Pests
As swede midge populations continue to rise in Quebec, canola growers are looking for better ways to manage the pest. Entomologist Geneviève Labrie is leading a two-year research project to help advance integrated management strategies for swede midge.
Published in Insect Pests
Two of the most commonly used insecticides around the world are imidacloprid (neonicotinoid) and chlorpyrifos (organophosphate). In a new paper, published in the journal Scientific Reports, they have been found to be toxic to seed-eating songbirds, even affecting their migration. 

University of Saskatchewan biology professor Christy Morrissey stated in a press release, “Studies on the risks of neonicotinoids have often focused on bees that have been experiencing population declines. However, it is not just bees that are being affected by these insecticides.” | READ MORE
Published in Insecticides
Bees can provide a helping hand to farmers with a new green technology to fight against major fungal diseases such as sunflower head rot and grey mould.
Published in Diseases
Agriculture Canada scientist Jeff Skevington, who works with the Canadian National Collection of Insects, says the country has lost a significant amount of its insect biodiversity in recent years based on the results of annual collection samples.

That means a lot of the insects at the bottom of our food chain are dying out, which could have an unexpected, but noticeable impact on the lives of humans. READ MORE
Published in Corporate News
Earlier this summer (Week 14), true armyworm, Lepidoptera: Noctuidae: Mythimna unipuncta, was reported on the lower west coast and a summary was provided by Tracy Hueppelsheuser from the B.C. Ministry of Agriculture.

Hueppeisheuser kindly provided an update to the situation.... The initial true armyworm damage reported earlier did not relent and a second generation of voracious larvae continued to cause damage in late August through to late September in southwestern British Columbia. READ MORE
Published in Insect Pests
Cereal breeders continue to focus on improved yields, developing varieties that stand up to the pest and disease challenges producers face across the Prairies. Seed companies have supplied Top Crop Manager with the following information on new cereal varieties for 2018.
Published in Cereals
When it comes to fighting Fusarium graminearum, our crops may soon have some new tiny but powerful allies. Research by Manish Raizada at the University of Guelph is providing the foundation for commercializing some anti-Fusarium bacteria as biocontrol products. As well, a student in his lab discovered an amazing mechanism that a bacterial strain called M6 uses to stop the fungus dead in its tracks.
Published in Diseases
OMAFRA has conducted a soft launch of the new online version of the Inspection of Soil Pest Assessment Forms (PARS) for the purchase of neonicotinoid treated corn and soybean seeds from Class 12 Vendors.

The online version allows a producer or professional pest advisor to complete the form online, and email it directly to the Class 12 Vendor of choice.

The vendor will be advised of the request and when accepted, a copy will automatically be sent to OMAFRA thus alleviating the need for the vendor to submit these online forms to OMAFRA by October 31st of each year.

In addition, this version will assist the producer or professional pest advisor to complete and attach the required sketches via OMAFRA's AgMaps mapping tool.

For more information, click here.
Published in Soil
Domesticating plants to grow as crops can turn out to be a double-edged scythe.

On one hand, selecting specific desirable traits, such as high yields, can increase crop productivity. But other important traits, like resistance to pests, can be lost. That can make crops vulnerable to different stresses, such as diseases and pests, or the effects of climate change.

To reduce these vulnerabilities, researchers often turn to the wild relatives of crops. These wild relatives continue to evolve in nature, often under adverse conditions. They possess several useful genes for desirable traits. These traits include high levels of resistance to diseases and tolerance to environmental stresses.

In a new study, scientists report significant strides in transferring disease- and stress-resistance traits from wild relatives of several legumes to their domesticated varieties. This research was conducted at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) in Patancheru, India.

Legumes, such as chickpea, pigeonpea, and groundnut, are among the few crops that grow well in the scant rainfall and marginal soils of the semi-arid tropics. But they are facing significant challenges, says Shivali Sharma, lead author.

