The tiny, grey weevil was the greatest pest problem of the 2025 growing season, said Manitoba Agriculture entomologist John Gavloski.

“My poor summer students this year [found] 1,739 weevils in our 27 fields,” Gavloski told an audience at the 2026 Manitoba Ag Days in Brandon in January. “They were over double the economic threshold.”

WHY IT MATTERS: After a few years of minimal presence in Manitoba, cabbage seed pod weevil populations boomed in Manitoba in 2025 — in one case to twice the economic threshold.

Cabbage seed pod weevil is a three- to four-millimetre insect that lays its eggs inside young canola pods where its larvae feed on seeds. It overwinters as an adult under leaf debris and moves into flowering canola fields in late June and early July.

Gavloski’s survey results showed a dramatic population boom in 2025. In one field north of Carman, the count was as high as 226 weevils in a 25-sweep sample.

The economic threshold for cabbage seed pod weevil damage is 25 to 40 weevils per 10 sweeps, or 63 to 100 in the 25-sweep samples Gavloski’s survey uses. That Carman-area field was more than double the economic threshold and was treated once the population was confirmed.

Prior to 2025, the highest single-sample count Gavloski had recorded in his surveys was six weevils.

The pest has also been spreading eastward across the province. While populations were historically confined to southwestern Manitoba, weevils were detected as far east as the Ste. Anne area in 2025.

Scouting the critical first step

The weevil arrived in Manitoba from Alberta, where it had spread after an introduction to southern British Columbia in the 1930s. By 2017, it was first detected in Manitoba near Morden.

Survey counts remained very low for years before last season’s surge.

“We went from low counts to really high counts in the Carman area, going from 2024 to 2025,” Gavloski said.

“So bottom line, watch your fields. Start learning how to scout your fields.”

Scouting is complicated by the weevil’s defence mechanism: when disturbed, it drops to the ground and plays dead. Finding a three-to-four-millimetre grey insect on bare soil is no easy task.

“Just walking the field without a net, you could have a lot of them there and really not know it,” Gavloski said.

He recommends producers use a sweep net and conduct 10 sets of 10 sweeps: five near the field edge, five farther inside, during the flowering period in late June and early July.

Research from Alberta suggests that trap cropping (seeding the outside rows of a field one to two weeks earlier than the main crop, then spraying only those edges) can concentrate weevil populations and provide effective control while protecting pollinators in the main field.

Seeding date is another factor. Earlier-seeded canola, which flowers first, attracts significantly more weevils than later-seeded crops.

While cabbage seed pod weevil dominated the conversation, Gavloski noted several other insects that warranted attention across Manitoba during the 2025 season.

Flea beetle damage lessens, cutworms trend down

Flea beetles remained a concern but caused less economic damage than in recent years — largely due to a warm, moist spring.

“I don’t think it was because the flea beetle populations crashed,” Gavloski said. “I think it was because we finally got a season where people seeded the canola, it came up, and it seemed to have enough moisture and enough heat to get you from seedling to three to four leaf stage relatively quickly.”

Cutworms were still present and some fields were treated, but Gavloski said populations appear to be on the downward side of a cycle. He compared cutworm population dynamics to a bell curve: populations build, peak for a few years, then taper off, often driven by natural parasitoid activity. The worst years were 2020 and 2021.

“We’re kind of on that downward curve,” he said. “Populations have dropped off a little bit.”

Western and southwestern Manitoba bertha armyworm hotspots

Bertha armyworm became a regional concern, particularly in the western and southwestern parts of the province around Gladstone, Neepawa, Holland and Brandon. Some activity extended toward the central region.

Traps Gavloski monitors showed many locations crossing into the “uncertain risk” category during the summer. He noted some positive signs, however. There were reports of armyworms found dead on top of plants — a sign that naturally occurring viral and fungal pathogens had gotten into the population.

“If they’re up on the top of the pods in the day and they’re not moving, that’s a good thing. They’ve got pathogens. You want that,” he said.

Diamondback moths of low concern

Diamondback moths stayed relatively quiet in western Manitoba but caused some problems in the eastern part of the province in late summer. Populations are believed to have blown in on winds in late May and early June.

“They don’t overwinter well in the Canadian Prairies,” Gavloski said. “They’re just kind of getting blown in almost randomly on winds, and they get dumped wherever the winds dump them.”

Lygus bugs caused scattered economic-level infestations, primarily in the Interlake, and some fields were treated. Unlike the chewing insects on the list, lygus bugs pierce plant tissue with a beak-like mouthpart, inject enzymes and feed on the juice. They particularly target buds, flowers and young seeds.

