Fall is the most effective time to manage certain weed species. The recommendations seem clear-cut:  winter annuals = fall herbicide application/tillage; annuals = no fall management.  But figuring out the life cycle of the weeds in your field this fall is the catch……

Bromes, cleavers, chickweed, night-flowering catchfly, narrow-leaved hawk’s-beard, shepherd’s-purse and stinkweed are all facultative winter annuals, meaning that they can germinate in either the fall or the spring depending on environmental conditions.  These weeds are often best managed in the fall, if populations warrant it.  In general, waiting until about this time of year maximizes fall-germinating flushes of winter annuals.  If using a herbicide, consider weed stage and the weather forecast, prior to application.

The problem is, given the right conditions – like the long falls and mild winters we’ve had the last few years –several of our annual weed species can also successfully overwinter:

Biennial wormwood – Despite its name, biennial wormwood behaves like an annual in agricultural fields.  When scouting, estimate the average growth stage of biennial wormwood populations in a field.  If the majority of the plants have already set seed, a fall herbicide application won’t help.  An application may be worthwhile only if there is a large flush of biennial wormwood that haven’t set seed and are less than ~3 inches tall.  Herbicide tank-mixes containing glyphosate + group 4 are more effective than glyphosate + group 2 on this weed.

Round-leaved mallow (RLM) – This annual weed can act as either a winter annual or a short-lived perennial, although it is more sensitive to freezing than our common winter annuals.  Mild winters in 2015 & 2016 provided the right conditions for RLM to overwinter, allowing it to become (even more) problematic in certain fields over the last few growing seasons.  Long range forecasters are predicting a harsh winter across the prairies this year, which should control RLM.  However, if you have little faith in forecasts and decide to apply a herbicide, glyphosate mixed with either Distinct or DyVel DSp has activity on this weed.


Round-leaved mallow post-harvest

Stork’s bill –
Like biennial wormwood, stork’s bill tends to be predominantly an annual in Manitoba.  If this is a problem weed for you, scout affected fields to determine average weed stage.  Again, if most of your stork’s bill has set seed you’re better off working on a plan for next year.  Stork’s bill, especially larger plants, is relatively tolerant of many herbicides.  If you decide to apply a herbicide because of stork’s bill this fall, glyphosate + group 2 or glyphosate + group 2 + group 4 on weeds up to the 4 to 6 leaf stage is probably your best bet.

Submitted by: Jeanette Gaultier, Provincial Weed Specialist, Manitoba Agriculture

Information on more weeds and their life cycles is available at: www.gov.mb.ca/agriculture/crops/weeds/
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Tips to Marketing Downgraded Crops

Over the past few weeks, we’ve heard about the impact of the poor weather conditions over the harvest period on the quality of harvested grain.  With the crop off the field and into the bin, marketing now becomes the focus of many producers.

In the attached article (updated from 2014) by Gary Smart, Farm Management Specialist with Manitoba Agriculture, he provides excellent information to cope with downgraded crops.  Some highlights include:

  • When marketing poor quality grain, be prepared and don’t panic, especially right at harvest time.
  • Know the quality and find a buyer who will offer the best value.
  • Take good samples. Without thorough samples, it is tough to know what is actually in the bin.
  • Communicate with the buyer if already some of this year’s crop is already contracted.
  • Unless cash flow is an issue on the farm, being patient could be the best action to take as new markets may arise for poor quality grain.

ARTICLE: Marketing Poor Quality Grain (2016)

For further information, support and resources, contact the Manitoba Agriculture’s Farm Management Team at http://www.gov.mb.ca/agriculture/business-and-economics/farm-business-management-contacts.html

Submitted by:  Pam de Rocquigny, Provincial Cereal Crops Specialist, Manitoba Agriculture

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Minimum Air Temperatures – September 13/14, 2016

From Manitoba Agriculture’s AgWeather Program, a map showing minimum air temperatures reached September 13/14:


In addition, the Crop Weather Report is a weekly summary of temperature (max., min., avg) and total rainfall along with seasonal accumulations of degree days, corn heat units and rainfall (actuals and % of normal) are provided for about 50 locations in the five regions.

