to have early infection to get into the stem
·      insect damage may help the infection to occur more severely. 

The disease was very prevalent in the late ’80s, early ’90s. Then we introduced some resistant varieties in the early ’90s, which brought down the occurrence for many years. Partially that was resistance bred into varieties, but we also had three- or four-year rotations. That was a big part of the whole management effectiveness.

In the last five to six years, the disease incidence has been creeping back up to 20 to 25 per cent in Alberta and Manitoba, and about 10 per cent in Saskatchewan. However, the average severity remained below level 1 (light). Research by Sheau-Fang Hwang in Alberta indicates that in most years, this level of severity could result in a yield loss of about two to eight per cent on a susceptible variety. But from a trade perspective, our trading partners want to see the disease level trend going down.

Why the upward trend?
The first reason for an increase in blackleg incidence is likely the change of the pathogen population, which is adapting to the resistant varieties. The pathogen population may be becoming more virulent or with a greater proportion of virulent isolates in it. 

Plant breeders have used major gene resistance to control the disease. The resistant gene blocks the infection by the pathogen carrying the corresponding avirulence gene. For example, an Rlm3 resistant gene would block the pathogen with avirulence AvrLm3 gene (abbreviated to Av3). It might be like a lock-and-key, but for some reason, over time, the Av gene may change and the resistant gene may not be able to recognize it.

My colleague, Randy Kutcher, looked at the change in pathogen populations in 2007 when he looked at the avirulent gene prevalence on the Prairies. In his work looking at 800 isolates of L. maculans, the percentage of Av2 and Av6 genes were very high in the population, and the others at more moderate to low levels. Further work in 2010 and 2011 with Dilantha Fernando at the University of Manitoba found the picture had changed quite a bit. The presence of the Av3 and Av9 genes had decreased quite a bit, but at the same time Av7 seemed to be increasing quite a bit. That means the Rlm3 gene would be less likely to be effective across the Prairies because the Av3 gene had changed mostly to the virulent type. The Rlm3 gene was first introduced back in early 1990s and has been used for over 20 years.

Other research in Fernando’s lab also looked at what resistant genes are present in 206 varieties/breeding lines in Western Canada. The resistance gene that was predominantly found was Rlm3 in around 70 per cent of the varieties/breeding lines. There was also a bit of Rlm1 detected as well. Overall, the diversity of R genes is still quite limited in the germplasm tested. The important message is that Rlm3 is not going to remain effective on the Prairies because the corresponding Av3 gene is already fairly low in the pathogen population. 

However, when we looked at field data in Alberta and Manitoba, while the occurrence of other Av genes was high, disease levels ranged widely. This told us there was something else going on, which we called non-specific resistance in our varieties, although the effect was definitely less than the major gene resistance.

We further investigated this non-specific resistance in our varieties. We tested commercial varieties with a pathogen without a corresponding Av gene so any resistance observed would be due to non-specific gene resistance. Almost all the varieties had a slightly smaller amount of the disease on inoculated cotyledons than the susceptible Westar. At the same time, it’s a totally different kind of resistance reaction as opposed to the major gene resistance. It would not stop the infection completely – it just slowed it down a little bit, and on some varieties, substantially.

A further look at three of those varieties found the progress of plant mortality originated from cotyledon or petiole inoculation was somehow reduced, but varied between the varieties. Using a fluorescent protein gene labeled isolate, photography was able to show the reduced spread of the pathogen in the cotyledon compared to the susceptible Westar variety.

If you can slow down the movement from the cotyledon via the petiole into the stem, there may not be enough of the pathogen getting into the stem before the cotyledons drop off. This is one of the reasons that non-race-specific resistance works in some of those varieties we have.
SLIDE 22
Photo courtesy of Gary Peng.
Click here for part two: management strategies

This article is a summary of the presentation “Managing blackleg of canola in Western Canada,” delivered by Dr. Gary Peng, Agriculture and Agri-Food Canada, Saskatoon, at the Field Crop Disease Summit, Feb. 21-22, 2017. Click here to download the full presentation.

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Published in Diseases
Scientists with the University of Tennessee Institute of Agriculture have found that the overall health of honeybee hives actually improves in the presence of agricultural production.

The study, “Agricultural Landscape and Pesticide Effects on Honey Bee Biological Traits,” which was published in a recent issue of the Journal of Economic Entomology, evaluated the impacts of row-crop agriculture, including the traditional use of pesticides, on honeybee health. Results indicated that hive health was positively correlated to the presence of agriculture. According to the study, colonies in a non-agricultural area struggled to find adequate food resources and produced fewer offspring.

“We’re not saying that pesticides are not a factor in honeybee health. There were a few events during the season where insecticide applications caused the death of some foraging bees,” says Mohamed Alburaki, lead author and post-doctoral fellow with the University of Tennessee Department of Entomology and Plant Pathology (EPP). “However, our study suggests that the benefits of better nutrition sources and nectar yields found in agricultural areas outweigh the risks of exposure to agricultural pesticides.”

A​ccording to the study, hives located in areas with high to moderate agricultural vegetation grew faster and larger than those in low or non-agricultural areas. Researchers suggest the greater population sizes enabled better colony thermoregulation in these hives, as well.

Meanwhile, bees located in a non-agricultural environment were challenged to find food. Although fewer pesticide contaminants were reported in these areas, the landscape did not provide sustainable forage. In fact, during the observations, two colonies in the non-agricultural areas collapsed due to starvation.

Disruptions and fluctuations in brood rearing were also more notable in a non-agricultural environment. Interestingly, brood production was highest in the location that exhibited a more evenly distributed mix of agricultural production, forests and urban activity.

“One possible explanation for this finding could be the elevated urban activity in this location,” says Alburaki. “Ornamental plantings around homes or businesses, or backyard gardens are examples of urban activity that increase the diversity of pollen in an area. Greater pollen diversity has been credited with enhancing colony development.”

Researchers also evaluated trapped pollen from each colony for pesticide residues. Low concentrations of fungicides, herbicides and insecticides were identified, but at levels well below the lethal dose for honey bees. Imidacloprid was the only neonicotinoid detected, also at sub-lethal levels.

Agricultural pesticides, particularly neonicotinoids, are considered by some to be a key factor in declining honeybee populations. The UTIA study found that higher exposure to pesticides in agricultural environments did not result in measurable impacts on colony productivity.

This study was supported in part by the U.S. Department of Agriculture’s Agricultural Research Service Pest Management Program.
Published in Corporate News
Surveys of sunflower rust in Manitoba show variations in the predominance of different races from year to year, but the overall trend is towards races with greater virulence.
Published in Diseases
Set out a free smorgasbord and see who shows up. In the case of fababean, as acreage has risen, pea leaf weevil and lygus bug have been coming to dinner. For producers, the main concern with pea leaf weevil is feeding on nitrogen-fixing nodules, while for lygus bug, the economic impact is related to seed quality.
Published in Insect Pests
In wheat, in canola or in pea, the message is the same: control weeds early for highest yields. Those messages have been repeated in the past and now new research highlights the need to repeat that same message with respect to wheat crops.
Published in Weeds
When farmers spray their fields with pesticides or other treatments, only two per cent of the spray sticks to the plants. A significant portion of it typically bounces right off the plants, lands on the ground, and becomes part of the runoff that flows to streams and rivers, often causing serious pollution. But a team of MIT researchers aims to fix that.

By using a clever combination of two inexpensive additives to the spray, the researchers found they can drastically cut down on the amount of liquid that bounces off. The findings appear in the journal Nature Communications, in a paper by associate professor of mechanical engineering Kripa Varanasi, graduate student Maher Damak, research scientist Seyed Reza Mahmoudi, and former postdoc Md Nasim Hyder.