On the positive side, Gavloski said that grasshoppers and aphids were largely non-issues across the province in 2025, with very little spraying required for either pest.

“Every year, weather drives things,” Gavloski said. “We get things that go up, we get things that go down.”

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For example, Gavloski cited flea beetles, which could damage canola. “If [canola] plants sit in that seedling stage for a long time, the seed treatment wears out,” and farmers would then need to apply a foliar spray, he said.

“If seeding into ground that is warmer and has good soil moisture, you may get quicker germination and quicker seedling growth. That might reduce the risk of excessive flea beetle damage.”

Overly wet soil could hinder plant growth, which would lead to a greater chance for insect pests to do damage, he said. However, the soil going into mid-May would be warmer than in late April/early May, giving crops a chance to germinate quicker.

The entomologist cautioned that grasshoppers could be another pest this year, but the varieties that do pose a risk are currently in the egg stage.

“The eggs can handle being under water for days, but juveniles after being hatched cannot sit in water or they will drown,” Gavloski said.

Soggy conditions in Manitoba coupled with cooler-than normal temperatures could slow grasshopper emergence, he said, but stressed the need to always be vigilant.

“We still want to be on guard just in case we do get that big hatch,” he warned.

While bertha armyworms were not a problem in Manitoba last year, he said traps will still be set and monitoring is important.

“They often go in cycles where they build up and are bad for a few years, and then levels drop off,” Gavloski said.

No insecticides were used in the provinces last year for bertha armyworm, he said, and there’s nothing suggesting a large outbreak ahead.

Gavloski also advised growers to keep watch for diamondback moths blowing in with winds out of the south, and for armyworms migrating from the south.

— Glen Hallick reports for MarketsFarm from Winnipeg.

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That’s the advice Tammy Jones, Manitoba Agriculture and Resource Development’s (MARD) weed specialist gave in an interview following a Crop Talk webinar July 15. (Jones’ last day with MARD was July 17. She joined Corteva July 20.)

It takes at least three canola plants per square metre to make it worthwhile to apply a herbicide to control volunteer canola in soybeans, Jones said, referring to research conducted by University of Manitoba weed scientist Rob Gulden.

Why it matters: Canola volunteers in soybeans are unsightly, but the cost of trying to control them at the flowering stage in some cases may end up being more about revenge than saving money.

Three canola plants per square metre isn’t a lot, but it doesn’t take many flowering canola plants to make a field look messy, Jones said.

There’s a lot to consider. How much will the volunteer canola affect soybean yield? How much will the herbicide and application cost? Are the canola and soybeans at the right stage for the herbicide being applied? How much will soybean yields be affected by driving through the crop?

If the canola is flowering and in high enough numbers across the field, much of the damage to soybean yields has probably already occurred, MARD said in its July 15 Manitoba Pest Update.

Usually the volunteer canola Manitoba farmers have is Roundup Ready so glyphosate isn’t a control option. But there are several other herbicides that can be used, but with caveats, Jones said.

Bentazon (the active ingredient in Basagran) is one, but it’s registered to control canola up the eight-leaf stage, “…so if it’s flowering you’re not going to necessarily kill it in certain growing conditions,” Jones said. “It’s still a good product and will do a job, but it may not be as perfect as you want it to be.”

There’s also a risk the sprayed canola will just be set back, complicating the soybean harvest, she added.

“It may be just worth it to bite the bullet and let that canola mature and be out of the way rather than delaying its maturity by spraying it with a sublethal application and having it still green when you’re trying to harvest,” Jones said.

Reflex and Flexstar also can control volunteer canola in soybeans but not at the flowering stage, or outside of the Red River Valley, the Manitoba Pest Update says.

Imazethapyr (Pursuit, Phantom, Guardsman Gladiator or MPower Kamikaze) can’t be used either because the pre-harvest interval for soybeans is 85 days.

“The pre-harvest interval is the thing that worries more than anything,” Jones said.

“It’s just not worth the risk as far as I am concerned.”

It’s best to control volunteer canola early, but Jones said farmers don’t have a time machine. The next best thing is taking action in the future, including reducing canola losses at harvest time and following canola with crops that allow for easier canola control either pre-plant or in-crop.

“Nobody wants a messy field,” Jones said. “It’s annoying to look and it has management considerations for future years (by adding more canola seed to the field’s weed bank). There’s lots to think about. It’s not an easy decision.”

Worms & moths

Now is a good time to scout canola for Bertha armyworms and diamondback moth, MARD entomologist John Gavloski told the Crop talk webinar July 15.

Traps are up to monitor adult Bertha armyworms, with the highest population so far in the southwest around Killarney, he said.