Following are links to weather maps in pdf format for the time period of May 1st to September 11th:

The above maps will be updated every Monday during the growing season. They are available on the Manitoba Agriculture weather web site at http://www.gov.mb.ca/agriculture/weather/index.html .

For more information or to subscribe to the weekly Crop and Weather reports send your request to [email protected].

Follow Manitoba Agriculture on Twitter at @MBGovAg to get these seasonal reports and more.


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It’s That Time of Year – Talking Fall Frosts in Manitoba


As we enter in the later parts of the growing season, fall frost enters the minds of most people involved in the grain industry.  As everyone knows, frost can have an impact on a crop’s quality and yield.  There were a few areas reporting a light frost event the morning of September 14th.

The extent of frost damage to a crop will depend on several factors. The species, stage, and hardening of the crop, the soil type and soil moisture, the actual air temperature, the duration of freezing, and the rapidity with which freezing takes place are all important. A drop in air temperature of short duration will cause less damage than a prolonged periodthe same low temperature. When the air temperature drops to 0°C, cereal and other crops may not sustain damage. Rather, damage or total loss is more common when minimum temperatures drop below -2°C, often referred to as a killing frost.

Given its sporadic nature, long-range forecasting of frost is nearly impossible. Rather, the climate record of an area is used to determine probable dates of frost based on long-term temperature records. While this will not provide an actual frost date in a particular year, it will present the likelihood that frost may occur on a certain date. This can be a valuable planning tool.

The Manitoba Ag-Weather Program released updated FIRST FALL FROST MAPS in 2014 which are made from the new township gridded normal from a wider dataset of 1950-2010:

For additional information, please visit Manitoba Agriculture’s AgWeather Program at http://www.gov.mb.ca/agriculture/weather/agricultural-climate-of-mb.html.

Submitted by:  Pam de  Rocquigny, Provincial Cereal Crops Specialist, Manitoba Agriculture

Manitoba Agriculture on Twitter: @MBGovAg
Manitoba Agriculture on YouTube: www.youtube.com/ManitobaAgriculture
Manitoba Agriculture website: www.manitoba.ca/agriculture


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So we had a Frost on our Soybean, Now what?

The first step in accessing frost damage is asking how cold it was last night. A light frost of -1°C for short durations may clip off a few off the top leaves with no effect on yield. The concern begins when a killing frost at least -2°C occurs for an extended period of time. In this situation you will see frozen leaves and pods throughout the canopy.  This may cause quality issues and yield reduction if the crop has not reached full maturity.

See the latest MB Ag Weather latest frost map: http://www.gov.mb.ca/agriculture/weather/pubs/minimum-air-temperature.pdf

What growth stage are your beans at, see http://www.manitobapulse.ca/soybean-staging-guide/ as a reference.

A killing frost at the R8 growth stage will see no yield or quality loss. The R8 stage is when the leaves have dropped off, all pods are brown, and seeds rattle within the pods when plants are shaken.

If however your beans are at the R7 growth stage, (which means one pod on the plant has reached its mature color), research has shown yield loss can range from 5-10 % dependent upon the severity of the frost. Quality issues in the way of green seed may also occur.

Finally, if your beans are at the R6 growth stage-(this is where pods containing a green seed that fills the pod cavity at one of the four uppermost nodes on main stem), yield losses can range from 20-30 %.  You will also have green seed issues which can also lead to marketing concerns.

There are a few areas in Manitoba where the beans are at the end of this R6 growth stage.  Most of the beans in Manitoba are at the R7-R8 growth stage. A light frost should not affect yield and quality for these beans. If beans were at the R6 growth stage and a hard frost occurred yield and quality losses would be noticeable.


Picture: Light frost damage on soybeans near Hamiota, 2016.

Photo from L.Grenkow, Manitoba Pulse Soybean Growers

Submitted by: Dennis Lange, Industry Development Specialist-Pulses, Manitoba Agriculture


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Canadian Grain Commission’s Harvest Sample Program


Photo Credit: Canadian Grain Commission

Mitchell Japp, the Provincial Cereal Crops Specialist with the Saskatchewan Ministry of Agriculture, recently wrote an article on the Canadian Grain Commission’s Harvest Sample Program – what it is, how to request a sample kit in order to submit a harvest sample, and getting results.  The complete article is available here: Harvest Sample Program.