“Legume crops are hit hard by diseases, insect-pests, drought, heat stress, and salinity,” says Sharma. “Also, semi-arid regions are highly vulnerable to climate change.” These factors limit legume crops.

There are several wild relatives of these crops that are resistant to pests and diseases. “There is an urgent need to find and introduce these useful genes from wild relatives into crop cultivars,” says Sharma. That would improve the resilience of domestic legume varieties and sustain agriculture in these regions.

It can be highly challenging – and often impossible – to directly breed domesticated crops with their wild relatives. For example, of the eight wild annual species of chickpea, only one is readily crossable with cultivated chickpea and yields fertile offspring.

Similarly, wild varieties of groundnut are resistant to fungal infections. But direct crossing of wild and domesticated groundnut is challenging because of differences in how the DNA in their cells is packaged. Additionally, these species do not cross well with cultivars.

Most wild varieties of groundnut are diploid: their DNA is organized in two sets of chromosomes per cell, much like in humans. During reproduction, one set comes from the male parent and the other set from the female parent.

Domesticated groundnut plants, on the other hand, are tetraploid. Their cells contain four sets of chromosomes. The sets of chromosomes in each cell, called ploidy, makes it difficult to directly interbreed wild and domestic varieties of groundnut.

“It takes a lot of time and resources to overcome challenges like these,” says Sharma. “That often makes breeders reluctant to directly use wild species in breeding programs.”

Pre-breeding programs, such as the one at ICRISAT, invest their time and skill in the wild crop relatives. Sharma and her colleagues bred wild groundnut varieties whose cells have four sets of chromosomes. Then they identified which of these tetraploid wild varieties were also resistant to fungal infections. These were then crossed with cultivated groundnut varieties to develop new breeding lines with good resistance and yields. Plant breeders can now directly cross these fungal-resistant lines with domesticated groundnut to create new varieties.

“Crop wild relatives are the reservoir of many useful genes and traits,” says Sharma. “It is our responsibility to use this hidden treasure for future generations.”

It’s especially important in the context of legumes because they provide a bevy of benefits. For instance, bacteria in their root nodules pull in valuable atmospheric nitrogen. That increases soil fertility and reduces the need for fertilizers.

Legumes are also vital for food security in the semi-arid tropics and other parts of the world. They are an important source of protein and micronutrients. Combined with cereals, they are a sustaining diet for people across the world.

And “pre-breeding programs are the first step to improve the nutrition and resilience of modern legume varieties,” says Sharma.

Read more about this research in Crop Science.
Published in Other Crops
A group of international scientists is meeting in the national capital to try to convince parliamentarians there is no longer any doubt that common agricultural pesticides are proving toxic to ordinary honey bees.

Jean-Marc Bonmatin of the French National Centre for Scientific Research, represents a task force on pesticides within the International Union for Conservation of Nature, which in 2015 released a comprehensive review of more than 1,100 peer-reviewed research studies on neonicotinoids. READ MORE
Published in Insecticides
Armyworms have arrived in the Fraser Valley. Common armyworm (or true armyworm) is the larval stage of the moth Mythimna unipuncta.

The worms were first discovered in B.C. on Vancouver Island in the summer, but in recent weeks some farmers have found them in the Fraser Valley from Delta to Chilliwack. READ MORE
Published in Insect Pests
Harvest of cereal crops is nearly complete for this crop year and grain is in storage bins, waiting for delivery. While your grain is in storage, keep these methods in mind to protect its quality from insect infestations and mould.

Keep grain cool. Check your temperature probes every two weeks while grain is in storage. For best results, the temperature of grain should uniform and be less than 15°C. Aerating or turning grain helps keep grain cool and dry. Hot spots in grain may be indicators of the presence of insects.

Monitor moisture levels. Keep your grain at the appropriate moisture content to reduce the risk of spoilage. Moisture levels should be checked every two weeks.

Spot and identify insects. When you check grain moisture and temperature, take samples from the core of your grain to monitor for insect populations. Also check the top of the grain in the bin – this is where heat and moisture collect and insects may find this very attractive. If you find insects, determine what type they are to find the best control method.

