Preliminary canola variety results: Fort Cobb

It is important to remember these are preliminary results and numbers may change between this post and the final publication. Additionally, oil content will be available at a later date. Please remember to keep checking in for other variety trial locations and updated information.




Preliminary Canola Variety Results: El Reno

It is important to remember these are preliminary results and numbers may change between this post and the final publication. Additionally, oil content will be available at a later date. Please remember to keep checking in for other variety trial locations and updated information.

Grain yields from the OSU conventional winter canola variety test at El Reno, OK.  All yields were adjusted to 10% moisture.
Grain yields from OSU glyphosate resistant winter canola variety trial at El Reno, OK.  All yields were adjusted to 10% moisture.

Preliminary Canola Variety Results: Kingfisher

It is important to remember these are preliminary results and numbers may change between this post and the final publication.  Additionally, oil content will be available at a later date.  Please remember to keep checking in for other variety trial locations and updated information. 

Preliminary grain yields for the OSU conventional winter canola variety trial at Kingfisher, OK.  All yields are adjusted to 10% moisture content.


Preliminary grain yields for the OSU glyphosate resistant winter canola variety trials in Kingfisher, OK.  All yields adjusted to 10% moisture content.



Canola Update: Harvest continues but slowed

The first passes of canola harvest 2016 have already begun.  Canola has begun to be swathed for a majority of the state.  While progress has been made, overall swathed intensions have been slowed due to the wet conditions.  The weekend of May 21st and 22nd are lining up to allow producers to get into fields, that have not received abundant rain, to proceed with swathing.  The sunny and warm conditions predicted might allow producers to get a lot of acres that have begun to mature in windrows.  If producers do not get swathing done this weekend or very early in the week, the window of swathing may be closing for many.  While maturation has been slowed by recent cool weather, the warm weather that might help a lot of producers swath this weekend could result in quite a few acres reaching or surpassing critical swathing time during the rainy conditions predicted for the coming week.  This will leave a lot of producers questioning whether to swath earlier than they intended to or chance waiting and potentially having to rely on direct harvesting. 

As far as early swathing is concerned, growers need to wait on the main raceme to reach the 30% color change.  If the crop is swathed prior to this point, there is a risk of many pods not fully maturing, which could result in high levels of shriveled seed and green seeds.  While shriveled seeds can be problematic, any degree of green seeds in a load could result in heavy dockage at the delivery points resulting in low quality loads.  If this is the current situation for growers, they should probably wait to see if the rainy conditions of the coming week are less severe than currently predicted and rely on later swathing or direct harvesting.

For producers that are past the 30% but not quite at 50-60% and intend to swath, now is probably the best time.  Canola that is this mature will potentially over-ripen in the field if the predicted conditions are true.  This over-ripened canola will only be able to be direct harvested and could be at risk to higher amounts of in-field shatter due to high winds or hail, if predicted.  Swathing ahead of a rain has been thought to be a bad practice.  In actuality, this can result in no difference or potentially slightly benefit the crop.  The benefits of swathing right ahead of a rain occur when rapid drying may occur following.

Swathed canola ahead of the potentially wet conditions the coming week.  Photo courtesy of Dr. Ron Sholar

Moving from swathing to direct harvest is a decision that can be made at any point in the coming days to weeks.  The main focus for growers moving this direction needs to be keeping a close eye on the moisture of the crop.  Canola should be cut when the crop reaches 8-10% moisture.  Direct harvesting canola can still result in very competitive yields and should not be thought of as lowering yield potential. 

Overall, all three situations may occur across the state over the next several days.  It should be noted that swathing or direct harvest are both viable options for canola within the state and yield can be very comparable.  However, growers should do what is best for their production systems.  These are the last few decisions growers will have to make in field to ensure the good looking canola crop in the field makes it to the bin. 

Canola harvest options and decisions

It may be hard to believe but harvest for this year’s canola crop is right around the corner.  The combination of a mild winter and environmental conditions during the spring have pushed the crop several weeks ahead of average in many parts of the state.  With harvest being close for many producers throughout the state it is time to start thinking about harvest management for this year’s canola crop.  However, before determining how to manage harvest, one needs to decide harvest method that will be targeted for their crop. 

Harvest method:  Producers have two very viable options (direct harvest or swathing) for harvest of canola within the state.  A third option (pushing) does exist and may be suited for certain areas within the state but information is relatively limited so the focus of this conversation will be on swathing and direct harvesting. 

