2017 Starter Trials Crop/Weed Developments  05/25/17 12:16:58 PM

NEXT WEDNESDAY--Mynard Plot Tour—The process will be much as it has been in the previous years.  We have the tours RAIN OR SHINE—If raining--we will gather in our seed building—If the sun is shining--at our plot on the West side of Mynard Nebraska—1 mile South of our plant—1/4 west on Mynard Road OR 1-1/4 mile West of HWY 75 on Mynard Road—South Side of the Road.   The tours will last no longer than 1.5 hours and address any current agronomic issues as well as allow the attendees to monitor developmental progress of Asgrow and Dekalb genetics throughout the growing season.  View the current genetic lineup as well as population trials, planting speed trials, fungicide and insecticide seed treatment comparisons, biological seed treatments, the affects of starter fertilizers and more!   
2017 WBI Summer Dates
Date                            Location                      Time                            Guest Speakers/Topic
Wednesday  May 31th Mynard Plot                9-10:30 a.m.                Tim Mundorf_Midwest Labs—Post-emergence
Fertility Observations
Post-emergence Weed Control Options, Planting Re-Cap
                       
Tuesday June 13th       Mynard Plot                9-10:30 a.m.   
Tuesday June 27th       Mynard Plot                9-10:30 a.m.               
Tuesday July 11th        Mynard Plot                9-10:30 a.m.
Tuesday July 25th        Mynard Plot                9-10:30 a.m.
August 2nd-6th              Springfield                                                      Sarpy Co. Fair
Tuesday August 8th     Mynard Plot                9-10:30 a.m.
August 9th-12th            Cass Co. Fairgrounds                                      Cass Co. Fair
Tuesday August 22nd  Mynard Plot                9-10:30 a.m.                Corn Breeder/Corn Lineup
                                                                                                            Soybean Breeder/Soybean Lineup
Tuesday August 29th   Cass Co. Fairgrounds                                      Late Summer Clinic
BRING A FRIEND AND WE WILL SEE YOU NEXT WEDNESDAY!!
2017 CORN STARTER FERTILIZER TRIAL --As we have stated previously,  it is academically documented from research dating back to the 1950's that banded application of immobile nutrients such as P and K near the seed at planting can be much more agronomically efficient than a broadcast application over the soil surface when considering corn stand establishment. Research conducted at Purdue University by Barger indicates this is a function of the amount of soil the roots must explore to obtain adequate amounts of the immobile nutrients such as phosphorus, potassium and zinc to germinate and effectively grow. Starter fertilizers have a long pedigree of what it can do for the emergence and development of a uniform stand. This too, can be affected by your soil type, soil moisture content, as well as soil temperature at planting.
For corn and soybean production, Midwest Laboratories, as well as WBI, would suggest that the optimum phosphorus P1 level test should be 25 ppm or above, zinc at 2.0 ppm, and the K levels should be around 200ppm. How many fields fit these criteria? What can be done to maintain these levels??
We continually evaluate our fertility levels in the soil and over time both academics and producers using starter fertilizer agree that banding or in furrow starter fertilizers plus additives can pay off considerably. BUT, What happens under various soils, fertility levels, etc. This is the question we ask every year about this time.
SO, we started this trial 4 years ago at the following site with these fertility levels—Current data shows an average 12 bushel increase in yield on this site using a starter on some sort. 
 
FOR 2017, the treatment list includes:
 
 
Our treatment list included the following
 
1.  5 gal of Optistart Pro--9-18-6-2Sulfur 0.5 Zn-0.05 MN with Avail
2.  5 gal of Optistart Pro--9-18-6-2Sulfur 0.5 Zn-0.05 MN with Avail + 3.4 oz of Capture LFR
3. 5 gal of Optistart Pro--9-18-6-2Sulfur 0.5 Zn-0.05 MN with Avail + 3.4 oz of Capture LFR  + 3.6 oz. of Xanthion.
4.  5 gal of Optistart Pro--9-18-6-2Sulfur 0.5 Zn-0.05 MN with Avail + 3.4 oz of Capture LFR + 10 oz of Optify Stretch
 