Watch out for mould. Under warm, moist conditions, moulds can grow quickly and some fungi may produce poisonous mycotoxins, such as ochratoxin A. Mould may not be visible in dark grain bins or may form inside the grain bulk. A musty smell or grain clumping or caking may be signs of mould.

Contact the Canadian Grain Commission's Infestation Control and Sanitation Officer for further assistance.

Monitor stored grain regularly for hot spots and insect populations:
  • insects are likely to be found in pockets of warm or moist grain
  • sample the grain from the core at a depth of 30 to 50 centimetres (12 to 18 inches) from the surface
  • sieve the samples or examine small portions carefully
  • stored product insects are typically very small beetles (less than 3 millimetres or 1/8 inch) that may not be moving, so a magnifying glass can be helpful
Identify insects in your grain to determine the right control method
  • insects in your grain could be grain feeders, fungal feeders, or predators of these insects
  • for advice on controlling grain-feeding insects, visit the Canadian Grain Commission's website
For further information: Brent Elliott, Infestation Control and Sanitation Officer, Canadian Grain Commission, 204-983-3790, This e-mail address is being protected from spambots. You need JavaScript enabled to view it
Published in Storage
Parts of southwestern Ontario remain dry, while eastern Ontario continues to have frequent rainfall and saturated soils in many areas. While yields have been good, making dry hay continues to be a struggle for many growers under the later conditions.

Winter wheat harvest has continued this past week in eastern Ontario. Most fields in the area have yielded between 70 to 80 bushels per acre. Quality has generally been better than expected. Spring cereal harvest has just begun on a small number of acres that were able to be planted early this spring.

Insects
Soybean Aphid numbers are generally low, but increasing in some areas in eastern Ontario. Soybean growers should be scouting. Apply foliar insecticide when threshold of 250 aphids per plant with increasing populations has been reached in the R1–R5 stage of soybeans. If aphid populations do not appear to be on the increase above 250 per plant, do not apply insecticide, as it will kill off the beneficial insects that are keeping the aphid population in check. Aphids are then likely to increase quickly in the absence of their predators and could easily reach threshold.

For further information on scouting techniques, thresholds and management options, see OMAFRA Publication 812, Field Crop Protection Guide.

Potato Leafhopper (PLH) continued to be a problem in many alfalfa stands particularly in eastern Ontario. Sweeps collected are showing at and above threshold numbers in many fields that have not been treated. Although PLH are rarely a problem in soybeans they can cause significant yield and quality losses in alfalfa and edible bean stands. New seedling alfalfa stands are particularly vulnerable as the PHL damage can weaken the new seedling alfalfa plant, making them more susceptible to stresses like winterkill.

Economic losses occur before plant symptoms develop, so it is important to identify the presence of large leafhopper populations before the damage occurs. Scouting with a sweep net will help you determine whether early harvest or spraying is needed. Scout at intervals of 5 to 7 days. To determine the number of leafhoppers, including adults and nymphs, take 10 sweeps and divide the number of insect captured by 10. Do this in 5 representative areas of the field and note the height of the alfalfa. Recommended action thresholds are listed in Table 1 below:

Table 1: Thresholds for Potato Leafhoppers in Alfalfa
Stem Height      # of PLH per sweep
9 cm (3.5 in.)     0.2 adults
15 cm (6 in.)      0.5 adults
25 cm (10 in.)    1.0 adults or nymph
36 cm (14 in.)    2.0 adults or nymph

It is important to make decisions to control PLH based on these threshold numbers as spraying insecticides on alfalfa will also kill beneficial insects, the natural enemies of PLH and alfalfa weevil.

Foliar insecticide options are available in Publication 812, Field Crop Protection Guide here.