The decision to swath or direct harvest comes down to several decisions that producers have to make at a farm level as well as a field to field basis.  Overall, optimum yields are achieved in best case scenarios from direct harvesting the crop, allowing the crop to dry-down in a more traditional manner.  However, as producers know optimum conditions rarely exist.  In addition to yield, direct harvesting has the potential to produce the highest quality seed with better protein and oil content.  Furthermore, having the crop to stand in the field allows the quality to be maintained through a wide-range of environmental conditions, such as hot weather at harvesting and poor moisture conditions after swathing.  This method also has the best resilience to harvest in heavily tangled and extremely thick stands (something a lot of producers may be faced with in the coming weeks).  However, direct harvesting has the highest potential yield loss when dry-down and harvest conditions are not optimum.  This point is emphasized during severe storms.  Hail as small as pea sized can dramatically reduce crop productivity, especially late into maturity.  This would make direct harvesting more a high risk, high reward option.

While swathing does not have the overall yield potential that direct harvest does, what it does offer is flexibility to the grower.  Swathing the canola allows the grower to have a little control over when the canola matures and at what rate.  It can also offer the grower the opportunity to harvest up to 10 days prior to direct harvesting, thus allowing for more acres to be harvested in a timely fashion or allows for harvest of canola prior to moving on to wheat.  Two of the biggest advantages outside of flexibility that swathing provides is decreased shattering potential and allows for the field to even out within the windrows to allow for a more uniform crop.  There is only one major limitation to swathing and that is the potential for decreased yield and quality, which can be as high as 30% but will typically range from 0-10% yield loss.  Other issues exist for swathed canola but they can be addressed by optimizing their harvest/swathing activities. 

Managing harvest activities:

Direct harvest:  The biggest management with direct harvesting comes with when to harvest and setting up a combine.  Producers should allow for the crop to dry to 8-10% moisture before the crop is harvested.  Harvesting with more moisture and drying through forced air can be successful, however, results have been varied.  It is best to wait for the crop to dry down and use combine management to minimize shattering. 

If growers want to compare combine setup to wheat, the general rule is to slow down to about 3/4 of what is typically done for wheat harvest.  This will include ground speed, reel speed, and cylinder speed.  In addition to speed, the reel should be set high and moved back over the grain table as far as it allows.  Fan speed can be set similar to wheat, with no major advantage to slowing the fam speed.  Canola is pretty easy to thresh, so opening concave up until whole dry pods are not threshed is better than too narrow and grinding stems (which can increase overall seed moisture).  Lastly, make sure the sickle is sharp, a dull sickle can lead to increased shatter loss in front of the combine.  If the harvester believes the combine is set properly, drive a test cut and get out and look behind the combine.  The rule of thumb is that 115 seeds per square foot is equal to 1 bushel yield loss per acre.

Swathing:  One of the most important decisions, if swathing the canola is desired is when to actively swath the canola.  Maturity is determined primarily from the main stem of the canola.

Figure 1. Identifying the main stem, this will be the raceme used to determine maturity


Figure 2. Determining color change on percentage of main stem.  Use the length of the stem to help estimate maturity.  In the picture the arrows should be at 33%, 50%, and 75%, respectively.

Once the main stem is identified; it should be broken up into sections.  When determining maturity, we look at color change.  Seed color is distinguished as changed when it possesses small patches of brown to black color (spotting).  For swathing purposes. we would like to see at least 30% seed color change (color change of a majority of the seed within the pod in at least 30% of the main stem); however, lower yield and quality loss are typically seen when the grower can delay swathing until 50-70% seed color change.  The risks associated with higher color change when swathing is both increased shatter due to swathing or rapid drying.  Once a producer has determined that the plant has sufficient color change, producers need to ensure there are no translucent or water seeds within the branching racemes.  If canola is swathed with higher amounts of these seeds, a good fraction of yield loss can be experienced especially if side branches makeup a large fraction of the overall plant.  Once it is determined that the crop can be swathed, producers need to make sure the environmental conditions over the next several days are conducive for quick but quality dry-down.  If soil moisture has been limited and hot, dry conditions are in the forecast, swathed canola can dry-down too quick and not allow for the crop to successfully “cure”.  This will result in increased seed shrinkage and potentially higher percentage of green seed. 