Gavloski recommends checking for the pest using a three-sided 50-by-50 cm square (the fourth side is left open so it can be slipped around the plants). That area works out to be a quarter square metre.

“Give the plants (within the square) a shake just in case there are any caterpillars on the plants,” he said. “They should all be on the ground. Then start searching on the ground in that quarter metre square. Most of the caterpillars, if they are there, will be under trash debris and cracks in the soil.”

Research has determined for every caterpillar per square metre, canola yield is cut by 0.058 bushels per acre, Gavloski said.

“So if you’re not afraid of mathematics you can do the math and figure out how many caterpillars would it take to equal a spray (in cost),” he said. “So if you had 20 caterpillars per metre squared, on average, you’d be losing about 1.16 bushels per acre. If that’s going to equal a spray application that’s going to be your threshold. If that’s not quite enough to equal a spray application you might want to go higher with your threshold.”

Find more information on Bertha armyworms and thresholds at the Manitoba Agriculture website.

To assess diamondback moths in canola Gavloski recommends using a three-sided one-foot square. Shake the plants over something that can catch the insects and count them.

Spraying is economic when there are 20 to 30 diamondback moth larvae per square foot, he said.

“Now don’t get too frightened if you start seeing borderline levels at flowering,” Gavloski said. “At the flowering stage the plants can compensate quite well from a little bit of feeding, especially if you have good soil moisture, but when you get into the podding stage just be careful if they start moving onto the pods and doing feeding. That’s what they (plants) can’t compensate for.”

Find out more on diamondback moth at the Manitoba Agriculture website.

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Manitoba Agriculture and Resource Development has noted exponentially higher counts of diamondback moth in those areas, something provincial entomologist John Gavloski has linked to windy weather in June blowing adult moths into the region.

“Especially that eastern region, they were getting some quite high numbers,” Gavloski said.

Why it matters: High winds out of the south earlier this year may have left an unwelcome legacy: diamondback moth.

The province counted 400 moths near Lac du Bonnet as of July 2, the highest of any region in Manitoba, while traps in the rest of eastern Manitoba have reported anywhere from 189 adults in Beausejour to 372 in Whitemouth.

Traps in the Interlake fell only slightly below those numbers. The Gunton area saw the bottom of that range, with 106 adult moths this year, compared to 241 trapped in Warren.

Only one trap in The Pas rivalled numbers seen in the east and Interlake, counting 123 moths this season, far lower than the 30 to 50 adults registered elsewhere in the northwest.

In comparison, traps in the southwest topped out at 15 moths near Hamiota, while central Manitoba range from 12 in Winkler to 57 farther north at Gladstone.

Those numbers do not, however, automatically mean that producers will have to spray for the pest, Gavloksi cautioned.

“The trap counts are kind of an early warning system,” he said. “We put up the traps to try and pick up what is blowing in and give people a heads-up to get them out scouting. We don’t want them making control recommendations or thinking there’s going to be an outbreak because of what the trap counts are saying.”

Poor egg-laying conditions or high populations of parasitoid insects can sometimes chip away at larvae numbers, even if a large wave of adults has been noted in an area, he said.

The same southerly winds that blew moths into the province during the first three weeks of June may have also hindered egg laying, according to Gavloski.

Meteorologists have said the period between mid-May and mid-June this year was the windiest in Manitoba since 1990, the Manitoba Co-operator recently reported. The province saw sustained winds over several weeks during that time, with several days clocking gusts over 70 kilometres an hour. Peak gusts in some areas were significantly higher, including 114-kilometre-an-hour winds by Eriksdale and 120-kilometre-an-hour winds near Somerset.

The east, however, saw peak gusts at about half that strength, ranging from 51 to 67 kilometres an hour.

“We did have a lot of very windy conditions, which would have brought them in, but they’re going to lay more eggs on warm, calm, dry evenings, so if it’s too cool or too windy, it will decrease their activity,” Gavloski said. “There were a lot of windy evenings, but there were probably enough calm ones too that I think it’s good for people to be out looking.”

One of the field pests that does not overwinter well in Manitoba, diamondback moth problems usually have little to do with populations the year before. Manitoba Agriculture and Resource Development links diamondback moth problems with the number of overwintered moths farther south, winds out of the south needed to bring the pests into Manitoba each year, and warm summer temperatures.

Gavloski says he has not yet heard of any producers having to spray for diamondback moth, although larvae are starting to show up and producers have had to seek control measures for other pests, such as grasshoppers or army worm, in some crops this year.

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“Flea beetles are common throughout the Prairies, everywhere we grow canola. We haven’t been able to predict in advance where they’re going to be the worst or which fields. We really lack the ability to predict this particular insect,” said Keith Gabert, an Alberta agronomy specialist with the Canola Council of Canada.