Western Bean Cutworm (WBC) trap counts are still increasing in most counties north and east of Perth and into eastern Ontario. That means that WBC moth flight has not yet peaked in those areas. This is important because this also means that we have not reached peak egg laying in those areas and that there are a lot of moths flying around looking for somewhere to lay their eggs. Late planted corn fields that are still in the early pollination stages (i.e. silks have not dried down yet) and edible beans are still at risk.

For late planted corn fields, most of what you need to know about scouting and management has already been posted in a previous post here.

For edible beans, it is not as straight forward. Unlike in corn, WBC are nearly impossible to find in dry bean fields until pod feeding begins. Pheromone traps can still help indicate which fields are at greater risk though. Traps at dry bean fields that capture an accumulation of 50 or more moths per trap are likely at greater risk and require scouting for pod feeding.

Pod feeding is expected to begin 10 to 20 days after peak moth flight has occurred, as indicated when trap counts begin to decline after weeks of steady increase. Prior to pods being present on the plants, scouting for egg masses in adjacent cornfields can also help determine what the local WBC populations are like. If any of the corn fields in the immediate area are past early tasseling, the dry bean fields will be more attractive for the moths. If an adjacent corn field reached the corn egg mass threshold and required spraying, the dry bean field is also likely at risk.

Once pods are present, scout 100 plants (10 plants in 10 areas of the field). Look for signs of early surface feeding or holes going directly into the pod. If pod feeding is easily found, a spray application is necessary. Control is still very effective when done as soon as pod feeding is found. WBC exit and enter new pods each night, so insecticides still work at controlling the larvae, as long as the pods are present during the application so that there is residue left on the pod surface.

Spraying too early when pods are not present on the plants will not protect the crop from damage. Spraying too late, when pod feeding has been taking place for some time will not reduce the risk of seed damage and pod disease incidence. The key is to protect the plants when the larvae are feeding on the pods.

Foliar insecticide options are available in Publication 812, Field Crop Protection Guide.
Published in Corporate News
A groundbreaking new method for controlling flea beetle, the pest that causes at least $300 million in damage in North American canola every year, may hit growers’ fields early in the next decade.

RNA interference, or RNAi – a process by which RNA molecules “silence” genes targeted as threats – has already been harnessed by public and private research and development programs against several agricultural pests, including Colorado potato beetle (CPB) and corn rootworm.

According to Jim Baum, Monsanto’s insect control lead in chemistry, the use of RNAi technology against flea beetle “represents a sizable opportunity and need” for canola growers in the U.S. and Canada who have seen incomplete protection from neonicotinoid insecticides and other chemical products in recent years.

Monsanto began work on an RNAi-based product for flea beetle control several years ago, Baum says, as part of a suite of RNAi projects aimed at controlling agricultural pests, including corn rootworm and CPB.

Put simply, RNAi for flea beetle control works by “tricking” the beetle’s natural immune system to self-destruct. Beetles are fed double-stranded RNA (dsRNA) molecules that “turn down” expression of a critical gene in the flea beetle midgut, killing exposed insects within five days.

There are two possible delivery methods for RNAi-based pest control in agriculture: plants can be genetically engineered to express dsRNA in their leaves, or dsRNA can be applied externally to plants as a topical spray. Monsanto has worked with both methods; its corn rootworm product is transgenic.

But the company’s flea beetle project is currently focused on the development of a foliar insecticide that can be applied using its patented BioDirect platform.

Monsanto advanced its CPB BioDirect product to Stage 2 in 2015, and Baum says the company’s experience in RNAi for CPB control has streamlined its approach to new RNAi products.

The company has already run lab bioassays monitoring mortality in insects fed various dsRNAs, as well as seedling assays in which a set number of beetles are exposed to canola seedlings treated with dsRNA at a prescribed field rate.

Last year, Baum says, Monsanto ran successful field trials for its flea beetle RNAi project, and this year the number of trials more than doubled. (The company could not comment on the location of the field trials).

Next up, Monsanto will be analyzing effectiveness of various agronomic practices — basically, what works best in terms of rates and application timing, and how the product will work in combination with other products.