Previous attempts to reduce this droplet bounce rate have relied on additives such as surfactants, soaplike chemicals that reduce the surface tension of the droplets and cause them to spread more. But tests have shown that this provides only a small improvement; the speedy droplets bounce off while the surface tension is still changing, and the surfactants cause the spray to form smaller droplets that are more easily blown away. | READ MORE
Published in Corporate News
Full registration of the imidazolinone-tolerant (IMI-tolerant) chickpea system with recommended chickpea varieties and registered Solo herbicide is imminent. Two IMI-tolerant chickpea varieties – CDC Alma (Kabuli-type) and CDC Cory (Desi-type) – have already been developed. The Prairie Pesticide Minor Use Consortium has submitted the application for Solo herbicide use on IMI-tolerant chickpea to the Pesticide Management Regulatory Agency (PMRA) and registration could be received in early 2017.  
Published in Pulses
Our enemy’s enemy is our friend. That’s the idea behind a calculator being developed to help Prairie cereal growers make decisions on whether to apply insecticides. In this case, our enemies are the various aphid species that infest cereal crops. If aphid populations are high during a sensitive crop stage, these delicate little insects can make a big dent in cereal yields. The aphids’ enemies include an array of insects that are able to chomp down, suck dry or otherwise destroy impressive numbers of aphids.
Published in Insect Pests

June 15, 2016 - Salford Group unveiled what it says is the largest pull-type pneumatic boom applicator on the planet. The whopping prototype is being shown for the first time in public at Canada's Farm Progress Show this week in Regina.

Published in Sprayers

Mar. 16, 2016 - According to the Canadian Agricultural Injury Reporting (CAIR) program, 13 per cent of farm-related fatalities across Canada are traffic-related, and most involved tractors.

During the busy spring season, farmers often travel long distances between fields, and this requires transporting equipment on public roads throughout rural Alberta. Farm equipment is oversized and slow compared to other vehicles using the roads and when certain procedures are not met, this can lead to collisions and other incidents.

"Maintenance is a contributing factor to the safety of transporting farm equipment," says Kenda Lubeck, farm safety coordinator, Alberta Agriculture and Forestry (AF). "Poor maintenance of equipment such as brakes or tires can lead to loss of control of the vehicle."

Check all tires for air pressure, cuts, bumps and tread wear. Always lock brake pedals together for highway travel as sudden braking at high speeds on only one wheel could put the tractor into a dangerous skid. Equip heavy wagons with their own independent brakes.

The number one cause of farm-related fatalities in Canada is machinery roll overs. To minimize the risk of severe injury or death to the operator, all tractors need roll-over protective structures (ROPS)," says Lubeck. "In addition, operators should always wear a seatbelt as ROPS are ineffective in a roll over without this restraining device."

To avoid traffic collisions between motorists and farm equipment, farmers should ensure their equipment is clearly visible and follows all regulated requirements for lighting and signage. This will ensure approaching traffic has time to react to a slow-moving vehicle. Use reflective tape and reflectors in the event that large equipment is required to travel in dim lighting conditions. In Canada, reflective material should be red and orange strips. You can purchase tape in kits or by the foot at local farm or hardware stores.

Dust-covered signage and lights make farm machinery less visible to motorists and dust-covered machinery causes poor visibility for the operator, who may not see oncoming traffic. Be sure to clean farm equipment prior to transportation to minimize the risk of collision due to poor visibility.

"It's important to note that regulated requirements for lighting and signage on public roadways include the use of a slow-moving vehicle (SMV) sign," explains Lubeck. "The SMV sign must be properly mounted, clean and not faded. It must be positioned on the rear of the tractor or towed implement and clearly visible. SMV signs must only be used on equipment travelling less than 40 km/hr."

For more information on the safe transportation of farm equipment on public roads, see AF's Make it Safe, Make it Visible or go to www.agriculture.alberta.ca for more information on farm safety.

 

Published in Maintenance

Mar. 31, 2016 - Much of the tracks-versus-wheels debate on farms has focused on compaction and the ability to drive in wet conditions, but what about differences in fuel consumption?

Testing done in southern Manitoba in 2015 confirmed long-standing research showing tracks require less energy to move in field conditions, dispelling a lingering misconception that implements on tracks require more horsepower to pull than wheeled units.

Research conducted near Altona — the home of track-maker Elmer's Manufacturing — found fuel savings of 11 to 15 percent when pulling a grain cart on tracks instead of wheels.

"We used a grain cart and compared wheels to tracks at the same weights. We tested on fresh tilled ground, tilled and then dried for a few days, untilled canola ground, and concrete for a reference." explains Mike Friesen, general manager and lead engineer at Elmer's.

While wheels pulled easier than tracks on concrete, there was less resistance pulling tracks in all three field scenarios.

That's because tracks "float" or stay higher on top of the soil, reducing what engineers describe as "rolling resistance." Since tires generally create deeper ruts, they have a greater rolling resistance than tracks on soft soil, as explained by researchers AJ Koolen and H Kuipers in Agricultural Soil Mechanics back in 1983.

"In plain English, the tracks don't have to continuously try to get out of the rut they are digging like the wheel does," explains Friesen.

Hartney, Manitoba farmer Tim Morden's experience pulling large capacity Bourgault cart on Elmer's TransferTracks supports the findings.

"When we had duals on the back of the cart, dirt would build up in front of the wheels and slow it down, making it hard to pull," he says. "This didn't happen with tracks."

Morden explains the biggest difference he's noticed with switching to tracks is the reduced compaction and rutting, especially in wet conditions.

"The number one fact is it doesn't really leave a rut at any time, unless it's really wet, but it's significantly less than tires," he says. "We have much more confidence on the field with the track."

The study also compared energy required to pull Elmer's large tracks versus Elmer's smaller TransferTracks, which concluded that, while both tracks pulled easier than wheels, the TransferTracks required less horsepower at weights below 35,000 lbs per wheel making it the ideal candidate for use with an air-seeder cart, small grain cart or a rolling water/fertilizer tank.

The reduced energy requirement not only results in improved fuel efficiency, but it could also allow a grower to optimize their existing horsepower in other ways, such as driving faster or pulling a wider drill with the same tractor during seeding.

 

Published in Tractors

With foliar fungicide applications, timing is a key factor in soybean yield response. A soybean specialist gives his take on the best timing options.

Based on his research results so far, “the long and the short of it is that fungicide timing is highly dependent on the year and what disease you are going after,” says Horst Bohner, provincial soybean specialist with the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA).

Bohner’s research interest in fungicide applications began about 10 years ago. “In 2004, soybean rust was found in Ontario for the first time. It was just on one leaf so it wasn’t an economic issue. But it did stir the industry to register fungicides to help control that disease if an outbreak occurred,” he explains. “Prior to that we really only used foliar fungicides in soybeans very sparingly and mostly for white mould. Unfortunately fungicides didn’t really work well for white mould control because soybeans flower for such a long time.” (For white mould, the aim of a fungicide application is to protect the flowers because infected petals are the main way the disease starts in the plant.)

“So in 2005, we started a number of trials – as did many people – to assess the different foliar fungicides available at that time. We found that there was a real yield benefit even in the absence of soybean rust; often there are other minor diseases present or, in some cases, there are no visible disease symptoms at all.”

Once they knew there was a definite yield benefit from a foliar fungicide, the next question to answer was timing-related: which soybean growth stage would be the best time for spraying? Given that soybeans flower for a long time, what timing would be the most effective for white mould? And what timing would be best for controlling other foliar soybean diseases?

Fungicide companies had been recommending that foliar fungicides be applied between the R3 (beginning pod) stage and the R4 (full pod) stage, based on research conducted mainly in the United States. However, results in some initial Ontario trials by BASF and by David Hooker from the University of Guelph’s Ridgetown campus indicated that an earlier timing, between the R2 (full flower) stage and the R3 stage, provided a greater yield benefit. So Hooker conducted trials in 2013 and found that an R2 to R3 timing increased soybean yields by about one to 1.5 bushels per acre compared to the R3 to R4 timing.