That being said, what are the additional components to the base treatments??
OPTISTART PRO is a complete fertilizer mix with an Avail premix
AVAIL inhibits phosphate fixation throughout the growing season.
CAPTURE LFR is an insecticide which controls seedling pest such as wireworm, white grubs, armyworn and corn rootworm.
XANTHION is a fungicide that can enhance root development, help control soil borne diseases, and improve seedling health.
OPTIFY STRETCH is a broad spectrum biostimulant that includes a PGR for use in corn and other crops that improves a plant’s ability to withstand stress, increase early season vigor and more efficient nutrient and water uptake
 
 
                 
Baseline Soil Test Results            
Tested March  2017   What does this mean??        
Ph 5.2 Low-- In need of lime        
Organic Matter 3.1% Average percentage range for this area
C.E.C. 18.0 Most soils range between 5 at 35 meq/100g        
P1 Test 35 ppm Excessively high--optimum range is 25-30 ppm    
P2 Test 39 ppm Low--Normally should be 2x the P1 level
Sulfur 23 ppm Excessive for this soil type and CEC      
Potassium         230 ppm High--Optimum range between 150-200 ppm.  
Zinc 1.6 ppm Average--1.5-2.0 ppm is normally adequate    
                           
 
WHAT ABOUT SOYBEANS—AND A STARTER??  Not very often to you hear anything regarding soybean and starter fertilizer.  However, given the yield levels of recent years, we will consider again the nutritional needs of soybeans and their ability to get ENOUGH fertility out of the mineralized credits in the soil.  Treat soybeans as a crop and not just a rotation from a fertility level.  Consider this:
 
Soybean Bushels/Acre   90 85 80 75 70 65 60 55 50 45 40
  Used for                      
Nitrogen (N) Grain 342 323 304 285 266 247 228 209 190 171 152
  Stover 99 93.5 88 82.5 77 71.5 66 60.5 55 49.5 44
  Total Use 441 416.5 392 367.5 343 318.5 294 269.5 245 220.5 196
                         
Phosphate (P2O5) Grain 76.5 72.25 68 63.75 59.5 55.25 51 46.75 42.5 38.25 34
  Stover 22.5 21.25 20 18.75 17.5 16.25 15 13.75 12.5 11.25 10
  Total Use 99 93.5 88 82.5 77 71.5 66 60.5 55 49.5 44
                         
Potassium (K2O) Grain 117 110.5 104 97.5 91 84.5 78 71.5 65 58.5 52
  Stover 90 85 80 75 70 65 60 55 50 45 40
  Total Use 207 195.5 184 172.5 161 149.5 138 126.5 115 103.5 92
                         
Sulfur (S) Grain 16.2 15.3 14.4 13.5 12.6 11.7 10.8 9.9 9 8.1 7.2
  Stover 15.3 14.45 13.6 12.75 11.9 11.05 10.2 9.35 8.5 7.65 6.8
  Total Use 31.5 29.75 28 26.25 24.5 22.75 21 19.25 17.5 15.75 14
                         
Zinc (Zn) Grain 0.090 0.085 0.080 0.075 0.070 0.065 0.060 0.055 0.050 0.045 0.040
  Stover 0.30 0.28 0.27 0.25 0.23 0.22 0.20 0.18 0.17 0.15 0.13
  Total Use 0.39 0.37 0.35 0.32 0.30 0.28 0.26 0.24 0.22 0.19 0.17
If you look at Phosphate alone and your yield level has gone from 50 bu./acre to 65 bu./acre, your need for phosphate has 12.75 lbs/acre in the grain needs alone.  This doesn’t seem like a lot, however,  Phosphate/Phosphorus is tightly held in the soil profile and so it would make more sense to have to the additional P2O5 needs close to the root system for plant use—Right?
SO, we ran 2.5 gal of Optistart Pro--9-18-6-2Sulfur 0.5 Zn-0.05 MN with Avail + 3.6 oz. of Xanthion in the furrow with soybeans at Planting.  We have 4 locations where we did this—one of which has 8 replications.  AGAIN—STAY TUNED
 
GET READY TO BE AMAZED—With all of the current moisture in the soil profile, the prospect for consistent warm weather, and the corn finally developing seminal roots that are now reaching the fertility zone, the corn is ready to grow fast.   When corn grows fast, here are a number of things that occur.
 