“Compared to previously approved products’ timelines, we’re being conservative with this one, recognizing that topical is a new application of the technology,” Baum says. “But if the project is successful, we’re projecting commercialization sometime on the early side of the next decade.”

Farmer and consumer outreach
Though RNAi-based insect control products won’t reach farmers’ fields for several years, they need to know what’s coming, and farmer and consumer outreach will be more important than ever for companies looking to commercialize the technology.

This is the view of Curtis Rempel, vice-president of crop production for the Canola Council of Canada.

“RNAi provides a tool or a technology that takes us outside of the traditional chemistry realm, so it has the potential for much improved environmental outcomes, but along with new technologies come a new set of regulatory and efficacy evaluations,” he says.

Just how safe is RNAi? According to Baum, RNAi has a built-in specificity that means once dsRNA is targeted to a specific insect pest, even closely related pest species are not harmed when they ingest it. “It’s hard to imagine a chemical insecticide, even Bt, that would be as specific as this RNAi product we’re talking about here,” he says.

Rempel agrees but believes farmers and consumers alike need to feel that regulators and scientists have had the opportunity to evaluate RNAi technologies in terms of environmental and societal norms.

Next year, the Canola Council hopes to include discussions around RNAi in its annual Canola Discovery Forum, and Rempel says the organization is working on developing “supporting material” to help communicate the role of RNAi in pest control to stakeholders – although he is quick to point out that communications outreach about RNAi requires the collaboration of all stakeholders.

In Rempel’s estimate, only 10 per cent of farmers are familiar with RNAi and aware of projects in the pipeline, even though they are the ones who will benefit most from its use.

But consumers shouldn’t be neglected either. After all, it’s consumers who implicitly afford farmers the “social license” to use technologies like RNAi, and they are the ones who will need to be assured of the products’ safety.

“I think we have an opportunity to do a good job of looking at the questions we’re asking, reviewing regulatory procedures and communicating these to the layperson,” Rempel says.

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Published in Insect Pests
Western bean cutworm (WBC) continues to be a concern for pollinating corn in areas with high trap counts. Peak moth flight has occurred in counties in the southwest but counties in Central and Eastern Ontario have not reached peak yet. Moths will now be looking for late planted corn that is still in the early tasseling stages or will focus on edible beans. Focus scouting efforts in those corn fields that do not have dried silks yet. Edible bean growers need to scout for pod feeding once pods are present. Edible bean fields that are adjacent to corn fields that reached WBC eggmass threshold this year are likely also at risk. It is best to control fields as soon as pod feeding is observed. The larvae are exposed to the insecticide when they make holes in the pods to get to the seed. For additional information on WBC thresholds as well as optimal scouting and insecticide application timing, click here. Information on product choices is available in the OMAFRA Field Crop Protection Guide.

Post Wheat Harvest Manure Application
For livestock producers and those using organic amendments, the post wheat harvest season is an excellent opportunity to apply manure for nutrients and organic matter. Spreading workload, reduced compaction and reduced risk of environmental losses from runoff and erosion, as well as the opportunity to combine the benefits of feeding cover crops with manure, are all benefits of manure applied during the growing season.

Where manure or other organic amendments are applied to fields it is important to take a sample for analysis to help determine available nutrients and potential commercial fertilizer savings. Along with analysis for N, P and K in manure, additional tests will help determine nutrient availability. Testing for sulphur will provide an indication of elemental sulphur content which is released to a crop similar to organic nitrogen and can provide all or some of the sulphur needs, especially for wheat and forage crops. Testing for C:N (carbon to nitrogen) ratio for solid manure and amendments will help indicate if additional commercial N will be required for a corn crop. C:N ratios below 20:1 will have adequate nitrogen to help with the breakdown of carbon. Materials with C:N ratios over 30:1 (especially for spring applied materials) should determine with pre-side dress N test if addition N will be required. With liquid materials, testing the pH will help determine the potential for rapid ammonium N loss where manure is not injected or immediately incorporated. Liquid manure with high NH4-N levels combined with high pH (above 7.8) will lose the majority of the quickly available nitrogen in the first 24 hours, especially when combined with warm dry soils and/or high winds over bare soils.