Generally in Ontario soybean trials, the yield response to a single foliar fungicide application averages about two bushels per acre, so the possibility of an extra bushel per acre is exciting. As a result, Hooker continued his fungicide timing trials in 2014 and 2015.

Hooker’s 2013 results sparked Bohner’s interest in fungicide timing. So Bohner has been conducting field-scale, replicated
trials to compare various application timings for the past two years, with funding assistance through the Grain Farmers of Ontario.

Bohner’s 2014 trials involved Priaxor and Acapela, and took place at Bornholm, Lucan and St. Thomas, with two soybean varieties at each site. The fungicide timings were: untreated control; in-furrow; V6; R2; R4; in-furrow + R2; and in-furrow + R2 + R4.

The 2015 trials involved Priaxor, Stratego Pro, Allegro and Acapela, and were conducted at Bornholm and Lucan, with two soybean varieties at each site. The timings were: untreated control; in-furrow; V6; R2; R4; and R2 + R3.

The in-furrow treatment was included in the trials because interest in liquid in-furrow applications in soybeans has been increasing in Ontario. “The idea of applying a foliar fungicide in-furrow is to help protect the roots and early seedlings, similar to putting a fungicide on the seed, which is what we often do now; most certified soybean seed has a fungicide on it,” Bohner explains. He notes that in-furrow foliar fungicide applications are being tried in the United States with mixed results.

The tables on the right show the yield results of the different treatments in 2014 and 2015. So far in the trials, the in-furrow and V6 fungicide timings have not resulted in statistically significant yield gains.

In 2014, the wet, cool weather conditions favoured white mould at two of the sites. The results showed that if white mould is present at moderate levels, then using a foliar fungicide can produce large yield gains. The greatest yield benefit occurred with the most intensive treatment (in-furrow + R2 + R4); the in-furrow portion of this intensive treatment likely did not affect the yield.

In 2015, there was no statistically significant difference between any of the yields, likely because there was no disease pressure present.

Timing tips
Bohner’s results show that the choice between R1, R2, R3 and R4 timing depends on which disease is the major concern and on the weather conditions.

“If you are trying to suppress white mould – white mould is a really hard disease to control so we talk about suppression – you need to think about spraying two times in the growing season. Because you are trying to protect the flowers, consider spraying at R1 [first flower] and then following up with another application 10 to 14 days later, which is around R3. The timing of the first application is not the early part of R1, because R1 can happen quite early in the season. Often R2 is fine for the first spray; if you do that, then you would follow with another application at R4,” Bohner says.

“[The choice between a late R1 timing and an R2 timing] depends on the growing season, how big the plants are, how much moisture there is and how much it looks like there is going to be a disease problem. One of the main considerations is coverage. If the plants are quite small and good coverage can be achieved at R2, then this timing is likely all right.

 “For the other foliar diseases, when most growers will only need to spray once, the earliest you should spray is at R2,” he adds. “In 2015, we showed that you could spray right up to the R4 stage and get the same [yield] response as at the R2 stage. So the window for the correct timing is wider than we thought it was. It probably ranges from mid-R2 to R4 in most years, depending on the growing conditions that season.”

With these other foliar diseases, you have some time to scout and decide whether the disease problem is serious enough to warrant a fungicide application. For white mould, however, you cannot wait until the disease shows up in the crop. “Typically at that late R1, R2 or R3 stage, when you’ll be spraying the first time for white mould, almost no disease would be present. So you have to base your spray decision on the field’s disease history and the weather. If it is cool and wet, and you have had a lot of disease in that field, in my estimate you should apply that first spray at the late R1 to early R2 stage. And then you see what the weather does. If it is wet and cool and you are starting to see some white mould, then you spray again 14 days later. If it turns hot and dry, you don’t spray again,” Bohner explains.

He emphasizes, “If you wait to see significant white mould in the crop, then it’s too late to spray. The research shows that. If you wait to spray at R5, for instance, there is no response at all to a fungicide. The disease is set in.

“Overall, if you are going to chase control of disease and higher yields with these fungicides, then so far in my work, two applications provide much more consistent results. Of course the problem with that is the cost. And the cost is a pretty big barrier.”

foliargunicidetablesfeb16

 

 

 

Published in Soybeans

 

Spraying herbicides well is both an art and a science. But it’s also mostly a matter of always doing certain things and never doing others, according to Mike Cowbrough, weed management field crops lead at the Ontario Ministry of Agriculture, Food and Rural Affairs  (OMAFRA), and Steven Johns, agronomic sales rep with Syngenta Canada.

So how do farmers improve weed control success through spraying well? Let’s first look at mixing. Cowbrough points out that successful tank mix compatibility is all about starting with a clean tank and making sure products are mixed efficiently. “Some products are easy to foam, like glyphosate and water, and if you add a de-foaming agent prior to adding the glyphosate, that will take care of it,” he says. “Also, always make sure your inductor is full so it’s not drawing air, and minimize agitation.”

More serious issues with gelling and clogging of spray lines seem to occur often with EC herbicides and a dry granular product. “Do a jar test if there is any doubt,” advises Cowbrough. “Mix up a little batch in a pint jar that’s the equivalent measurement to what you’d apply to an acre. I once mixed 2,4-D amine and Sencor DF, for example, in a jar test and didn’t let Sencor dissolve well enough first, so I got a coarse white precipitate in the jar that was hard to flush away. It would be exponentially worse to clean up in a sprayer.”

Johns advises those using a new tank mix to ask the retailer to double-check about things like mixing order. “Surfactants can also be added to make products compatible,” he says. “Many products that contain atrazine don’t ‘like’ to be mixed with glyphosate, but if you add a non-ionic surfactant, you can make them very compatible.” He reminds farmers to pay attention to the general
mixing rules: add wettables, powders, granules, then agitate, then liquids, flowables, and ECs, followed by true solutions.

“All of us are in a hurry at springtime, and we have to slow down and remember that these products were never designed to mix with each other, so we need to mix one thing at a time, and give it time,” he notes. “With dry flowables, put them through the inductor to smash them and then they’ll get suspended well in solution. Temperature and water volume are also very important.”

Cowbrough agrees. He notes that low water volumes can have a very negative influence on how well high-volume dry granular flowable herbicides dissolve. He advises using high water volumes if you want to have complete dissolving, and prevent product sedimentation in the first place. “With any flowables or wettables, you should have valves on your boom sections, and flush your system well,” Johns adds. “I’d also like to stress that you should never leave a partial tank sitting around unapplied, unless you have the spare time to agitate it every hour or two until you want to finish applying it. If you let stuff sit in sprayers for any length of time, sedimentation can occur. So, go ahead and finish spraying even if it’s raining. And also remember, never put products into jugs that aren’t correctly labelled.”

Cowbrough also makes the point that products might not fully dissolve in acidic or alkaline water. He says studies done at Purdue University in the U.S. showed that the efficacy of Eragon was found to be reduced in acidic water, for example. “The price of litmus paper is cheap, so testing your water is worth it,” he notes.

Application advice
Last year, Cowbrough and his colleagues conducted weed surveys across the province in six counties and found that six weed species were predominant. Canada fleabane and giant ragweed are at the top of the list, but so is lamb’s-quarters. “It’s a species that we get asked about in terms of whether it’s herbicide-resistant,” he notes. “But that’s not going on and yet it seems to be resistant. So, what is it?”

Johns notes that to answer that, we need to take a close look at application. “Soil application is different than contact post-emergence application, but with lamb’s-quarters or giant ragweed, we advise using a higher water volume post-emergence,” he says. “You are spending a lot of money on herbicides, so make sure they work. Don’t skimp and you’ll get much better droplet dispersion and much better results.”