The CGC is providing a valuable service to individual farmers and industry with the Harvest Sample Program, but it takes participation for it to work.  I would encourage Crop Chatter subscribers to click on the link and read Mitchell’s article!


Submitted by:  Pam de Rocquigny, Provincial Cereal Crops Specialist, Manitoba Agriculture

For more information, visit the Canadian Grain Commission page.
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The Canadian Crop Hail Report – Release Date of August 11th

The Canadian Crop Hail Association represents the companies that sell crop hail insurance to producers in Western Canada. The Hail Report is released every second Thursday during the hail season to provide information on storms, claims and related issues. The report is compiled by McArton & Associates Communications at Dilke, Saskatchewan.

The following is the report for Manitoba from the August 11th Report:

Hail claims in Manitoba remain above the five-year average. A July 20 storm that moved in from the US through Darlingford and Thornhill saw some areas reporting hail that lasted for periods as long as 45 minutes, resulting in severe crop damage. That storm continued north-west towards Manitou and Pilot Mound, lessening in severity as it continued on to the Holland and Treherne areas. On that same day, a storm travelling east from Saskatchewan caused significant damage in areas around Hamiota and Minnedosa. Hail activity in the province has slowed dramatically since those events.

Storm dates and locations of significance for this period included:

  • July 19: Cardale, Darlingford, Hamiota, Holland, Minnedosa, Morden, Neepawa, Notre Dame De Lourdes, Rapid City, Solsgirth, Somerset, Strathclair, Swan Lake, Treherne
  • July 20: Brandon, Dunrea, Elgin, Haywood, Holland, Justice, Killarney, Melita, Minnedosa, Neepawa, Reston, Rossendale, Sinclair, Somerset, St. Claude, Waskada, Winkler
  • July 30: Minto
  • August 1: Hamiota
  • August 3: Souris

Full report is available at The Hail Report_August 11.16

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Harvest 2016 is here as winter wheat and fall rye harvest has started in some areas of Manitoba. With favourable weather, crops are advancing quickly so now is a good time for a refresher on pre-harvest management!

As agronomists and producers, there are a few distinctions you need to be aware of between the pre-harvest herbicide products that are available for pre-harvest management. When done correctly, a pre-harvest application can provide a number of benefits including maximizing yield and quality, allow for direct combining of standing crops, perennial weed control and managing weed escapes from the growing season, and can speed up harvest timing.

However, it is critical to know the differences between the herbicide options to manage product expectations, and to ensure application is done correctly to make your crop export ready! The following are some key points to remember when considering your pre-harvest management.

  • The most commonly used active ingredients used for pre-harvest management are glyphosate, diquat (ex. Reglone), saflufenacil (ex. Heat), carfentrazone (ex. Aim) and flumioxazin (ex. Valtera). There are also products that are pre-packaged mixes of active ingredients (ex. CleanStart with glyphosate and carfentrazone).
  • Products such as Reglone or Heat are desiccants. GLYPHOSATE IS NOT A DESICCANT. Desiccants and glyphosate work very differently, usually require different application timings and parameters, and provide different benefits.
  • Desiccants that contain diquat (e.g. Reglone, etc.) have been registered the longest in many crops and are the gold standard to which all other desiccants are compared. Diquat rapidly dries down green plant material, with desiccation typically occurring within hours to a few days. In fact, diquat fast acting nature sometimes works against itself, by limiting uptake by drying plant material, which is why the labels recommends applying these products at dusk or on cloudy days.
  • Newer desiccants, such as Aim, Heat and Valtera, also result in the dry down of green plant material. Research has shown that Heat and Valtera are often just as or more effective than diquat for desiccating crops, and usually only take slightly longer to do so. Aim, on the other hand, is relatively slow acting, which makes it an ideal partner for glyphosate. And research has shown a synergistic effect when Aim and glyphosate are tank mixed (i.e. CleanStart), something not seen with other desiccants. Opposite to diquat, these desiccants are best applied on sunny, warm days.
  • Coverage is important for these contact products, so be sure to keep water volumes up!
  • GLYPHOSATE IS NOT A DESICCANT but can enhance dry down of crops. Research has shown that, compared with untreated crop, glyphosate can improve crop dry down after 7 to 14 days (depending on the weather). But glyphosate typically does not dry down crops as consistently or to the same extent as the true desiccants.
  • However, glyphosate is a popular pre-harvest choice for many growers since, as the only systemic, is provides control/suppression of weeds, including winter annuals and perennials. Desiccants will also dry down green weeds, but only provide top growth control.
  • Proper application timing is critical regardless of the product used. Always refer to and follow the product label for the correct timing and rates. Remember, desiccants or glyphosate neither bring about nor speed up crop maturity. However, it can decrease the time between when the crop has reached maturity and when the crop is harvested.
  • Proper application timing is especially important for glyphosate. When applied too early, glyphosate residues could accumulate in the grain and may exceed Maximum Residue Limits (MRLs) of important export countries.
  • Residues for the contact products (diquat, Aim, Heat and Valtera) are usually very low because of their contact nature. But that doesn’t mean that these products are without MRL concerns since, in many cases, residues tolerances can be exceeded simply because an MRL has not been established in all markets.
  • Cereals Canada, Canola Council of Canada and Pulse Canada have information available through their “Keep it Clean” initiatives. Please refer to the following websites for additional information for meeting export standards, why MRLs matter, pre-harvest interval information, and herbicides that should not be used.