Often there is too little credit given to the nitrogen supplied by fall-applied manure. A general guideline with fall applied manure is to credit half the total nitrogen from the analysis. Cattle manure with heavy bedding and/or amendments with high carbon to nitrogen (C:N) ratio will have lower (30 to 40 per cent) nitrogen credit while broiler poultry manure will have higher N credits (50 – 60 per cent). Mild winter conditions will increase available N from solid manure but can reduce nitrogen contribution from liquid manure where ammonium N (NH4-N) is higher. An early warm period in spring also increases nitrogen contribution from manure to a crop, while a cool wet spring will slow down nutrient release; not able to meet the N needs of a rapid growing corn crop during the period ahead of pollination. Slow release nitrogen from manure will contribute to yield after pollination, especially in areas where frequent and heavy rain may have resulted in denitrification or leaching of commercial N sources. Tissue tests of fields with evidence of some N deficiency on lower corn leaves reveal that levels are still within the normal range. Where manure or other amendments were applied there should be adequate nitrogen to meet remaining crop needs.
Published in Harvesting
Swede midge first appeared in canola in Ontario in 2003, and recent extreme populations in northeastern Ontario resulted in the Ontario Canola Growers’ Association (OCGA) strongly recommending in 2015 that producers avoid growing canola for three years across the New Liskeard area in an attempt to suppress swede midge populations.
Published in Insect Pests
It's time to scout for western bean cutworm, especially as moth flight activity climbs in Ontario. Although there are no significant reports of soybean aphids, growers are still urged to scout by OMAFRA. Winter wheat harvest is underway, while growers are reminded to plant cover crops after wheat harvest to minimize the amount of annual weeds going to seed. 

Cereals
Winter wheat harvest has begun throughout southwest Ontario but intermittent rainfall has caused delays. Some farmers in Essex County have finished harvest and initial word is that the quality and yield of the crop has been good. Harvest progress is likely seven to 10 days behind what was observed in 2016, but comparable to the 2015 season.

Post-harvest weed management
A significant amount of annual weed seeds can be produced and dispersed after wheat harvest if the ground is left fallow. In some years, annual weed seed can mature in as little as four weeks after harvest. Planting a cover crop (i.e. oats) after wheat harvest can do a nice job of minimizing the amount of annual weeds going to seed and then allows for an opportunity in the fall to terminate the cover crop and deal with perennial weeds at the same time. If it is not desirable to plant a cover crop, shallow tillage can also reduce the amount of weeds setting seed and will allow the perennial weeds to re-grow so that they can be managed in the fall.

If red clover was inter-seeded into the wheat crop there are a couple of ways that you can knock back annual weed growth so that you can let the clover grow as much as possible and maximize its nitrogen credit. The tried and true method, but most labour intensive, is to “clip” or trim the top of the red clover which will ‘chop off’ the weed seed heads at the same time. More recently OMAFRA and the University of Guelph have experimented with the application of MCPA as a way to manage broadleaf weeds in a red clover cover crop. There are three key learnings from this work:

1) The ester formulation of MCPA causes significantly less plant damage than the amine formulation.
2) Red clover biomass is initially stunted during the first week after application but does recover within two to three weeks.
3) Targeting broadleaf weeds when they are smaller will result in better control. If annual grassy weeds are predominant then the application of MCPA Ester will be insufficient and clipping is a better option to minimize weed seed dispersal.

Corn
Western bean cutworm moths have been found in traps throughout southwestern Ontario. An interactive map of trapping numbers can be found at cornpest.ca. Moth flight activity has indicated that it’s a good time to scout fields for egg masses which have become visible in several fields with some approaching or are above the action threshold of five egg mass per 100 corn plants. Peak flight has not occurred yet in Ontario so to provide the most protection with one application, time the application once threshold has been reached and when there is an ear developing with fresh silks. Download the pestmanager app (pestmanager.ca) to have access to management options for this pest.