Cowbrough’s survey results also revealed the fact that what is being reported as lamb’s-quarters might actually be fig-leaved goosefoot. “So, make sure to do good scouting,” Cowbrough advises. “And make sure you are trying to spray when the lamb’s-quarters are small, at the eight-leaf stage. When you apply herbicides at this stage, control is excellent.” At medium size (three to four inches tall), glyphosate efficacy with lamb’s-quarters is still excellent, but the efficacy of Basagran and Pinnacle falls off. At six to eight inches tall, Basagran and Pinnacle are not effective on lamb’s-quarters at all, Cowbrough notes, and glyphosate cannot do well because there is too much calcium in the leaves. He adds that if weeds are at a high density, they can shade and protect each other; so again, getting them when they are small is very important.

So, size matters, but so does time of day. Cowbrough says different time-of-day herbicide applications on velvetleaf and lamb’s-quarters were recently compared by Peter Sikkema, a crop scientist at the University of Guelph (Ridgetown). Sikkema found that control of velvetleaf is much better if spraying is conducted between 9 a.m. and 6 p.m. Johns points out that earlier than 9 a.m. and later than 6 p.m., dew can interfere with efficacy, so make sure the field is dry. Time of day also affects leaf orientation. For velvetleaf in particular, the leaves drop as the sun goes down, so spraying later in the evening is not recommended. The efficacy of glyphosate and other herbicides can also be reduced by soil and dust on weed surfaces.

“Also keep in mind that a thick crop canopy appears to serve the same function of another residual herbicide application,” Cowbrough notes. “Less sunlight getting through means fewer weed seeds germinate. So, use whatever seeding rates and whatever row space you wish, but don’t ignore fertility.” He says studies have shown that soybean canopy closure is much quicker with the use of both a pre- and post-emergent herbicide program. “But we know that less than 20 per cent of glyphosate-tolerant soybeans receive a pre-emergent herbicide application,” he says. “That’s something to think about.” 

 

Published in Weeds

July 7, 2015, Salford, ON - Salford Group continues to broaden its fertilizer application line with the addition of several new products that come as a result of its recent acquisition of both BBI Spreaders and Valmar Airflo. The global agriculture equipment manufacturer has added two new spreaders and the largest pull-type pneumatic boom applicators on the market to its product offering.

New to the Canadian market are two Salford BBI spreaders, the MagnaSpread Ultra and Javelin. This equipment has previously been distributed through farm equipment dealers in the American market but with increased distribution through the Salford network, the company is now excited to offer this equipment throughout Canada as well. Both featured in the Producer Series, these spreaders are optimized for large-acreage operations, a hallmark of the western Canadian market.

The MagnaSpread Ultra is a massive fertilizer and lime spreader, capable of carrying over 500 cubic feet of product with optional bin extensions. This huge capacity allows the Ultra to cover more acres between fills. To stand up to roughly 14 tons of material while minimizing compaction, the Ultra is equipped with 710/50 R 30.5 tires and a proprietary 20-ton BBI walking beam suspension.

An exclusive continuous duty hydraulic system maintains a 90 percent efficiency rate, against the former industry standard of 70. This system gives the MagnaSpread Ultra hydraulic power to spare, running at 1.5 times the former standard in the large-scale fertilizer/lime spreader class, supercharged with 60 percent more horsepower and 50 percent more torque.

The Javelin, a mid-season, top-dress fertilizer spreader, was the first in North America to broadcast dry material in 120-foot swaths (Urea). This means less time in the field and less soil compaction for large-acreage applications. With greater efficiency overall, the Javelin saves time and fuel costs and brings greater yield potential to farmers.

Both spreaders arrive in the field standard equipped with the Task Command System from Salford BBI Electronics but are compatible with other precision farming equipment as well. The Task Command System offers producers true precision farming technology, with guidance and variable rate control among its capabilities.

Salford also welcomes the Salford Valmar 8600 to its product line. Valmar manufactures the only pull-type pneumatic boom fertilizer applicators on the market, with the 8600 being the largest model.

The 8600 gives farmers increased versatility through its 54, 57, 60 and 66 ft. boom widths, standard half-machine shut off, and its option package for metering and tire types.

What sets Salford Valmar applicators apart is the ability to maintain accuracy throughout the width of the boom and achieve an even spread pattern, even in windy conditions. Fan options include a 1000 rpm PTO driven fan or a hydraulically driven 17 in. fan that operates at 4700 rpm.

The 8600 comes equipped with an 8 ton/260 cubic foot hopper, made of 409 stainless steel, which is designed to minimize fill stops and extend the life of the equipment. It can be equipped for two-product delivery, while the addition of an optional meter allows for the application of micronutrients or small seed application like canola or forage crops. The 8600 has a maximum application rate of 1000 lb/ac (Urea) at 8 mph, yet can apply as little as 50 lb/ac at the same speed with a mechanical drive and optional half rate kit.

The Valmar Airflo and BBI acquisitions add significant benefits and expertise to Salford Group, with an expanded product line that now includes: primary, secondary, and vertical tillage, air seeders, commodity carts, cover crop seeders, spinner-type fertilizer spreaders, air-boom applicators and granular applicators for fertilizer, insecticide, seed, seed inoculant and forage preservatives.

 

 

Published in Precision Ag

June 17, 2015, Regina, SK – Pesticide application has never been more important in Canada. Today's operators need to understand more than just how to operate a sprayer - one of the most complex and expensive agricultural machines. They also need to balance how weather, chemistry, plant canopies and many other factors affect performance and environmental fate.

To help make sense of it all, a new website, www.sprayers101.com, has been launched by two Canadian sprayer specialists.

"Applicators want to do the best job possible, and are always looking for information and advice," says Dr. Jason Deveau, application specialist with the Ontario Ministry of Agriculture, Food, and Rural Affairs. "We recognized a need to provide that information more effectively. That's why we developed a site that combines horticultural and field crop information."

Dr. Tom Wolf is a sprayer specialist based in Saskatoon with over 25 years of research experience in field sprayers. His company, Agrimetrix Research & Training, reaches thousands of applicators across Canada through presentations and workshops.

"Each year, producers spend more time in their sprayers than almost any other piece of equipment. Most of my clients' fields are now treated three to five times per year. The investment, and the stakes, are high," says Wolf. "Applicators deserve the best information on how to maximize pesticide performance and minimize environmental impact. Sprayers 101 is the ideal means to provide that information."

Deveau and Wolf use a variety of approaches to get their message out, relying on Twitter to invite applicators, agronomists and educators to Sprayers101. Facts, often spiced with humour, are delivered via stories, images, videos and apps. International sprayer specialists have begun submitting information for posting on the site, creating an unparalleled resource for all things "sprayer." The site is mobile-friendly and scales to the phones that applicators rely on for information gathering.

 

Published in Sprayers

Agrifac, a Dutch manufacturer of self-propelled sprayers, is expanding into Canada.

Agrifac has 30 years of experience in designing and manufacturing self-propelled sprayers. The company gives primary attention to an accurate spray application: "Every drop hits the right spot." Boom stability as well as techniques to increase the coverage of the crops are available on the machines of Agrifac.

Agrifac offers two types of self-propelled sprayers: the Condor and the Condor Endurance. The Condor is a versatile, high-quality sprayer suitable for demanding farmers. The Condor Endurance is the Condor's big brother, a reliable, high quality sprayer with extreme durability.

For more information, visit http://www.agrifac.com/condor.

 

Published in Sprayers

Equipment technologies are continually advancing to provide more opportunities to improve efficiency and effectiveness. But according to Jason Deveau, an application technology specialist with the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA), farmers do not have to buy a new sprayer to take advantage of the newest tools.

Deveau works with technology companies worldwide to learn about and test their latest sprayer advancements, and he says a multitude of aftermarket products can be purchased to improve operation and application.

Improving management
Oil- and water-sensitive papers are yellow cards that turn blue when sprayed. Deveau says the papers provide a cost-effective way to show coverage, spray drift and sprayer contamination. 

“By taking your time and using a clothespin and flag in the field, you can get a very good, immediate picture of how well you are doing,” he says, adding the tool can help farmers put recommended practices to the test by using the papers before and after changing methods, and analyzing the difference.