Figure 3. Progression of color change for winter canola at maturity.  The top left picture shows not color change throughout the pod with some soft watery seeds. The top right picture shows spotting color change throughout the pod, with firm seeds and limited translucent seeds throughout the plant. The bottom left picture shows color change throughout the pod with some spotting still on less mature seeds. Bottom right picture shows full mature color change.  Swathing can begin when at least 30% of the pods exhibit pod color of at least the top right and bottom left.

Caution should be placed on ensuring that minimum loss occurs in the windrow or as the canola is being picked up.  Canola should be ready to harvest in 7-14 days after swathing, but if the crop contains high amounts of immature seed or seed moisture it is better to let the crop sit in the windrow longer to minimize green seeds in the load as only few of these can result in high grade loss.  Windrows are best picked up using a rubberized draper belt. These belt types have rubber or synthetic fingers and are preferred when harvesting canola as the gentle action helps reduce shattering losses. The aluminum pick-up is more suited for bunched windrows.  Crop lifter attachments that are the width of the windrow will lift it into the header in most cases. The rest of the cutter bar may be covered to prevent or reduce the amount of second-cut stubble entering the combine.

Use of replacement crop behind wheat

Determining wheat yield loss:

The question on to how to manage wheat production that has suffered high potential yield loss can be quite challenging.  High disease pressure and periods of dry conditions have been the main focus of this season’s wheat crop, but the recent storms have added to these issues with fields having >50% lodged wheat.  While this may be a great concern when viewing this crop initially, a lodged or damaged wheat crop may still have decent yield potential.  It is important to remember that, 50% lodging does not necessarily represent 50% yield loss. Many times the wheat crop will stand back up days or weeks after a lodging event.  Overall, for a questionable stand of wheat, the best course of action might be to keep the stand and get the most yield possible from the crop.  If you are considering planting a crop after failed or abandoned wheat, there are some important considerations before making the jump.

Insurance potential for a replacement crop

This will be the biggest catch for terminating a current wheat crop for a replacement summer crop.  In many scenarios, once the wheat crop has begun to head this will be considered a double crop situation.  In this instance many companies will not allow insurance to cover the following crop.  Even if insurance is available for this double-crop scenario, at least three year yield potential numbers are frequently the minimum needed to receive this support.  The best first steps for a grower to take when evaluating their fields planting of a replacement crop after a termination or hay is to check on their individual coverage and talk to their representatives before any action is taken.

Things to consider before moving into a summer crop:

Herbicide restrictions:

One of the most important considerations for determining if and what potential crop could be planted following a non-harvested wheat crop is the chemistries used during the year.  Table 1 gives rotational restrictions on some commonly used winter wheat herbicides.  While this provides a summary or shortened list of herbicides and their rotational restrictions, producers should check individual labels if other herbicides were used.  It should also be mentioned that minor plant injury could occur past the stated months following application given differences in soil conditions such as pH, soil moisture, and soil temperature.


Heavy wheat residue:

One thing that needs to be decided is how the grower will manage the heavy wheat residue associated with the failed crop.  Certain situations exist that may result in limited to no residue (i.e. haying or heavy disease pressure); however, most producers will be faced with high residue load which may potentially be heavily matted and may pose challenges for producers to plant through.  In these situations, producers may need to resort to tillage.  The amount and intensity of tillage will greatly depend on the amount of residue left in field.    In high residue situations, producers may need to run one or several primary tillage practices followed by a secondary or finishing tillage event.  However, in lower residue conditions or if the producer has access to no-till equipment, no tillage may be needed to achieve a successful stand.

Overall cropping system:

When deciding to terminate an existing wheat crop and/or to plant a successive crop, decisions need to be evaluated at a systems level.  Growers need to ask themselves whether this makes sense within their system and if it fits into their long-term system goals.  If the original intent for the system was to double-crop following wheat harvest, it needs to be determined if the remaining economic benefit without the yield from the wheat crop.  This may be at least partially alleviated if any profit can be made from the wheat crop (i.e. hayed) but needs to be evaluated on a specific field basis.  The next question will be what the successive crop would have originally been?  If a summer crop is planted, some systems will need a winter fallow as to not overstress the system, harvest the summer crop prematurely, or plant the successive winter crop past the appropriate timeframe.  In this case it needs to be determined if that is suitable for the long-term system goals.  Many of these scenarios exist and each could be beneficial or not within individual systems; however, growers need to evaluate these individually and determine what works best for their current situation and their long-term production goals.

Overall, the decision to move to a replacement crop can be very challenging.  It cannot be stressed enough that in most situations maintaining the existing crop is likely the best option for most producers.