“A sheer number of flea beetles aren’t always the problem,” he said, adding the damage is most often in combination with a crop that isn’t doing well for various reasons. Those include a slow-growing crop because of drought, excessive trash on a field, pounding rain, crusting soil, and other types of pests.

That’s been in the case in Alberta with flea beetles where damage has so far gone hand-in-hand with damage caused by gophers, according to Alberta Agriculture’s latest crop report on Friday.

James Tansey, an entomologist with Saskatchewan Agriculture, said some flea beetles have been seen in that province.

“There’s a lot of discussion about flea beetles this year, but the damage level is not extraordinary. I would consider it to be on the moderate side,” he said, noting cooler-than-normal spring weather helped to delay the beetle’s development.

Crop damage created by the beetles has been in conjunction with cutworms, plus strong winds and dry topsoil conditions, according to Thursday’s crop report from Saskatchewan Agriculture.

In Manitoba, “there’s been a fair bit of canola that had to be sprayed or even reseeded because there have been flea beetles feeding,” according to provincial entomologist John Gavloski.

Though strong winds hampered spraying, canola has reached the point where it’s outgrowing the damage caused by the beetles, Manitoba Agriculture reported Tuesday.

In Saskatchewan, Tansey said there have been a good many reports of bertha armyworms, along with some reports of yellow cutworms.

“However, no reports of the usual suspects. No reports of western cutworm or redbacked cutworm, to date,” he said, noting those two could become an issue.

Damage from cutworms also required some fields in Manitoba to be replanted, Gavloski said. Traps for bertha armyworms were set up across the province’s growing areas as well.

As for diamondback moths, Gavloski said they are definitely present in Manitoba this year, but “they haven’t been much of an economic problem this far.”

In Saskatchewan, Tansey said traps have caught a significant number of adult diamondbacks in some regions. He suggested farmers keep an eye out for the moths, as they arrived early this spring.

“The direct correlation between catch numbers and resulting damage is pretty loose,” he cautioned.

Gabert said moth larvae in Alberta have been 200 to 300 per square metre. Farmers need to look for holes in the leaves of their crops as a warning sign. A few holes should mean the moths shouldn’t be much of a problem, but a lot of holes could mean trouble ahead.

— Glen Hallick reports for MarketsFarm from Winnipeg.

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Diamondback moth is the only one of the two to report threshold populations, according to both trap data and Manitoba Agriculture entomologist John Gavloski.

Eighty-eight out of the province’s 99 bertha armyworm traps sat at “low risk” as of July 18, with less than 300 adults moths caught in each trap. Five of the remaining six traps, all in western or central Manitoba, sit only a step higher on the province’s risk scale.

The numbers are slightly higher than the week before, when 93 or 99 traps were classified as “low risk.”

“Basically, what it means is scout your field,” Gavloski said in a July 11 Crop Talk webinar. “When numbers get into that range, there’s the possibility of some localized issues. Usually, if things stay in that range, we’re not looking at widespread issues.”

Cumulative trap counts must top 900 adults before the province considers it at “moderate risk.” All lower counts are labeled as “low” or “uncertain risk.”

Only Tilsten, Man., tipped past those levels, with a trap there counting 960 adults as of July 18.

Diamondback moth

Canola growers have marked threshold populations of diamondback moth, despite initially optimistic trap counts.

As of July 11, 64 of 91 traps set this year had returned less than 10 moths.

“That doesn’t mean don’t scout,” Gavloski said at the time.

Populations have since passed economic thresholds in some parts of the east and south Interlake.

A “moderate” population blew into the Interlake, also grazing the northern part of central Manitoba this year, Gavloski noted.

“Just like bertha armyworm, their major damage is really to the pods,” he added. “Now that we’re getting some rains, if you’ve got good soil moisture, canola can compensate very well for damage to flowers, to buds, leaf feeding. The one thing it can’t compensate well for is pod feeding.”

Gavloski encouraged producers to take that damage risk into account when deciding whether to spray.

The province is reminding producers to base management on the number of larvae shaken from plants, not counts from a sweep net, while producers may also want to keep their eyes on the weather forecast.

“Larvae can complete their development quickly in hot temperatures, so larval populations can change in a field quickly,” the last insect and disease report said.

Check the forecasts, but still scout

Trap counts may still largely be low, but the province is also warning producers that traps are used for regional forecasting, not management field to field.

“The data is really meant to get you looking in your fields to help you prioritize your monitoring,” Gavloski said. “You cannot make control decisions based on trap counts. The traps only collect male (bertha armyworm) moths. The females are the ones that lay the eggs and they do not always lay their eggs in the same fields traps are in. In fact, there’s been many cases where fields that had a trap and had high trap counts had extremely low larval levels.”