TeeJet Technologies offers two monitor products that Deveau sees as opportunities to improve operator management – the Sentry 6140 Flow Tip Monitor and the Sentry 6120 Droplet Size Monitor. The flow tip tool detects plugged tips as well as high and low flow errors or partial blockages. Deveau says using a minimum of three tips, sensors are mounted at each spray tip location without impacting flow. The sensors are linked to a touchscreen monitor, and errors are indicated by audible alarm and display notification. “This type of tool could replace hard-to-read floats, and could be used when planting, spraying and applying fertilizer.”

Deveau notes droplet size affects coverage and drift, and operators should be using catalogues to determine the average droplet size given their pressure and nozzle choice. He describes TeeJet’s droplet monitor as a catalogue tool, as it provides real-time droplet size display and highlights size changes with auto-rate controllers.

The Accu-Volume System, manufactured by Custom Concepts Mfg. Inc., claims to increase operator efficiency and Deveau agrees it answers the question of what exactly is in the tank. He says some gauges can be inaccurate by approximately 25 gallons, and sprayer grade can create a difference of up to 80 gallons during filling. The monitor, which includes a digital display in the cab and at the loading station, reduces the chances of running short or over-batching, and helps operators to avoid diluting existing solutions.

Deveau says Johnson’s Innovations manufactures Peek-a-boom, a remote controlled system for performing timed output tests safely and easily. Peek-a-boom allows operators to turn individual or all boom sections on and off from the cab or other nearby locations. ATI Agritronics Inc. has a similar smartphone application product called
AppliMax Spray Boom Remote Control.   

Nozzle technology
New in 2014, Pentair Ltd. announced the Hypro Duo React Twin Valve Nozzle Body. The product features a single nozzle holder and a rotatable four-way turret in one unit which Deveau says allows the operator to select either or both tips from the cab. He notes this tool could be convenient for operators aiming to switch from fertilizer to fungicide, from conventional flat fan to air induced or to dual fans.

Deveau says the Pentair Hypro Express Nozzle Body End Caps product could be applicable to more operators. “The caps are also air aspirators which could mean an 85 per cent faster shut-off valve operation.”

In terms of nozzle calibration tools, Deveau points to the SpotOn Sprayer Calibrator made by Innoquest Inc. He says this digital spray tip tester can be described as a vessel with two inside sensors. Once the meter is held under the nozzle at a slight angle, the tool displays how many litres, ounces or gallons per minute it is emitting within approximately 10 seconds.

Research and development
Deveau also reviews products currently in development or not yet available in Canada such as K-B Agri-Tech LLC’s Pattern Master, Harrie Hoeben’s Wingssprayer and Coraltec Inc.’s D30.

The creators of Pattern Master (patent pending) are claiming this product will change the way the industry looks at drift control. “It is a brush that is mounted in front of the nozzle, which means more coverage and less drift,” Deveau says, noting the brush has bottom bristles to diffuse but not block air flow. The product is currently being tested in the U.S. Deveau says initial trial results comparing brush to no brush show significant coverage improvement.

Wingssprayer has been available in Europe for four years and the manufacturer is considering expanding into Canada this year. Deveau says the product is a floating shield that blocks oncoming wind and flexes to lightly drag the crop surface which opens the crop canopy. Because the shield decreases the distance between the nozzle and crop, the creators claim Wingssprayer reduces dosage by up to 30 per cent.
Deveau says Coraltec Inc.’s D30 spray droplet size measurement system research is currently focused on industry applications, but the technology will be modified for agriculture.

“Spray mix viscosity can change nozzle output by as much as 30 per cent and also changes the volume median diameter (VMD),” Deveau says. “D30 could provide a way to check this quickly to ensure effective material deposition.”

As product technologies advance and new educational courses become available, information and free downloads can be found at www.sprayers101.ca, or by following Deveau on Twitter @Spray_Guy.

Published in Sprayers

After using a UAV to collect aerial images, Abuleil’s online tool allows users to label it according to their interests which was red clover ground cover in this study. Photo by Ammar Abuleil, University of Guelph.

The dream of using Unmanned Aerial Vehicles (UAVs) for precision agriculture took off faster than many developers could realistically keep up with, but researchers at the University of Guelph are hoping to close some critical technical gaps.

The UAV equipment now commercially available is highly sophisticated, featuring a wide range of image sensors that are capable of collecting a vast amount of information. So much data, in fact, that it becomes very difficult to make much use of it all. Which is why Ammar Abuleil, a Master in Engineering student, is trying to teach these flying machines how to produce something more than a pretty picture.

Under the direction of Dr. Graham Taylor, an expert in managing large data sets, and Dr. Medhat Moussa, who specializes in robotics, Abuleil has been creating an algorithm which filters the information collected by a UAV into a map that’s based on user-defined criteria. This would allow a farmer to upload the pictures taken of a field to the Internet and receive a colour-coded map back, indicating areas of weed infestation, flooding, canopy closure or any other label the farmer wanted to program into the model. For the purposes of developing the tool, Abuleil has been working on an assessment of red clover stands in wheat fields.
“What we’re trying to do is use remote sensing platforms and machine learning to try and make sense of what’s happening in the field without actually having to take samples,” Abuleil explains.

Abuleil worked with seven farms in the Guelph area, but only ended up collecting data from two because there were kinks to work out of the UAV’s system. In one particularly patchy 19-acre field, researchers asked the farmer to identify areas on a map of the field where the red clover stand achieved 100 per cent, 67 per cent, 33 per cent and 0 per cent ground cover. After that, the UAV flew over the field to collect visual data and the researchers collected 100 50-by-50 cm samples to verify the accuracy of the final image produced. Abuleil says using the classifications provided by the farmer as a scale and a very simple algorithm, the final image produced was 70 per cent accurate. With just a little more tweaking, Abuleil thinks he can improve those results to an accuracy rating of 80 per cent.

Although they focused on the red clover in the field, Abuleil says he has designed his algorithm to respond to any input reference so if the farmer wanted to assess the oilseed radish stand in that same field, it could do that too. “Because it’s a machine-learning algorithm, this program was not written specifically for this application, it can be applied to any application,” he explains. “So if a farmer, for example, circles ‘good moisture content’ and ‘bad moisture content’, then the algorithm will apply what the user circled and what the user labelled on the entire image.” The only thing that would limit what the machine could learn would simply be the quality of input data it collected. This is where the quality of the machine being used, and especially the quality of the sensors it can house, comes into play.

The UAV model Abuleil has been using to conduct his research is a Precision Hawk Lancaster Platform, which was selected and purchased for the university upon the advice of Loblaw Chair of Sustainable Food Production, Ralph Martin. Martin says he selected the model particularly because of the sensing options it offered. “From a research perspective, we wanted to have options to use sensors with as much capacity as possible,” he explains.

Many of the other different models he considered had fairly similar visual sensors, offered red-green and blue-green near infared sensors much like this UAV, and some also had the thermal sensors and LIDAR, which evaluates elevation, that it had. “But the reason we decided to go with Precision Hawk is that they also have a hyper-spectral sensor with a range from about 400 nanometres to 1000 nanometres,” he said. Since the platforms and sensors don’t mix and match, at least not at the time of purchase, it was a clear advantage to go with the only company that had been able to miniaturize this sensor. According to Martin, this is where the real advances will be in making UAVs a viable technology for precision agriculture.
“With the basic visual sensors there are a few things you can do,” he says. “You’ll get a pretty quick estimation of whether or not there are things like deer damage; or in the spring you might want to get an idea of how wet it is, but that has limited use.”

Testing these new sensors to ensure they deliver what they promise, however, is an important part of developing the technology, work that Abuleil and his supervisors are contributing to. “Groundtruthing,” as they call it, costs significant man hours. But Martin’s sure the work being conducted will be worth the wait.
“We have to keep testing until we’re confident that what we see from the sky is really what we can measure on the ground,” Martin emphasizes. “It takes a little more time than some people would like it to take, but we don’t want to oversell the potential of UAV technology because we feel that we still have a lot of research to do.”

