Friday, May 22, 2015

No Blanket Necessary

This little guy is an example of the most developed soybeans currently in the neighbourhood. A significant amount of angst and anxiety is being spent worrying about the possible frost for tonight and Saturday.  If temperature predictions are correct and -1 degree is the actual low everyone can stop worrying. Soybean tissue can stand frost better than corn.  Trust me.  They will be fine.

If your corn field looks like this, some action is required.  In the bad old days before glyphosate tolerance was bred into crops we had issues spraying crops like one under the current weather forecast.  Folks that made herbicide recommendations in the 80's and 90's  knew that effective weed control and excellent crop safety were two descriptions that did NOT apply to most herbicides of the day.  As a tadpole agronomist in the late 80's I could count on spending the month of June dealing with herbicide injury caused by weather interactions coming back to haunt our management decisions surrounding herbicide choices and timing.  The yield losses at times were significant.
Vlado Puskaric, the legendary Pioneer corn breeder of my generation never understood why, to use one example dicamba, was allowed to be registered on corn.  He was like a mama bear protecting her cubs and anything that hurt the children was public enemy number one and this included many herbicides of the day.  I remember not having any defense when he cornered me, other than to say weeds caused big problems too.  He would then stomp off with smoke coming out his ears.
Fast forward to today.  If we were still working with 30 year old herbicide technology, the risk of injury to emerged corn given the low temperatures of the next two nights would be substantial. Even older products like Dual are much more gentle to the crop now than they used to be and still provide excellent weed control.
Thanks to technology we can and probably should spray the corn crop shown above.  The safest route, assuming it is glyposate tolerant corn is simply glyphosate.  If you want to add a little bit of Calisto or Peak go ahead, but the more combinations you use the more the plant will have to work to break them down.  A second application will be necessary and that is when a tank mix can be applied to help out with weed resistance management.      
The risk to choosing not to spray is wet weather.  If the next week turns wet and keeps the sprayers out of the field then there will be yield loss from the uncontrolled weeds.  A wet week is hard to envision, however we need to ask what is the worst thing that could happen.  At some point it will rain and then it might not stop.  So get the weeds under control now.  The risk of herbicide injury is much less than the risk of uncontrolled weeds.  How times have changed.

Wednesday, May 13, 2015

The Clock Is Runnning

The 2015 crop season is off to a very quick start, at least for corn and soybeans. As of today May 13, close to half of the corn crop is emerged and 70% of the soybeans are planted with the first planted fields also beginning to emerge. Visions of 250 bus corn and 70 bus soybeans are dancing in our head.

Rainfall has been mostly non-existent except for a few non-measurable light showers in the last 3 weeks.  Concern about dry soils has been the lead topic of discussion. This grim sounding concern about soil moisture is understandable, but misplaced.  As long as the crop emerges, dry soil is of no concern to the young corn and soybean plant.  Small plants have a very low water requirement and will be very content for several weeks yet, providing the seedbed condition is good. A well structured seed bed allows the primary root system to establish and sustain the plant.  If the seed bed was too wet when you planted, the primary root system will struggle and the need for rain is greater.
If your tillage practices have left you with no soil moisture and soybeans to plant there is a decision to be made.  Soybeans can be planted 2.5 inches deep if that is what it takes to get to good soil moisture.  The risk is planting deep into soils that have enough moisture to initiate germination, but not enough moisture to sustain emergence.  Soybeans imbibe water, swell and then die under these conditions. Seeding depth in dry soils is an extremely tough call to make.  The other choice is to wait because you still have time on your side.  Lots of 50 bus soybean yields have been produced with late May planting dates.

The prospects for winter wheat is a mixed bag of extremes and ultimately a tale of two crops.  Wheat fields planted following edible beans are good to excellent.  One benefit of the dry soil conditions is low annual weed pressure. Annual weeds in the wheat crop have been a no-show for the most part.  Wheat is very competitive against weeds and at this point any weed emergence will have zero effect on yield. This only applies to the good wheat fields.
The wheat crop after soybeans is a different story that begins with planting dates.
I believe this picture paints the story more accurately than words.  The wheat on the right was planted October 13 and while not perfect is certainly acceptable.  The wheat on the left was planted on October 27. The two week break was due to a delay in harvesting IP soybeans.  Throughout this area the mid October through early November planting dates are in trouble.  The combination of late planting dates and wet soil conditions that never improved is the problem.
These fields are typically full of thin spindly wheat plants that have no vigour.  They appear to be a bunch of runts.  Instincts are telling me they will always be runts. When rains finally come, the thin spots will become weed patches.  Some, including myself have already pulled the pin on this questionable wheat and re-planted to corn and soybeans.  
Why is this wheat so poor?  Peter Johnson believes it is a lack of cold tolerance. Wheat needs to get past the one to two leaf stage in order to develop the cold tolerance required to survive a hard winter. Kind of odd since you can frost seed wheat and make a crop, but that is a different matter.  I believe there is a grain of truth in Peter's assessment, however it is a very fine line.
This is wheat planted last November 4 and protected by a bush on the south side of the field.  The same field 200 ft from the bush line had a completely different look.
This field was under 2 ft of snow all winter.  I skiied across it numerous times.  This cold tolerance or lack of cold tolerance that Peter speaks of is a matter of a few degrees.
Regardless it will be a long summer for these tough looking wheat fields.  If you need straw I can understand leaving it.  From the cash cropper point of view with the price of straw at 4-5 cents in the windrow there is really only one choice.  It is May 13.  Plant another crop.