Soybeans
There have been no significant reports of soybean aphids, although regular scouting should be done from now until the R6 (full seed) stage of soybean to minimize any yield loss with this pest. The action threshold is 250 aphids per plant, and with actively increasing populations on 80 per cent of those plants when the crop is in the R1 stage until end of R5 stage.

Edible beans
Monitor traps to determine western bean cutworm (WBC) presence in your area and be aware of what WBC infestations are like in adjacent corn fields. Bean fields should be scouted as soon as a pod is developing to spot any pod feeding by WBC. Refer to the moth trapping maps at cornpest.ca to identify areas where moths are actively being trapped.
Published in Corporate News
New PowerCore from Dow AgroSciences offers control of a number of key, above-ground corn insect pests Canadian corn growers battle, including black cutworm.
Published in Corporate News
Cereals
Current weather conditions are ideal for fusarium head blight development in winter wheat. Many wheat fields in Southwestern Ontario have applied a T3 fungicide to reduce their risk particularly if they are growing a FHB susceptible variety. T3 fungicide applications further east will begin this week and continuing into next week for Eastern Ontario. A number of fields saw increased stripe rust pressure over the weekend. Growers with fields that were a few days away from a T3 application opted to wait and spray for both stripe rust and fusarium at the T3 timing. Some fields received an early heading fungicide application if they were a week or more away from a T3 fungicide application and growing a stripe rust susceptible variety to reduce the impact from stripe rust. Those fields will then receive a second fungicide application at pollination for protection against fusarium if needed. There have been reports of leaf tip necrosis starting on the flag leaf and moving down in fields. This leaf tip necrosis is likely associated with a specific or group of disease resistant genes and is the plant’s response to the presence of disease such as stripe rust. The yield impact from this is minimal.

Early spring cereal fields are at tillering and continue to look good. All weed control applications should be wrapping up shortly.

Corn
Corn planting is essentially now complete. With the exception of corn silage or some growers in long season regions, most unplanted fields will now likely be switched to soybeans. If corn herbicides have been applied but corn could not be planted, work with your herbicide provider to determine next best cropping steps. Overall corn is progressing well with a large amount of crop at the 2-3 leaf growth stage, with early planted corn beyond that. Minimal corn replants have been reported to date. Some sidedressing is now underway. There have been reports of black cutworm and slug feeding in a number of fields as a result of delayed crop planting and emergence and cool, wet weather conditions. There have also been reports of corn turning purple or white as a result of stress but those fields are expected to grow out of this.

OMAFRA Field Crop staff began tracking soil nitrate levels at a number of sites across the province the first week of May. Initial results suggest that soil nitrate levels are lower this year compared to previous years. Conventional PSNT timing sampling is being completed this week. Results will be posted at Weathercentral.ca under “Corn – GFO Nitrogen Research” as they are made available.

Soybeans
Soybean planting is 80 per cent completed across the province with some areas further behind compared to previous years due to significant rainfall this spring. The crop ranges from the hook stage to unifoliate growth stage. There continues to be weed challenges in a number of fields that did not receive a pre-plant burndown. Weed control during the early stages of soybean growth is critical. When making herbicide spray decisions pay attention to the growth stage of the weed as well as the growth stage of the soybeans.

There have been damage reports and replants particularly in Lambton, Essex, Niagara and Haldimand counties where they have received large amounts of rainfall and crusting became an issue. When doing plant population assessments a stand with 100,000 uniform plants per acre should not be considered for replanting. Research has shown that 100,000 plants per acre has a 98 per cent yield potential on most soil types.