Martin got involved with UAV research in the first place because he saw a clear fit with his mandate to engage in research activities most likely to increase the future sustainability of the agricultural industry. If given the time and resources to properly develop these new tools, he believes farmers could be well positioned to get just the right amount of crop inputs exactly where they’re needed, attaining economic and environmental benefit all around. Nicole Rabe, land resource specialist with the Ontario Ministry of Agriculture, Food and Rural Affairs, sees similar potential, if only problems in using the technology could be eliminated. For example, she says, development really needs to reach the point where most agronomists can receive real-time data from the UAVs. For most, uploading massive data files into a van and waiting a day or two for a map is still far less efficient than walking fields.

“The volume issue is going to go away very quickly with folks like Ammar and his supervisor Graham Taylor working on industry software developments around real-time processing of UAV imagery after the photos are acquired,” she says. “That’s probably going to go away before you and I know it.”

Rabe strongly believes the real power of UAV technology is the mapping element. There is a real difference between eye-balling everything and estimating from ground references as opposed to holding a map in hand that clearly identifies the exact boundaries of a trouble spot.

“We can have a continuous map of the entire crop, you can calculate acres, you can quantify product, based on the decisions we made on that image,” she says. “It’s another map tool that allows us to quantify what we’re doing, so maybe we don’t have to put fungicide on the whole field or maybe we only have to spread a micronutrient across part of the field because the UAV image brought the scout to the region of the field that needed the farmers attention.”

The environmental and economic benefit of using the imagery marries perfectly with precision ag philosophies. So although it may still take time to realize the full potential of UAV imagery as another precision agriculture tool, it does remain a goal worth working toward.”

Published in Precision Ag

In theory, in-season fertilizer applications that add just enough but not too much nitrogen can enhance profits, increase nitrogen use efficiency and reduce environmental impacts. In practice, determining the right rate can be challenging. On-the-go sensor-based systems like GreenSeeker offer a way to more accurately estimate rates and to apply those rates as the crop’s nitrogen needs vary across the field.

“One of the major challenges that growers face in managing nitrogen is dealing with variability. There’s variability in space within the field and between fields, and changes in time throughout the growing season, and from one season to another. This is due to variations in landscape characteristics, soil characteristics, weather conditions and grower practices,” says Dr. Olga Walsh, a cropping systems agronomist specializing in precision agriculture at the University of Idaho. “Using this sensor technology helps account for these types of variability, allowing much more informed decisions.”

With these in-field optical sensor systems, growers can fine-tune in-season nitrogen rates based on real-time conditions. For example, growers could replace nitrogen lost to the environment earlier in the growing season, avoid applying extra nitrogen where it’s not needed, and add extra nitrogen if the crop is performing better than expected.

“In North Dakota, we have a problem with nitrogen loss due to leaching during wet years. We have a problem in high clay soils with denitrification, which is gas loss of nitrogen. So side-dress nitrogen is important. But what should you use for a rate? Do you just guess?” says Dr. Dave Franzen, an extension soil specialist at North Dakota State University. “Using these sensors is the most scientific way to make a rate recommendation that we’ve ever had.”

How the sensors work
Examples of these sensors include GreenSeeker, CropSpec, OptRx and Crop Circle. They are called “active” optical sensors because they emit their own light. Franzen says, “The strength of that is that you can use an active optical sensor at midnight or on a cloudy day or on a day that has sun with clouds wafting by. Those are things that interfere with satellite imagery, aerial photography and drone imagery [which all involve ‘passive’ sensors that measure reflected light originally emitted by the sun].”

He explains that the sensors emit their light in coded pulses, similar to the technology of a garage door opener or a television remote. The light code is similar to the UPC black and white lines on most retail packaging, although instead of black and white colours, the bands are different time-lengths of light-on, light-off intervals.

For variable rate fertilizer applications, the sensors are attached in front of the fertilizer applicator unit and are integrated with the application system. The sensors emit specific wavelengths of light onto the crop canopy, and the canopy reflects some of that light back to the sensors. The sensors determine the difference between the emitted and reflected light. The difference is affected by the crop’s health; for example, healthier plants tend to absorb more red light and reflect more near-infrared light.

The sensors do not directly detect nitrogen. “They tell us how much biomass has been produced, which is an overall evaluation of how healthy the plants are,” Walsh explains. “Research shows biomass production is highly correlated with final yield for many crops – wheat, corn and others. So these sensors allow accurate estimation of the crop’s yield potential and how responsive the crop is to nitrogen.”

Franzen notes that sensors that use red/near-infrared light evaluate two-dimensional biomass. “Sensors that use red-edge/near-infrared light evaluate foliage tint.”

Most of these sensor systems require a nitrogen-rich strip as a standard for comparison with the rest of the field. “You apply a base rate of nitrogen to the field [at or near planting time], and in addition, you apply a little more nitrogen than you think the crop would need to a small portion of the field, the width of the applicator and maybe 100 feet long. That small area is your nitrogen non-limiting standard,” says Franzen. For example, a grower might apply about 1.5 to two times the recommended rate to create the nitrogen non-limiting area.

For an in-season nitrogen application, the first step is to get a sensor reading of the nitrogen non-limiting area. The average reading for that area is entered into the spray controller. “If the sensor readings in the rest of the field are within about five per cent of the reading in the nitrogen non-limiting area, then there is no need to apply any additional nitrogen,” says Franzen. “If the difference is greater than about five per cent, then the sensor will use a formula to rapidly calculate the nitrogen rate to apply to that part of the field, and it will tell the applicator what to apply.”

One downside of this technology is that the applicator would need to drive through each field. So Franzen and his colleagues are working on using satellite imagery as an initial screening tool. For instance, if the satellite imagery indicates a field needs little or no extra nitrogen, the applicator could simply skip that field.

These sensor systems can be expensive, so how many sensors do you need? Franzen suggests starting with one sensor. “Dr. Bill Raun from Oklahoma State University, who first introduced this technology, initially developed a system with a sensor and an array of nozzles about every three feet to apply variable rate nitrogen on winter wheat. It freaked people out because it’s a huge step.

“If a person wants to dive into that end of the pool, feel free, but what I am advocating right now is one sensor in front of the applicator controlling the boom. However, 20 years from now, when people have been using this technology for a while and are comfortable with it, I think there will be a sensor for every row,” says Franzen.

The sensors measure the reflectance of both weeds and the crop, so the weed population needs to be low for an accurate estimate of the crop’s nitrogen needs. If a crop has some other problem, like a disease or an insect infestation, the grower could assume the same problem is also affecting the nitrogen-rich area, as a way to simplify the situation. One of Walsh’s graduate students is working on identifying and distinguishing between the effects of nitrogen stress and other stresses, like disease, insect and water stresses, in the sensor readings.

Another problem to watch for is sulphur deficiency. “We’ve found that the sensors are very good at detecting a sulphur deficiency in the field. When nitrogen is deficient, sulphur is mobile in the plant so the [sulphur] deficiency isn’t nearly as bad. But when sulphur is deficient and you have plenty of nitrogen, then that intensifies the sulphur deficiency. So sometimes our high nitrogen plot was the yellowest plot. That can only happen if there’s a sulphur deficiency,” says Franzen.

“If that happens, then the grower needs to apply some sulphur as soon as possible and then wait about a week before going back in to do the nitrogen application.”

Algorithms matter
These sensor systems use formulas, or “algorithms,” to convert the information from the sensor readings into nitrogen rates. The algorithms vary depending on such factors as the region, tillage practice, soil texture, crop type and growth stage, and sensor type. An algorithm developed for one region will probably not accurately predict nitrogen rates for a different region.

“Developing these algorithms takes a lot of time and effort,” notes Walsh. For the past 3.5 years, she has been leading a team to develop algorithms for Montana wheat varieties and growing conditions. “The more field locations and the more data you collect, the better your algorithm will be. However, once you’ve done the work, it is easy to convert that knowledge into software. Then it becomes part of the package that comes with the sensor unit or on-the-go variable rate system, so growers can use it right away.”