The entomologist made a similar point for diamondback moth.

Keep pollinators in mind

Gavloski has also warned producers to stay away from tank mixing insecticide unless a pest has reached economic thresholds.

Producers might cause an unintentional yield loss if that same insect management kills off pollinators, he said, since crops like canola have shown greater yield if there are pollinators present.

“It’s enough of a yield bump that if you really aren’t at an economic threshold, tank mixing in that insecticide likely will be a losing proposition,” he said. “If you’re at the threshold for bertha armyworm or diamondback moth or any of the other insects that time of year, then it may pay off.”

The entomologist suggests growers might expect a 10 to 15 per cent boost in yield from pollinators.

*UPDATE: Article updated to reflect a changes reported in diamondback moth numbers.

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There have been additional reports of suspected Phytophthora root rot in soybean. Growers in the western part of Manitoba are considering whether or not to make a fungicide application for FHB and sclerotinia based on the hot and dry conditions.

Phytophthora Root Rot in Soybean

Phytophthora root rot in soybean continues to be reported across Manitoba. Most of the cases are located in the Red River Valley, but there is also a suspected case in southwestern Manitoba. At this time of year, Phytophthora root rot is not always easily distinguishable from other root rots. It is recommended for suspected samples to be sent to the Crop Diagnostic Lab for identification. When sending samples for identification it is best to include plants that are not completely senesced or necrotic. Living tissue is required in order to isolate the pathogen from the infected plants.

Fusarium Head Blight and Sclerotinia Stem Rot Risk

Spring wheat and canola in western Manitoba are at or nearing the flowering period. This is the timing in which growers are deciding whether or not to spray a fungicide for Fusarium head blight (FHB) in wheat and sclerotinia in canola.

The FHB risk maps indicate a low risk for FHB infection at this point in time in western Manitoba. These maps are based on temperatures and precipitation in the last 7 days. The ideal temperatures for Fusarium infection are between 15 and 30 degrees Celsius. Daytime temperatures this week will not likely be conducive to FHB infection, but overtime temperatures coupled with humidity or precipitation may still lead to infection.

Manitoba Agriculture does not produce risk maps for Sclerotinia in canola. Growers in southern Manitoba may access the North Dakota State University Sclerotinia risk maps if they are interested. A good rule of thumb for Sclerotinia risk is the “pant leg” test. This refers to the moisture within the crop canopy at different times of the day based on the moisture collected on your pant legs after walking through the crop. If your pant legs are dry after walking through the crop at 10 am indicates that the chance of Sclerotinia infection is low. However, if you pant legs are still collecting moisture in the early afternoon there is a much higher risk of Sclerotinia infection.

The forecast for the next week will also play a role in the fungicide decision. Hot and dry conditions are not conducive to infection or symptom development. These conditions will also accelerate the flowering process. A shorter flowering period results in a shorter period of time where the crop is at the susceptible stage.

Thistle Caterpillars

Thistle caterpillar (Vanessa cardui) feed primarily on Canada thistles, but will also occasionally feed on crops like sunflowers, soybeans, and canola. They are generally at low enough levels in these crops that they are not regarded as economic pests. Adults of these caterpillars are commonly known as painted lady butterflies.

Larvae build a nest by producing a loose webbing, which at times may result in the leaves being folded or tied together. Frass produced by the larvae may become entrapped in the nest.

A suggested threshold in soybeans is 25 to 30 per cent defoliation prior to bloom; 20 per cent after bloom or pod set. Although individual plants may have some feeding, it would be very rare for a soybean field to on average have this level of defoliation from thistle caterpillar.

A suggested threshold in sunflowers is 25 per cent defoliation provided that most of the larvae are still under about 3 centimetres (1 1/4) inches) long. If the majority of larvae are fully grown, most of the feeding damage will have already occurred.

Diamondback Moth

Larval populations of diamondback moth have been approaching threshold levels in some canola fields in the southwest.  Generally canola can compensate well for diamondback moth feeding to buds and flowers, provided soil moisture is adequate. Some of the areas where the diamondback moth populations were high were also areas that had been drier. So in addition to the diamondback moth populations, consider the growing conditions and the plants abilities to compensate for bud and flower feeding. Heavy rainfall can be a mortality factor of eggs and early instars of diamondback moth. So in addition to providing moisture to help the plants compensate for feeding, with heavy rains larvae are very susceptible to drowning, and may be washed or wriggle to leaf axils or the ground where they drown in accumulated water.

