Wheat Conditions - On Staurday night / Sunday morning we again dipped below 32 degrees for about 4 to 6 hours.  Will this latest freeze impact the wheat crop?  I really would doubt it.  In the Garden City area the wheat is in the 1st to 2nd node growth stage.  At that point freezing temperature have the potential to cause damage but we have a few factors going for us.  We only got that cold for a short time period and the ground temperature was over 50 degrees and it provided some protection as well.  The following day (Sunday) we rebounded with warm temperatures so it is not the typically scenario to expect anything more than minor damage.  It will take at least a week to evaluate but at this point I would say there is no damage.  We are not far enough along on the crop where the head damage will manifest itself later (meaning the plants look good but the heads are sterile).  That can occur from the boot stage on.  The flowering parts have not developed in the heads yet.  The biggest concern for this wheat crop continues to be the dry conditions.  We continue to live from shower to shower with no soil moisture profile beneath it. 

Alfalfa - Both alfalfa weevils and aphids have reached threshold for treatments on numerous fields south of Garden City and the sandhills south of Deerfield and Lakin.  Overall it does appear to be a lighter than normal year for weevil but part of this may be just a dealy in what is to come.  Alfalfa weevil development is driven by growing degree units and we are far behind normal for this time of year.  I would expect the first cutting of alfalfa is at least a week behind riight now and if you were treating for weevils this week I would still likely use full rates of Pyrethroids.  If aphids are present in significant numbers add 4 oz Lorsban to the Pyrethroid.

 

Corn - The first corn to get planted went in about 2 weeks ago today.  Those fields are just now starting to emerge.  Current soil temperature is 52 degrees and I would expect that we'll see corn going in today emerge in about 8 days.  At this point there are no pest problems with the crop.

 

    

After weather service predicted lows of 34 degrees for Garden City on the morning of April 18th, much colder lows were encountered.  Late in the day on April 17th the skies cleared and the temperature plunged.  According to accuweather it only reached a low of 31 degrees in Garden City.  My thermometer showed 28 degrees.  Lows of 28 degrees were reported in Liberal, KS and lows of 24 degrees were recorded in Guymon, OK. 

Will these temperatures damage the wheat?

We've all been through this many times before and about all you can do immediately after a freeze is report the lows and evaluate the growth stage of the wheat.  In Garden City most of the wheat is at 1st node.  The growing point on the wheat is about 1 to 2 inches out of the crown.  In Guymon most of the wheat is at 2nd node.  Damage to wheat is a function of growth stage time and temperature.  In past years where late freezes have been an issue most occured at this same time or even a little earlier.  The most devastating ones occured for more than one night in a row.  The daytime highs between these nightly freezes were typically colder than what we went through today.  It will take at least a full week to evaluate the extent of damage if any.  Immediately after a freeze lower stem splits would already be visable.  I noticed none today in the Liberal area.  If head death occured it will take at least a week to evaluate.  The head can be found by splitting stems above the highest node.  After a week these heads will start to turn brown and shrivel.  A few days after that the whorls on dead tillers will start to push a dead leaf.

I tend to be a glass half full kind of person but just based on what we know today I would doubt very much that the wheat crop was damaged north of Liberal with the jury still out on the wheat in the Oklahoma panhandle.            

There is a freeze warning for much of Oklahoma and into north central Texas for the early morning of April 14th.  It will also likely freeze across Kansas but the concern will only be for the southern areas where the wheat is much further along.  In Kansas the most advanced wheat is just setting first node and a light freeze will be no threat to this crop.  In southern Oklahoma and Texas the wheat is in boot to partial heading and temperatures as low as 30 degrees can cause significant damage.  The 14 day forecast currently shows no further threats after Sunday night.  

Greenbugs are becomming established in the wheat in the Oklahoma panhandle but still at less than treatable levels.  Revised economic thresholds from KSU would suggest that treatments are warranted when 2 greenbugs per tiller are present on a little over half of the tillers in the field.  This threshold assumes $9.50 / bu wheat with a $9.00 insecticide treatment.

Alfalfa Weevil progression has slowed to a stop over the past week due to the lack of GDU's.  This insect lays it's eggs in alfalfa residue in the fall and the early spring and egg hatch is driven by temperature.  We have not even averaged 50 degrees now for the past 10 days and with the warmer forecast are still likely 10 days from treatments in the Liberal and Guymon area and 14 days from treatments in the Garden City area.

As already mentioned, average temperatures have been below 50 degrees for the past 10 days and if anything, soil temperatures have dropped.  Currently in Liberal the 3" soil temperature is 42 degrees at 10:00 AM.  In Garden City the temperature is also 42 degrees.  In a situation where a grower is looking at 30 days to get their corn crop planted, it might make sense to start early the week of April 14th but if a grower can plant their entire crop in 14 days or less I would wait until late in the week of the 14th or early the week of April 21st.  We should see 50 degrees at that point based on the warmer forecast.    

We finally have some rain in the forecast.  As of this writing the first of our chances went east of Garden City, Liberal  and Guymon with only very low amounts in the western areas.  Most of the wheat south of Garden City is just starting to joint with the earliest planted wheat in the Oklahoma panhandle putting on first node now.  We have some mildly concerning temperatures in the forecast with a light freeze called for on April 16th and 17th.  Right now forecasters are calling for lows of 30 degrees both nights in Garden City and a low of 30 degrees as far south as Guymon for the night of April 16th.  If it gets no colder than that, the wheat should be fine.  If it gets down to the mid 20's or below there could be some problems.  We are still not seeing any significant disease pressure in the wheat.  Leaf Rust is being reported in north central Oklahoma and extreme south central Kansas and we'll likely see the start of infestations here over the next few weeks.  Greenbugs are starting to become established in fields at very low levels in the Oklahoma panhandle.  At this point we are still not seeing any in Kansas. 

The alfalfa is off to a good start with southern fields having as much as 6" to 8" of growth.  Temperatures in the high 20's will have no negative impact on the crop and we should see normal to a little earlier than normal 1st cutting dates.  Because of the spread between alfalfa prices and corn prices we'll see significant acres of alfalfa come out after 1st cutting and go to corn.  We are seeing about 30% of our irrigated alfalfa being taken out this year.  Alfalfa weevil numbers continue to increase and we will likely see the 1st insecticide treatments applied in the south in about 7 days.  We are probably closer to 14 days out on the alfalfa in the Garden City area.  In many cases we have also had pea aphids and cow pea aphids invade these fields as well.  If a Pyrethroid Insecticide is going to be used for weevil control and it does not contain Lorsban it is a good idea to add a low rate of Lorsban to the application to pick up the aphids that are present in the field.  4 to 8 oz of Lorsban will be sufficient. 

Corn Planting Dates - Current soil temperatures are around 46 degrees in the south and 44 degrees in Garden City on pre watered strip till ground.  We really need closer to 50 degrees with a warming trend predicted.  I really don't think it makes sense to start the corn until the middle of the week of April 14th in the panhandle and late in the week of the 14th at Garden City.