On heavy clay soils 110,000-120,000 plants per acre are necessary for maximum yield potential. Rolling fields after the soybeans have fully emerged compared to rolling immediately after seeding helps alleviate stand losses due to crusting. Rolling can be up done up to the 1st trifoliate stage. There have been reports of seed corn maggot feeding in a number of regions due to the cool, wet weather. Fields planted without Class 12 insecticides that have sufficient stand loss due to certain soil insects including seedcorn maggot may warrant the completion of Inspection of Crop Pest Assessment by a professional pest advisor. If stand loss thresholds for the Class 12 regulations are reached, Class 12 insecticides can be purchased for that farm property. Contact a Professional Pest Advisor and refer here for more information. Bean leaf beetle feeding has also been reported in Essex County. Fields planted with fungicide-only seed should be scouted during the early seedling stages. Spray is warranted if 16 adult beetles per 30 cm of row are found on VC to V2 stage soybeans. If plants are clipped off at the stem, control is warranted if adults are still present and actively feeding.

Forages
First-cut alfalfa has begun in many areas with excellent yields being reported to date. Growers who applied some early season N to forage stands are reporting significant yield boosts. Alfalfa weevil and potato leafhoppers have been present in some areas. 

Canola
Canola emergence has been good to date; however, crop advancement has been slow particularly in northern Ontario. The earliest planted fields are at the 4 leaf stage. Growers in the Timiskaming area are already catching swede midge at this time and are likely going to have to spray sooner than anticipated. Swede midge has also been caught in the Shelburne area but has not yet reached thresholds. Due to the later planted crop and swede midge emergence this year it is anticipated that swede midge feeding will be a significant challenge. There have also been reports of high flea beetle pressure in some fields. 

Edible Beans
Due to the excessive moisture in many areas, edible bean planting is approximately 15 per cent complete. It is expected that the remaining acres will be planted later this week once conditions dry up.
Published in Corporate News
The number of bertha armyworm larvae on a farm last year is not a reliable indicator of what to expect this year. Bertha armyworm populations fluctuate widely from year to year.

Provincial monitoring programs raise awareness of potential outbreaks, based on number of adult moths caught in pheromone traps. Adult counts in June and July can indicate the risk of larvae feeding in July and August. Begin larval monitoring after peak flowering or about two weeks after peak trap catches. Continue scouting until either the mean number of larvae per square foot exceeds the economic threshold (at which point the crop is sprayed) or until the time remaining until the crop is swathed no longer allows for application of a registered insecticide based on the allowed pre-harvest interval.

Often bertha larvae aren't noticed until they move up the canopy and are easily visible during mid to late podding. At this point, chewing on the pods causes visible yield loss quickly. They will lower in canopy before that time, feeding on lower leaves. Assessing your crop early for telltale signs of leaf feeding and becoming aware of your forecast risk will give producers time to accurately assess and time an insecticide application, if needed.

Scouting tips
— Go out in early morning or late evening when larvae are mostly active.
— Mark out an area a quarter-metre square (50 cm by 50 cm) and beat the plants growing within that area to dislodge the larvae. Count the larvae that have fallen to the ground and multiply by 4 to get the number per metre square. Larvae will hide under leaf litter and in cracks, so check closely.
— Sample at least 5 locations (10-15 is recommended) a minimum of 50 metres apart. Do not sample headlands and areas within the crop that are not representative of the field. Use the average number of larvae at the sites surveyed to determine if the economic threshold has been exceeded.
— Scout each field. Adjacent fields may have very different larval densities, depending on how attractive the crop was when the moths were laying their eggs. Adjacent fields may also have different-sized larvae, depending on when the eggs were laid.
— For best results, apply an insecticide as soon as economic thresholds are reached. A single well-timed application of any registered insecticide is usually effective. Check provincial crop protection guides for registered insecticides.
— Apply insecticides early in the morning or late evening when the larvae are actively feeding. Do not apply during warm afternoons.

Click here to see a video of Alberta Agriculture and Rural Development's insect management specialist, Scott Meers, demonstrating how to scout for Bertha armyworm larvae in the field.
Published in Insect Pests
Page 1 of 14

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