If it is decided that an insecticide application is needed, and there is any flowering on the crop, you want to make sure you minimize risk to pollinators, which can help increase the yield of canola. Products are registered in canola that have little impact on pollinators. If a more broad spectrum insecticide is being used, such as one of the pyrethroids, make sure to spray as late in the day as possible to minimize harm to pollinators. A list of hazard ratings of insecticides to bees is available on page 621 of the Guide to Field Crop Protection.

To report observations on insects or plant pathogens that may be of interest or importance to farmers and agronomists in Manitoba, please send messages to:

• John Gavloski (entomologist) at John.Gavloski@gov.mb.ca (phone: 204-750-0594) or:
• Holly Derksen (plant pathologist) at Holly.Derksen@gov.mb.ca (phone: 204-750-4248)

Visit the insect pages on the Manitoba Agriculture website at www.gov.mb.ca.

Click here to view the complete Manitoba Insect & Disease Update on the Manitoba Agriculture website.

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The pesky feeders on crucifer crops, including canola, mustards and vegetables, have developed resistance to many insecticides as well as Bt (Bacillus thuringiensis), a soil bacteria that has been genetically engineered into corn and cotton to help control such pests.

The Cornell Chronicle newsletter cites recent research in which male diamondback moths genetically engineered with a gene that prevents females from reproducing can suppress populations and slow their evolution of resistance to Bt.

“We are at a crossroads right now with how we control pests, reduce pesticides and provide food for a growing world population in a changing climate,” said Anthony Shelton, professor of entomology at Cornell’s New York State Agricultural Experiment Station (NYSAES) in Geneva, New York, and co-author of the paper. “We need to put our heads together to solve these problems with new solutions.”

The genetically engineered moth was developed by the United Kingdom’s Oxitec Ltd.

A paper published in BMC Biology describes greenhouse trials where high numbers of the GE male moths were released into cages containing pest diamondback moths. Within a few generations, the engineered moths mating with the pest females led to a rapid decline of the pests.

The Chronicle said that in additional experiments, the researchers released low levels of the GE male moths in cages with Bt broccoli and pest moths. They discovered that the GE males kept pest populations in check and also delayed the buildup of resistance to the Bt broccoli.

“Adding the two biotechnologies together — engineered insects and Bt plants — demonstrates that you could both suppress the pest population and also decrease the number of Bt-resistant individuals in the population. The way forward in farming is responsible integrated pest management to improve available methods and to introduce new methods for safe and sustainable insect pest control,” Shelton said.

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Swathing or preharvest applications in the earliest-seeded spring cereal fields has started.

The majority of spring seeded crops are either grain-filling or podding, with some of the later seeded crops finishing up flowering.

• Click here for the Crop Weather Report for the week ending August 3

Southwest Region

In the Southwest Region, warmer temperatures are speeding crop maturity. A large storm system that moved from Pierson to Hamiota on July 27, resulted in varying amounts of precipitation; rainfall amounts ranged from 25 to 125 mm across the region. The storm system also resulted in an EF2 tornado that tracked from south of Tilston to north of Virden, spending approximately 3 hours on the ground. Crops such as corn, sunflower and oats were severely lodged in the path of the tornado, whereas areas further from the path location also sustained heavy crop lodging. Some hail damage in Souris, Wawanesa and Minto areas was reported as well.

Most winter cereals are close to physiological maturity. Low fusarium head blight levels in winter wheat and low ergot levels in fall rye continue to be reported. Initial winter wheat harvest has begun in the Brandon and eastern areas of the region, with average yields reported.

Canola crops responded favourably to the cooler temperatures and recent rainfall. The earliest canola fields are at the pod filling stage of development, while most reseeded fields are finishing flowering. Some early seeded barley, wheat and oats are also nearing maturity, whereas late seeded cereals are still in hard dough stage.

Flax fields are coming out of flower and are experiencing some lodging due to the recent heavy thundershowers. Field peas are starting to dry down. Some pea harvest has begun in the Rivers area with average to slightly above average yields reported. Increased levels of mycosphaerella are being reported in later seeded field peas as a result of the cooler and wetter conditions.

Corn is in full tassel. Sunflowers entered early to mid-flower stages. Lygus bugs are affecting some sunflower stands. Soybeans continue to respond well to the excellent growing conditions with many crops now advanced into the late R3 (pod initiation) to R4 (full pod) stage of development.

Hay and pasture conditions across the Southwest Region continue to be variable. First cut hay is complete and native hay is being harvested. Generally, yields are 50 to 75 per cent of average. Second cut growth is advancing well where first cut was taken early and there is adequate moisture. Harvest of greenfeed cereals are beginning. Dugout levels remain steady at 80 per cent full.