Franzen recently completed a study to develop algorithms for corn in North Dakota for GreenSeeker and Crop Circle sensors. “One of the basic principles of site-specific agriculture is that it is always site-specific per scale. Even within North Dakota, for just one type of sensor, I have four different algorithms. That is partly because of regional differences: the western part of our state, southwest of the Missouri River, has different soils, different [nitrogen supplying] capability and a different environment than the eastern part,” he says.

“I’ve asked my computer science colleagues to develop a machine learning tool in the next few years, so farmers would use these [regional] algorithms as a starting point and then continually add data from their own farm and gradually morph the original algorithms into algorithms specific to their farm.”

For the Canadian Prairies, the late Dr. Guy Lafond, who was with Agriculture and Agri-Food Canada, and Chris Holzapfel, research manager at the Indian Head Agricultural Research Foundation, worked on GreenSeeker algorithms for spring wheat, durum wheat, canola, malting barley and oat, for the Brown to Dark Brown soil zones and the Thin Black to Black soil zones. The algorithms require the grower to enter the number of growing degree days, using a base temperature of 0 C, from seeding to the day of sensing.

As part of their research studies, Lafond and Holzapfel compared various approaches to nitrogen applications including: applying 100 per cent of the anticipated nitrogen need at seeding; and applying some of the nitrogen at seeding and some as a variable rate application with a GreenSeeker system. Overall, both systems had the same crop yields, but the variable rate/GreenSeeker approach achieved those yields with less nitrogen.

There can be challenges in applying in-season nitrogen in a timely manner, especially if herbicide or fungicide applications need to be made during the same time period. As well, dry conditions after the nitrogen application will delay the availability of the fertilizer to the crop. Lafond’s and Holzapfel’s research indicates that, for the cereal and oilseed crops they studied, at least half to two-thirds of the anticipated nitrogen requirement should be applied at seeding. Growers also need to consider such factors as crop price, fertilizer cost and application cost to decide whether an in-season nitrogen application would make economic sense for their situation.

Walsh says the return on investment for an on-the-go sensor system depends in part on the grower’s objectives. “They might want to decrease the amount of nitrogen they apply to save money on fertilizer. Or they may want to distribute fertilizer inputs more precisely in the field to improve crop yield and quality.”

She notes, “Normally, the initial investments in these sensor-based systems are paid off within one or two growing seasons.”

Franzen expects adoption of this technology in North Dakota to be a gradual process. “Any kind of site-specific movement forward seems to take about 15 years. I’ve seen it with yield monitors and with zone and grid sampling. This sensor technology is the next thing. In about 15 years, it will just be something that people do,” he says.

“We now have several sensors on the market, and more and more people are making some use of them. [And we have algorithms to get growers started with sensor-based nitrogen applications.] It will take some time to get some people’s heads around it, but this is where we need to go with side-dress nitrogen for many of our soils in North Dakota.”

Walsh thinks precision agriculture will eventually become the standard practice for agriculture. “One of the Idaho growers put it very well. He said: ‘Growers who think in terms of sustainability and staying competitive cannot afford not to use this kind of cutting-edge technology.’ Sustainability includes all of the aspects of crop production – maintaining or increasing yield, improving crop quality, sustaining crop productivity and minimizing negative impacts on the environment. The sensors help in all of these aspects.”

 

Published in Corn

To map a field, the UAV flies over a field in parallel passes and takes photos at regular intervals.
Photo by Janet Kanters.

Does using an unmanned aerial vehicle (UAV) make sense for your crop operation? UAVs, also called drones or unmanned aerial systems, are available as fixed-wing types, like little airplanes, or rotor types, like little helicopters. They are catching the attention of Prairie crop growers and specialists who want to see how well they work for crop scouting and field mapping, and how the costs compare to the benefits.

UAVs for weed and disease issues
In Alberta, a project is underway to evaluate the use of UAVs to generate field maps to help in making decisions on weed and disease management. Dr. Chris Neeser, a weed research scientist with Alberta Agriculture and Rural Development (AARD), is leading the project. He wants to develop a set of procedures for acquiring and processing high-resolution UAV imagery and to assess the usefulness and economics of this tool.

To map a field, the UAV flies over the field in parallel passes and takes photos at regular intervals. Imagery software is then used to stitch all the photos together to create a map of the whole field.

The fixed-wing UAV used in Neeser’s project is a prototype developed and flown by Jan Zalud of JZAerial in Calgary. Neeser says, “It can fly for about 15 to 20 minutes before you have to change the battery. That is just enough time to map a quarter section, taking about 120 images per quarter and flying at an altitude of about 600 feet.”

A small digital camera is attached under the UAV’s wing. The camera’s filters have been modified to capture near-infrared light. “Instead of the red, green, blue spectrum, we get the near-infrared, green, blue spectrum,” explains Neeser. “Vegetation reflects near-infrared wavelengths better than the other wavelengths, so it allows you to do NDVI (normalized difference vegetation index) mapping.”

Healthy plants reflect more near-infrared light than stressed or dead plants, so NDVI maps can be used to evaluate factors like plant stress due to disease, drought or low available nitrogen. So, with proper interpretation and analysis, the maps could help with decisions on variable rate applications of inputs.

Neeser explains that because the photos were taken from a height of 600 feet, the imagery has a resolution of about six centimetres to the pixel; that is, each image pixel covers a 6 cm by 6 cm area on the ground. So the UAV imagery can show things like crop rows and any seeding errors in those rows, but not the individual leaves on a plant. Problems that occur fairly uniformly across a field are hard to detect on the imagery, but patchy problems, like a patch of weeds or diseased plants, are easy to see.

“To detect greater detail, the UAV could fly lower. But it would take longer to get coverage of the whole field, longer to analyze the imagery, and more processing power. So it’s a trade-off,” he says.

In co-operation with several southern Alberta crop growers, the UAV was flown over 12 fields and six crop types in 2014. In the coming months, Neeser will be analyzing the maps, comparing them to what was actually happening on the ground, called “ground-truthing,” and evaluating the costs and benefits of using UAV imagery.

The project is funded through the Alberta Crop Industry Development Fund, with funds from the Alfalfa Seed Commission, Alberta Pulse Growers Commission, Alberta Wheat Commission, Western Grains Research Foundation, Alberta Canola Producers Commission and Potato Growers of Alberta.

Quadcopter explorations
In Manitoba, Rejean Picard, farm production advisor with Manitoba Agriculture, Food and Rural Development (MAFRD), has been trying out a DJI Phantom 2 quadcopter (a helicopter-type UAV with four rotors).

He has been using the Phantom 2 for freestyle flying, guiding it as it flies over the field. “Because it’s freestyle flying, it’s very quick to start and fly and collect imagery and be back to the operator in minutes.” The UAV’s camera is a GoPro model that can take still colour images and HD video.

“A UAV gives you that eye-in-the-sky perspective, so you can see much more of the field than you can standing at ground level. I also like that you can collect pictures of a field over time to see how things change, and you have a permanent record of what the field looked like at different times of the year,” he notes.

Picard especially likes his system’s ability to receive live images while the drone is flying. “With the live on-screen display, you can see what the camera is seeing. For example, if the field is wet so you can’t drive through it, and you want to see the extent of water damage or flooding in the field, then the live images allow you to do that.”

Learning to fly his quadcopter took some practice, especially to land it without damaging the rotors. Picard says it can fly for about 20 minutes before the battery needs to be recharged, and it can operate in wind speeds up to about 40 kilometres per hour. “It is GPS-driven and designed to hover. With the GPS, it will find and maintain its position, within a certain range [even in breezy conditions].” The UAV weighs about one kilogram.

“The costs for my unit include the UAV itself with the gimbal (the supporting arm that holds the camera), which is about $1,000. The camera is another $400. The live on-screen display is about $400 to $500. So the total cost would be between $2,000 and $2,500, tax included. For that you get an effective entry-level UAV for growers,” he notes.