1)   Yellow streaked corn continues to be an issue in many areas.   A very quick growth spurt can temporarily cause yellow streaks between the veins of the leaves and/or yellow the whorl.  Under quick growth conditions, the plant cannot keep up with the chlorophyll production demand of the plant causing the yellowing to occur.   The larger issue of yellow corn is a product of the weather conditions of the past weeks.
2)  Rapid Growth Syndrome--What appears to have the appearance of a herbicide reaction, is actually referred to as Rapid Growth Syndrome.  Characteristics of RGS occur after plants have emerged normally.  Following a period of relatively stressful growth, plants receive a good amount of rain or irrigation and both day and night time temperatures are high - (90+ day, 80+ night).  Under these situations, the plants are exhibiting rapid cell elongation and division.  When this becomes severe, some of the plants leaves do not have an opportunity to unfold properly.  Usually, there is a relatively small percentage of plants involved (less than 20%).  This syndrome can be distinguished from other injury like herbicide in that the condition develops well after emergence and the lower leaves are not affected.  Once temperatures become more normal, this condition will stop and leaves will begin to unfurl.  This may take 4 - 5 days. When plants do unfurl, growers will notice “yellow flash” as the newly exposed leaf tissue has not begun to produce any chlorophyll.  Once exposed to sunlight, these “yellow flash” leaves will return to normal within 2 - 3 days and plant growth should return to normal with no long term affects.
3) If the corn stood in saturated (above field capacity) soils for several days, we are likely to see light green to yellow plants in areas of the field that are lower, or not as well drained. Lower leaves may be turning brown and drying up. This should be a temporary condition, without long term negative effects on the crop.
The uptake of plant nutrients is an energy requiring process, much of which is provided by oxygen. In situations where soil pores are filled with water and oxygen is displaced, uptake capacity of the roots is limited. Once the soil drains, and air can get back into the soil pores, and with the warm weather we are now experiencing, this should be a short term problem.
 
4)  What becomes of the nitrate in these situations? Nitrate, which is the plant available form of nitrogen, and also water soluble, is subject to leaching, or denitrification in saturated conditions. How far nitrate will leach is dependent largely by how far down the water moves. One inch of rain on a dry silt loam soil will penetrate about 4-6”. Additional water can move nitrate down further and out of the root zone of small corn plants. However, in heavier soils, especially with high clay content in the subsoil, leaching is reduced due to smaller pore spaces, and less mass flow through the profile. As roots grow down, they can get to the nitrate, providing it doesn’t leach below about 4’. Remember too, that as water evaporates from the soil, water moves upward and can take nitrate with it, bringing some back to upper levels of the soil profile.
 
5) Denitrification occurs when anaerobic (require little or no oxygen) bacteria increase in activity and break down the nitrate molecule to gaseous forms of nitrogen, which in turn is lost to the atmosphere. This can occur if soils are saturated for at least two days, at temperatures above 60 degrees. Losses can be 2 lbs./acre/day or more as reported by the University of Nebraska. Another corn belt study cites losses of 4-5% per day of saturation. In this same study, saturated soils for 5-6 days cost about 10-20 bu/acre in lost corn yield. Again, as the water drains and the soil returns to field capacity (which is defined as the amount of water in the soil remaining after having been saturated, and after free drainage has stopped), the activity of the anaerobic bacteria will decline and denitrification will cease. So, unless water is “ponded” for an extended period of time, denitrification should be short lived.
 
Should more nitrogen be applied? Assuming that adequate rates of nitrogen fertilizer was applied to begin with, the answer in most cases will be “no”. As mentioned above, if an area is slow to return to normal color, and the area is large enough to make side-dressing feasible, then applying an additional 40 lbs could be justified.  If side dressing additional amounts of UAN was part of your original management strategy, adding another 10-15 lbs in light of the wet weather conditions this spring is probably not a bad idea.
  