Northwest Region

A major weather system moving through most of the Northwest Region over the past week resulted in 38 to 51 mm of rain reported for most of the area, and 101 to 152 mm reported in the McCreary and Ste Amelie areas. Daytime temperatures were warm with brisk to strong winds reported. Soil moisture conditions improved over the past week and are adequate in most parts of the Northwest Region.

Crops in the Northwest Region are reported to range from good to poor condition. Some of the heavier crops lodged as a result of the heavy rains and winds experienced last week, particularly canola.

Approximately 10 per cent of the winter wheat crop is in the dough stage of development and 90 per cent is mature. About 10 per cent of the spring wheat crop is at the milk stage of growth with the remaining 90 per cent in the dough stage. Some rye and barley has been harvested in the southern part of the region. Preharvest glyphosate applications have begun.

Canola improved significantly over the week as the crop continues to develop rapidly. Approximately 50 per cent of the canola crop is at some stage of flowering while about 50 per cent is podded. Approximately 90 per cent of the corn crop is in the V6 to V13 stage of growth and 10 per cent is tasseling. For soybeans, 30 per cent of the crop is flowering with 70 per cent podded. About 30 per cent of the flax crop is flowering with the remaining 70 per cent at the boll stage of growth.

Crop insect pest activity throughout the region has been low, and producers continue to monitor crops closely for any signs of insect pest activity.

It is estimated that 75 per cent of first cut hay is complete with below average yields in most parts of the Northwest Region. Cutting of native hay has begun. Harvesting of annual forages for greenfeed and silage is also underway. Pastures are in average to good condition.

Central Region

Warm and humid weather conditions continued in the early week, allowed for rapid crop growth in the Central Region. Temperatures moderated mid-week. Most areas have adequate moisture and heavy morning dews are common. Unsettled conditions remain and showers and thundershowers continue. Rainfall amounts varied from a few millimeters to as much as 35 mm. There are reports of damaging hail in the Letellier, Dominion City and Ridgeville areas. Hail damage resulted in defoliation of soybean plants, pod loss and shattering in canola, and flattened sunflowers; fields are being assessed. Rain and winds resulted in many lodged cereal crops.

Cereal crops throughout the region look good and some of the lodged cereal fields have recovered to a certain degree. However, harvest will be a challenge in many spring wheat fields and yield loss of some degree is expected. Fusarium head blight levels appear to be much lower than last year in both winter and spring wheat.

Harvest of winter wheat and fall rye has begun. Early yields of winter wheat are reported in the 60 to 85 bu/ac range. Some spring wheat is harvested; no yield reports to date. Harvest management applications continue in spring wheat fields.

There is a wide range in canola development due to the varied seeding dates. Reseeded canola fields from the late May frost are almost done flowering. Some canola fields have been opened up with a swathed round or two; the odd field has been swathed. Many fields are lodged due to heavy winds.

Sunflowers are flowering. Monitoring continues for insects, and staging is being done for fungicide application. Sunflower beetle numbers are low. Corn is growing rapidly. Fields are silking with cobs are starting to form.

Soybeans continue to flower and form pods. Some fields are showing increasing damage due to excess moisture and subsequent root rots. Some fungicide applications are being made. Reports of soybean aphids are becoming more common, but are well below economic threshold to date.

Edible beans are flowering, and fungicide applications continue. Environmental conditions are conducive for white mould. Bacterial blight is reported in cranberry and kidney types; other varieties can also be affected. With recent heavy rains some fields are showing stress symptoms of yellowing. Overall most fields look good. Pea fields are mostly done flowering and the majority podded.

Diamondback moth and bertha armyworm trap counts are average to low for the season indicating a low to moderate risk of damage from these canola pests. Lygus bugs are found in canola fields, but numbers are below threshold levels in most cases. Insecticide applications have taken place where sunflower head insect populations have warranted. Wild oat plants are emerging above the crops in patches, as are other later emerging weeds in thinner areas of fields. Weed growth is noticeable in lodged cereal fields.

Hay harvest continues in the Central Region but has been difficult with the high humidity and recent rains. Greenfeed is being cut for forage. Hay yields are expected to be near normal and at quantities sufficient for wintering supplies. Pastures are lush with abundant rain and warmer temperatures. Alfalfa weevil damage is visible in some of the alfalfa/grass fields.

Eastern Region

In the Eastern Region, the weather during the previous week was highly variable. Cool temperatures with drizzle alternated with sunny weather or significant rainfall that sometimes included isolated severe weather events. Rainfall accumulations ranged from trace amounts to over 30 mm. Some isolated, severe hailstorms occurred in southern districts. Across the Eastern Region, fields continue to show evidence of standing water and areas where crop is drowned out and is more prevalent in central and southern districts. Soil moisture conditions on crop land are rated as adequate to surplus.