Submitted by: Jeanette Gaultier, Provincial Weed Specialist, and Pam de Rocquigny, Provincial Cereal Crops Specialist, Manitoba Agriculture

Herbicide options for use as a harvest aid or desiccant before crop harvest are listed on Page 63 of the 2016 Guide to Field Crop Protection: https://www.gov.mb.ca/agriculture/crops/guides-and-publications/#gfcp

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Updated Manitoba Agriculture Weather Maps – May 1st to July 17th

Updated maps for the time period of May 1 to July 17 are now available from Manitoba Agriculture!  Also included is the 7 day rainfall accumulation map covering the time period of July 11 to July 17.

Following are links to weather maps in pdf format:

The above maps will be updated every Monday during the growing season. They are available on the Manitoba Agriculture’s Ag weather web site at http://www.gov.mb.ca/agriculture/weather/index.html .

For more information or to subscribe to the weekly Crop and Weather reports send your request to [email protected].

Follow Manitoba Agriculture on Twitter at @MBGovAg to get these seasonal reports and more.

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Manitoba Insect & Disease Update – Issue 10: July 20, 2016

The Manitoba Insect and Disease Update is now posted at: http://www.gov.mb.ca/agriculture/crops/seasonal-reports/insect-report-archive/insect-report-2016-07-20.html

Some highlights from the update:


  • Pea aphid levels are still a concern in some pea fields, although many fields will be getting to the stage where management would no longer be economical.
  • Aphid levels have dropped in many cereal fields where previously levels had been increasing. High levels of natural enemies have been noted in some of these fields, and some intense rains may have also contributed.
  • In some areas of Central and Southwest Manitoba, greater than 90% of the wheat midge are expected to have emerged. In many areas of Manitoba about 50 to 90% of wheat midge are expected to have emerged. A reminder that wheat that has already produced anthers is no longer susceptible to feeding by wheat midge. Even if adults are still active in these more advanced fields, the larvae will not feed on the grain.
  • Egg masses of European corn corer are starting to be noted in some fields of corn. So far there are no reports of high levels, but now is the time to be checking fields for the egg masses.

Figure 1. Egg masses of European corn borer.

Plant Pathogens:

  • Some infections of blackleg in canola and fusarium head blight in cereals have been reported.
  • A few cases of loose smut in barley were also reported.
  • Two positive identifications of Goss’s Wilt in corn were made. The positive identifications were made based on immunostrips and/or polymerase chain reaction (PCR) assays.

Submitted by: John Gavloski, Entomologist & Pratisara Bajracharya, Field Crop Pathologist, Manitoba Agriculture

Manitoba Agriculture website: www.manitoba.ca/agriculture
Manitoba Agriculture on Twitter: @MBGovAg
Manitoba Agriculture on YouTube: www.youtube.com/ManitobaAgriculture


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