Corn in Eastern Nebraska on average transpires between 25-28” of water through the plants during the growing season.  Most corn in Cass County is currently around V4 to V6 leaf stage (3-5 collars).   Corn uses water at an amazing rate when undergoing a fast growth spurt.  We now are using between 0.05”and 0.10” of moisture transpired through the plants each day. The plant roots are in the top 6-8” of the soil profile and a typical corn plant can root up to 4 feet deep. Forty percent of water absorption occurs within the top 12”,  30% in the second foot, 20% in the third foot, and 10% in the fourth foot of the soil profile. Deep within the whorl of the plant, corn is just beginning the time of ear initiation and development of the tassel. In other words, components of yield (kernels per ear, ears per acre) are already determined and are subject to water stress within the plant.  The following table demonstrates the amount of water used per day.
 
Growth Stage                                      Inches Water Use/Day
1-4 leaf                                                            .02 - .05
5-8 leaf                                                            .05 - .10
8-10 leaf                                                          .10 - .15
11-14 leaf                                                        .15 - .20
14-18 leaf                                                        .20 - .25
19 leaf - blister                                                .25 - .30
Milk - soft dough                                            .20 - .25
Hard dough - early dent                                 .15 - .20
Mid - full dent                                                .10 - .15
 
Many of the soybeans are in the unifoliate (V1) stage with the 1st trifoliate emerging and the 2nd and 3rd trifoliate visible.  Bean Leaf Beetles have begun to feed with the emerging crop.  Remember, that once the first trifoliate has developed, the plant can withstand up to 50-60% of vegetative feeding/tissue loss from bean leaf beetle feeding before a treatment is economically justified.   This amount of feeding can have an approximate yield loss of 5%, which would easily pay for the cost of treatment. I have not seen any injury severe enough to require a treatment.
 
Soybeans on average transpire between 22-25” inches of water through the plants each year. They use 65% of total water use during the reproductive stage (flowering/podding) of development  They are beginning the second node development (V2) and soon the 4th and 5th trifoliate will emerge.  Nitrogen-fixation (nodulation) has begun with lateral root development occurring in the top 6 inches of the soil profile.  Soybean root development can reach 5 and 6 foot depths, but like corn, the largest concentration of root development and water uptake occurs within the top 2 feet of the soil profile. The following table demonstrates the amount of water used per day.
 
Growth Stage                                      Inches Water Use/Day
Germination/Emergence                                 .01 - .15
Vegetative Growth                                         .15 - .20
Flowering                                                        .25 - .30
Pod Development                                           .20 - .25
Seed Fill                                                          .15 - .20
Maturation                                                      .05 - .10                                  
 
Post-emergence Weed Control----Weeds will also grow fast in weather like this!!  Remember last year’s marestail issues?  Extended weed control along with a Tank-Mix partner will be needed in many of the Roundup Ready Corn and Soybean fields this year.  Cool, wet weather during early establishment and growth has reduced many stands in Eastern Nebraska.  Thin stands give weeds more of an opportunity to become established and compete with the soybeans and corn for soil moisture, nutrients, and sunlight.  Given the spring we have had, both crops do not need any more help in falling behind in development due to weed pressure.  Consider the following when spraying your Roundup Ready crops post-emergence.
 
 
Weed Height (inches)             Roundup  WeatherMAX Use Rate (oz/acre)
            1-4                                                                   22
            4-8                                                                   32
            8-12                                                                 40
            12-18                                                               48
            18 and beyond                                                56+
 
  • Always use the higher rate if in doubt on weed height of the key weed species trying to control
  • Spray when weeds are actively growing and not under stress (cold/drought or extreme heat)
  • Use Ammonium sulfate at 17 lbs. Per 100 gallons of spray solution
  • Can substitute ammonium sulfate with an additional 3 oz/acre of Roundup WeatherMAX if desired
  • Do not use 28% nitrogen or thiosulfate as substitutes for ammonium sulfate
 
Ammonium sulfate offers water buffering effects and also helps the herbicide droplet penetrate through the leaf surface of the weeds, especially broadleaves.
 
 
 
 
John W. McNamara
Agronomist
Wiles Bros. Inc.
606 Wiles Road
Plattsmouth NE. 68048
(402) 298-8550--Office
(402) 499-3870--Cell
(402) 298-7174--Fax
 
 
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