Spring cereal crops are in the soft to hard dough growth stages. Winter wheat is mature and some harvesting and swathing started over the weekend. Canola is pod filling. Soybeans range from R3 to R5. Sunflowers are in R5 growth stages with corn silking. Damage from sclerotinia is noted in canola fields that were not sprayed with fungicide at flowering.

Across the region, the majority of hay and pasture lands are in good condition. Haying was back to full swing with 30 to 50 per cent of the feed being put up. Second cut alfalfa is 50 per cent completed. For first cut hay, it is estimated that 25 per cent is standing, 15 per cent is cut and 60 per cent is baled or put up as silage. For second cut hay, it is estimated that 50 per cent is standing, 20 per cent is cut and 30 per cent is baled or put up as silage. Quality is rated as good. Availability of livestock water is adequate.

Interlake Region

Precipitation and cooler temperatures were experienced in the Interlake Region last week. Rainfall amounts varied throughout the region. Moosehorn received the most precipitation with just over 40 mm, Selkirk 30 mm, and the rest of the region amounts between 10 to 20 mm of rainfall. Cool temperatures moved in with daytime highs between 20 to 25 C and night time temperatures dipping below 10 C.

Harvesting of winter wheat and barley has begun in the Interlake Region. Winter wheat crops are coming in with reports of yields in the 65 to 70 bu/ac range with little to no fusarium damaged kernels in samples. Barley yields are ranging from 70 to 80 bu/ac with good quality. Spring wheat and oats continue to mature with some spring wheat possibly receiving preharvest applications towards the end of the week, into the beginning of next week. Soybeans continue to flower and fill pods, corn is at the tassel stage and sunflowers are flowering.

Canola fields are nearly finished flowering with some early seeded fields starting to show coloured seeds in the bottom pods. Lygus bugs in canola are being monitored as populations are approaching thresholds in parts of the North Interlake. Some spraying occurring in alfalfa seed fields for weevils and lygus bugs. Timothy and other grass seed fields are being swathed with some fields going to be combined towards the end of the week.

Clearer weather allowed some much needed progress with haying this past week. Cereals have started to be cut and ensiled. Pastures are holding up quite well with the numerous showers during the past four weeks. Some second cut alfalfa has been taken with good yields; in some cases second cut yielded higher than first cut due to spring frosts and somewhat drier conditions in June. Availability of water for livestock is adequate.

The post Manitoba Crop Report and Crop Weather report: Issue 14 appeared first on Manitoba Co-operator.

In what they said could be a pesticide-free and environmentally friendly way to control insect pests, the scientists, from the Oxford University spinout company Oxitec, developed diamondback moths with a “self-limiting gene” which dramatically reduced populations in greenhouse trials.

The self-limiting gene technique has already been tested against dengue fever-carrying mosquitoes, cutting their populations by over 90 per cent in trials in Brazil, Panama and the Cayman Islands.

“This research is opening new doors for the future of farming with pest control methods that are non-toxic and pesticide free,” said Neil Morrison, an Oxitec research scientist who led the study.

According to the researchers, whose work was published in the journal BioMed Central Biology, the struggle with diamondback moths in cruciferous vegetable production costs farmers around the world up to $5 billion a year.

Tony Shelton, an entomology professor at Cornell University in the United States who worked with Morrison, said neither conventional nor organic pesticides can control the moths.

“Diamondback is a serious problem for farmers in New York state and around the world — anywhere cruciferous vegetables and field crops are grown,” he said. “These moths invade and attack the crops, and they are developing resistance to insecticides, so we urgently need new tools to better control them.”

The researchers genetically engineered male moths that can mate just as well as the non-GM insects, but only produce male offspring. In greenhouse trials, releasing the GM moths into the population resulted in a crash in moth numbers within eight weeks.

The scientists said that unlike insecticides, which can affect a range of insects including bees, the genetic modification approach is purely species specific, only affecting the targeted pest. The self-limiting gene is also non-toxic, so birds or other animals eating the moths get no harmful effects.

Independent experts welcomed Oxitec’s success.

“If the results can be replicated in the field then it would represent a big step forward in eco-friendly ways of controlling insect disease and improving food production,” said Johnjoe McFadden, a professor of molecular genetics at Britain’s University of Surrey.

Shelton now plans followup studies to test the Oxitec moths under harsher, outdoor conditions in upstate New York.

These studies, already approved by the U.S. Department of Agriculture, will include field cage tests this summer, he said, with plans for small-scale field releases in future.

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