Corn planting is essentially complete. Due to variability in rainfall and soil fitness this spring, there is a wide range of crop stages. Early planted corn is now past the V6 stage and approaching row closure in some fields, while late planted corn on heavier textured soils is in the emergence to early V stages. Side dressing continues in many areas. While stands look good overall, there have been some comments about non-uniformity now showing up in some fields where soil conditions may have been pushed at planting, particularly in areas which have remained dry. Corn replants, mostly due to excessive rainfall in 2018, are reported to be below normal. There have been reports of some fields with heavy weed pressure where weed control has been delayed due to high demand for other sprayer activities. Good weed control from emergence to 6 leaf stage is critical for protecting from yield loss in corn.
On June 6, OMAFRA completed its annual Pre-Sidedress Nitrogen Test (PSNT) sampling survey at its zero nitrogen trial locations. This survey assesses soil nitrogen status by measuring natural background nitrogen mineralized from the soil. Average soil nitrate results came back at 12.7 ppm. This is slightly above the long term (2011-2017) average of 11.7, suggesting nitrogen mineralization processes appear normal this spring. The full report and details on the nitrogen status in 2018 corn fields is available online. This survey serves as a general guide. Soil nitrate results are highly field specific, and growers are encouraged to sample their own fields before making any nitrogen decisions.
Most areas of the province have completed planting, though some still continues on very heavy soil textured areas such as Niagara. Due to variability in planting date, crop staging ranges from planted to early emergence for later planted field to 3nd trifoliate for early fields. Thin stands are being observed in many areas. Issues range from soil conditions at planting, heavy rains after seeding resulting in crusting, seed corn maggot feeding, root rots, or extremely dry conditions. Fortunately soybeans are able to compensate for thin stands within reason. Leaving a stand of 90,000 plants per acre on medium textured soils is usually more profitable than replanting. (110 000 plants per acre on heavy clays) For those fields with very poor stands replanting is still a viable option at this date. Feeding from Bean Leaf Beetle has been reported so monitoring is recommended.
A large amount of hay has been cut over the past two weeks. While most dairy hay is complete, some first cut continues this week. Limited rainfall has been conducive for dry hay production as well. Yields have been reported to be good. Quality has been good, with the only challenge reported to be early season grass growth staying ahead of alfalfa due to the cool start in April. Alfalfa weevil has been observed in many areas and scouting is encouraged after first cut this year. Temperature models suggest alfalfa weevil development may be delayed, and could still pose a risk to early regrowth. Control is warranted if there are two or more active larvae per crown, or 4–8 larvae per 30 cm by 30 cm (1 ft2).
The winter wheat crop is progressing well; however, some wheat stands are variable and considerable discolouration is still evident. In the driest areas wheat is starting to flare up due to a lack of moisture. Fusarium Head Blight fungicides (T3) have been going on as wheat progresses through the anthesis stage. A number of acres in the far southwest of the province did not receive a T3 fungicide as warm temperatures moved the crop quickly through the ideal application window. Stripe rust was reported on June 5th in the St. Mary’s area on a susceptible variety. A second field has since been reported in the Clinton area. Disease levels continue to remain low and as temperatures continue to increase, stripe rust becomes less of a concern. If growers are still considering a late T3 fungicide application for stripe rust control, pre-harvest intervals must be considered.
Canola is progressing well, with earlier planted fields in southern and eastern canola growing regions now at green bud stage or bolting. In northern regions the crop is approaching full rosette and expected to start bolting in the next week or two. Flea beetle is being reported, though pressure is generally low. Flea beetle must feed on the seedlings to be exposed to seed treatment insecticides. Foliar insecticide application is not warranted until at least 25% foliar feeding is observed, and once the crop is at the 4 leaf stage it can likely outgrow the feeding damage. Swede midge is now being observed, although populations are reported to be relatively low. Swede midge pheromone traps should be in place and checked every few days through to bolting. With some early reports of Cabbage Seedpod weevil, monitoring is recommended.
A large portion of edible bean acres have been planted, with many growers done or expecting to be done within the next week. Planting continues in some localized areas where rainfall had delayed field operations, or for shorter season beans such as Cranberry beans. Early reports suggest good stands in most cases, with the exception where seedbeds were overly dry. Lack of heavy rainfall events over the past two weeks has limited crusting and other rainfall related plant loss issues.
Foliar insecticide applications are occurring in many canola fields and some second insecticide applications to control flea bettles. There are also more reports of reseeding of canola because of feeding by flea beetles, particularly in the Southwest and Central regions.
The update also warns of early season infection of blackleg in canola, especially if the crop endured damage from hail, wind, frost or insect feeding. The question for growers is whether or not to use fungicide at the herbicide timing to protect their crop from blackleg infection. The update cites studies that show early fungicide application can reduce disease and increase yield. However, the growing conditions present in the studies are specific and there are other factors to consider. | READ MORE
Lumiderm seed treatment provides soybean seedlings with extended protection against bean leaf beetle and soybean aphid. Protecting vulnerable seedlings from these two damaging insects leads to more uniform and healthier plant stands, allowing the crop to achieve its maximum yield potential at harvest. Lumiderm contains a unique Group 28 insecticide that helps growers manage the threat of resistance, and has a favourable environmental profile, according to a press release.
This year, the survey teams would like to check pea and wheat fields. They will survey for pea leaf weevil in late spring and survey for wheat midge and wheat stem sawfly in the fall after harvest.
“In addition to the rest of the province, we are looking for pea fields up into the Peace Country because the pea leaf weevil has been confirmed into that area, and we want to expand our survey there,” says Scott Meers, insect management specialist with AF. “We are looking for fields that producers would be happy to have us check. For allowing us on their fields, we will provide those producers with a report of the survey results.”
Meers would also like to increase in the number of bertha army worm traps in Alberta. “We are trying to get four to five traps per county across the province. If you are interested, we will hook you up with all the materials you will need.”
For agrologists and producers who have monitored for the bertha army worm adults in the past, now is a good time to check those traps to see if they need to be repaired or replaced. “They are plastic, and plastic in the wind and sunshine tends to break down after time. Let us know if they need to be upgraded or replaced,” adds Meers.
“What makes this app unique is that it works the beneficial insects as well,” adds Wist. “It works in the predators and the parasitoids that help to keep the aphid populations in check. When you’re scouting for the aphids, you’re also scouting for the natural enemies.”
The Cereal Aphid Manager is based on a model built by researchers at AAFC. The model treats the grain field as an ecosystem and takes into account many complex biological interactions including:
- The number of different natural enemies of aphids in the field and how many aphids they eat per day.
- The lifecycles of aphids and their enemies including their developmental stages, egg laying behaviour, population growth rate, lifespan, etc.
- Types of non-crop habitats that insects around the field that the different insects prefer.
'Soil Your Undies' experiment in EloraMon Jul 23, 2018 @10:00AM - 11:00AM
Intercropping Field DayTue Jul 24, 2018 @10:00AM - 05:00PM
Manitoba crops-a-PALOOZAWed Jul 25, 2018 @ 8:00AM - 05:00PM