One of the tools Picard has been playing with recently is imagery analysis software called Assess, which costs about $300. “The still images that I collect with my UAV are distorted somewhat because the camera uses a wide-angle lens. But, by using the software and knowing the field’s size, I was able to differentiate the different colours in the images, such as thinner patches versus thick green patches. And I was able to determine fairly closely what proportion of the field had a thin plant stand, which could be drowned-out spots or a knoll where there is little growth,” he explains. “So with other tools, a person can use even this basic UAV effectively.”

Geo-referenced mapping and scouting
Jeff Kostuik, a diversification specialist with MAFRD, has been experimenting with a fixed-wing UAV. He says, “We run a small applied research farm here [at Roblin] with the Diversification Centres in Manitoba, and we’re always looking for different ways of gathering data. I thought being able to fly the drone on a regular basis would be a good fit for what we’re doing. But more importantly, I wanted to figure out how using a drone might fit for regular farmers, would it be worth the cost, and how would they get a return on investment.”

He is using one of senseFly’s earlier introductory models called the swinglet CAM. “We’re able to fly our UAV only if the wind is under 20 km/h, but senseFly’s newer models perform quite well in winds up to 40 to 45 km/h. Depending on weather conditions like wind speed and temperature, ours will stay in the air from 10 to 20 minutes; newer models can stay up longer.”

Kostuik’s system costs about $20,000 to $25,000. It has GIS (geographic information system) capability so it can create geo-referenced imagery for precision farming uses. It can provide regular photos, as well as near-infrared and NDVI imagery. It weighs about 0.5 kg.

He says the swinglet CAM is extremely easy to fly. “The computer does all the work for you. You do pre-flight programming for exactly what you want. The resolution you want will determine how high it will fly and the amount of [photo overlap between passes]. Then you just shake the drone three times to start the motor and throw it into the wind. It automatically flies your programmed route. When it’s done, you basically hit ‘come home’ on the computer, and the plane lands within about 15 metres of where you are.”

He notes, “You can view the pictures individually once the plane lands – you just take the SD [memory card] out of the UAV and put it into your laptop to view them. But to stitch all those photos together to get a map of the entire field takes a few hours.”

To Kostuik, the most obvious use for UAV technology is crop scouting, especially when it is difficult to walk or drive into a field. On the images that Kostuik is obtaining, it’s easy to see things like crop rows, lodging, weed patches and cutworm-damaged areas.

However, he emphasizes that the NDVI images need to be ground-truthed to be sure they’re interpreted correctly. “We’re finding that you still can’t beat boots on the ground. A drone can be a tool in the toolbox, but it is not something that you can rely on [by itself] to tell you what is going on in the field,” says Kostuik.

On the plus side, he says UAV imagery is great for targeted on-the-ground scouting.

UAVs and the bottom line
UAV technology is pretty cool, but will it improve your bottom line? “You need to look at the costs and the type of information the drones can glean from the field and then how you’ll deploy that information to make more informed business decisions,” says Nevin Rosaasen, a research economist with AARD. “At the end of the day, it’s how you leverage it to put more dollars in your jeans.”

One consideration is how the costs and benefits of UAV imagery compare with other ways to get information about your fields. Compared to satellite imagery and conventional air photographs, UAV imagery has advantages like higher spatial resolution, better timeliness and the ability to tailor the data collection to a specific site. Compared to boots on the ground, UAV imagery provides quick, easy access to the whole field and helps improve the efficiency of on-the-ground scouting. On the other hand, there’s the cost of purchasing and repairing the UAV system, the time to learn to use it, and the time to operate it and analyze the imagery.

The time needed to learn how to fly a UAV varies; some are easy to learn and others are a little more complicated. All UAV operators must follow Transport Canada’s air safety requirements (see sidebar).

The cost of UAVs varies quite a bit. “An entry-level recreational drone with two cameras, for instance, is as cheap as $350. For drones that provide more accurate information, with higher resolution photo and video images, you’re looking at a base entry of around $3,000 to $4,000,” says Rosaasen. Also, “some UAV parts can be costly if you have some crashes as you learn to fly it. And if your drone goes down in a fairly tall or dense crop, it can be tough to find.”

Systems with the GIS capabilities needed for precision farming applications are more expensive and require a greater time investment for imagery analysis.

“We’ve created a bunch of very nice photographs, but what does the imagery mean to the producer and how does he make money from that? I’m not a GIS specialist and all that is a steep learning curve for me,” notes Kostuik. “It’s more suited to people who are a little more advanced in precision farming and variable rate applications. You can generate a prescription map fairly easily and quickly, and it’s real-time as opposed to satellite imagery. Our imagery has about 6- to 10-cm pixel resolution, whereas satellite imagery has about 30-m pixel resolution, so ours is a lot more precise.

“If you have the ability to use those prescription maps, then this technology could to save you money. If you’re using it for crop scouting, it could save a little time, but not necessarily a lot of time.”

Kostuik thinks a higher-end system, like his $20,000-plus system, would be cost-prohibitive for an individual farmer to purchase, but it could make economic sense for an agronomist who is providing precision farming services for a number of clients.  

Neeser has a similar view. “I can see crop consultants using this as one of their tools to collect information about their clients’ fields. They would need to import the UAV images into a GIS program and overlay those over images with other information, like yield maps, fertilizer application maps, soil maps and so on. In conjunction with all the other information, the UAV imagery could be valuable to help make better decisions, as they accumulate several years of these images and see the differences depending on what crops are grown,” he says.

“But combining the UAV imagery with GIS would require a substantial investment of time to learn how to do it, because it requires some specialized knowledge. And it takes time to get the images and analyze them. Also, there is a significant risk with this kind of equipment; it could crash, for instance.”

Neeser expects UAV use in agriculture to continue to increase. “It is rapidly developing technology, so it looks like we’ll see UAVs being used more and more in the future.”

Rosaasen says the use of the technology provides a lot of opportunity to revolutionize the way crops are produced. “Thinking out to 2025 or 2030, drones could be delivering small shots of fertilizer or a specific herbicide to individual plants. We have all the tools to do that; we just haven’t put it all together in a complete package yet. I think producers will find innovative ways to deploy this technology faster than analysts can speculate on how it might be used. If there’s a way to make a dollar, farmers will figure out how.”

Operating your UAV safely and legally
Anyone operating a UAV in Canada must follow the rules set out in the Canadian Aviation Regulations and must respect all federal, provincial/territorial and municipal laws related to trespassing and privacy.

Until recently, use of a UAV for work purposes, including things like crop scouting, required a Special Flight Operations Certificate (SFOC) from Transport Canada. However, in November 2014, Transport Canada brought in two exemptions that simplify small UAV operations.

Under the new exemptions, an SFOC is no longer required for work use of UAVs under 2 kg and certain operations involving UAVs under 25 kg. However, operational limitations apply to both these exemptions (for example, restrictions related to flying height, distance from aerodromes, and type of airspace in which the UAV operation is taking place). Anyone wishing to operate a UAV outside of these limitations must still obtain an SFOC. In addition, the exemptions apply only to operations within visual line of sight. This means the pilot or his visual observer must maintain visual contact with the aircraft, without any aid such as binoculars, to maintain control and decisively see and avoid other aircraft or objects.

Transport Canada is also simplifying the application process and reducing the time it takes to issue SFOCs for larger UAV operators.

“We’re trying very hard to give UAV users the easiest possible access to being able to operate, while balancing that with the need to make sure things are safe for people on the ground and people in the air,” says Martin Eley, director general of Civil Aviation at Transport Canada. “So we’re encouraging people to understand and live up to their responsibilities and become familiar with the basic rules of the air, because UAV operators are sharing the air with people in larger aircraft.”

Visit Transport Canada’s website (www.tc.gc.ca) for more details on flying your UAV safely and legally.

 

Published in Precision Ag
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