Author Archives: Derek Porter

Effects of an Early Season Frost – Derek Porter

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Effects of an Early Season Frost


With temperatures dipping down to the freezing mark and lower Friday night to early Saturday, I thought it would be good to cover the potential effects of a frost on this 2020 crop. Both corn and soybeans should be able to handle a light version of a frost without too many ill effects. I consider a light frost to consist of temperatures ranging from 30-32 degrees for 1-2 hours. It is possible in this scenario for corn growth to be damaged but if the plant is small (v1-V2) it should make a full recovery due to the growing point still being below ground. Soybeans can usually handle a frost better than corn if both are emerged. A light frost could damage the first true leaves of a soybean but likely not damage the soybean cotyledons. Remember the cotyledons on a soybean plant serve as the growing point.

If temperatures stay in that 30-32 degree range for a prolonged period of time (3-4 hours or longer) or a hard freeze occurs, this is where the real threat could lie. With our ground being as wet as it is in central Illinois, I would not expect a hard freeze to affect anything that is not already emerged. However, dry soil will allow a freeze to go deeper. If you are in an area with dry soils, a prolonged hard freeze could be an issue if corn sprouts are within ½” of the surface. Soybeans in this scenario should fare much better. The soybean cotyledons and hypocotyl are much tougher and resilient than a young corn seedling. Any emerged corn during a hard freeze will likely be burnt to the ground but if the corn has not reached that v4 growth stage, I would suspect it to make a full recovery. Emerged soybeans during a hard freeze should survive if the cotyledons are not permanently damaged.

You will be able to tell if corn has been hit with a frost within the first 24 hours. Corn will turn dark green then will wilt and turn pale. Soybeans will start to show damage within the first 24-48 hours after a frost, but it will take up to five days before any real assessment of the crop can be made. If new growth in soybeans has not occurred within 7-10 days after a hard frost, then decisions will need to be made for replant. For any wheat crop, I would wait for 5 days then go split some stems and examine the seed heads for damage.

Our best friend for dealing with a frost would be for the winds to pick up and cloudy conditions to occur. If it stays clear and still, this is when a frost would likely hit. Hopefully, we can get through this weekend without too much damage and continue onward with the 2020 crop. Stay safe and stay healthy!



Illinois Sales Manager


Crop Progress in Central Illinois – Derek Porter

What a difference last week made in the planting progress here in Central Illinois and across many areas of the corn belt. Much of the corn in my area has been planted with a slug of beans being put in the ground much of last week through this week. Unfortunately, there are still areas experiencing wet conditions. I talked to one guy out in Ohio that’s still experiencing wet conditions and it sounded like there was a strong possibility for him to take prevent plant on all his corn acres and if conditions don’t improve, beans might not be planted either. Driving around central Illinois, I would say the condition of the corn crop has improved as we’ve dried things out but there are plenty of fields that are still riding the struggle bus compared to what we normally would expect this time of year in central Illinois. Some corn that is V3 and earlier is trying to establish its nodal root system which might cause yellowing in some fields particularly ones that have been waterlogged and compacted. Soil microbes are also starting to ramp up as conditions dry out and are tying up some of the nitrogen, sulfur, and other nutrients in the soil in order to break down old crop residues. This will cause yellowing in both corn and soybeans and is often referred to as the carbon penalty. Any yellowing seen in corn early on is likely to limit top end yield potential particularly in hybrids that flex in girth. In soybeans, this yellowing will likely go away once the soybean starts to make its own nitrogen which is at the V4 stage and shouldn’t limit yield potential a whole lot. A good way to manage this carbon penalty is to apply some nitrogen either broadcast or with your planter along with some sulfur. I had one grower apply some liquid UAN with some thiosulfate out the back of his planter and he saw a pretty good response in the early growth of his corn.

Speaking of early growth, phosphate-based starter fertilizer’s such as our Crop Choice® 3-18-18-1 or 9-18-9-1 that have a high concentration of phosphorus, push energy production and ultimately growth in the plant. Even if corn was planted late this year, I still expect to see a positive yield response if you used a phosphate-based starter fertilizer such as our Crop Choice blends. The positive yield response could even be as much or more than is typically seen when starter fertilizer is applied earlier in the season. This is due to the accelerated growth that should lead to earlier pollination and a longer grain fill period. This in turn will give about a week more of grain fill leading to higher kernel weight which will be the key to high yields with late planted corn. Usually lack of starch accumulation in the kernels due to a shortened ear fill window is why corn doesn’t yield quite as well when it’s planted late.  

I’m also seeing a lot of sulfur and zinc deficiencies throughout the area and a foliar feed of these nutrients with your post emerge herbicides might be warranted. Our Foliar Opp® contains both sulfur and zinc plus other micronutrients and our Max72-SRN® contains sulfur but can be blended with zinc and other micronutrients as needed. We’ve seen both products add 5-10 bushels in corn when combined with our Sugar E-Boost®. With cash corn at $4.50 here in central Illinois, it only takes 2 bushels of corn to pay for this application.

I’m also seeing good performance out of our Landoil® and Soil Boost spray adjuvants. Once again both adjuvants are proving to be safe on the crop with very little herbicide response being observed in fields that had a full label rate of herbicide applied to them.

I hope things are looking better on your operation as we progress through this tough growing season. If you have any questions you can call our office or contact myself or other Soil Service salesman in your area.


Derek Porter

Sales Manager



Crop response of running UAN with thiosulfate on the planter.

Crop response of using a phosphate based starter (3-18-18-1 on the left) gives a rapid growth response that accelerates corn growth by 1 week.

Corn yellowing due to the carbon penalty.

Sulfur deficiency on corn appears as yellow stripping between the veins. Zinc and other micronutrients such as manganese can look similar.      


Landoil and Soil Boost Extreme did an outstanding job controlling weeds and provided excellent crop safety. 


Assessing Corn Emergence – Derek Porter

I spent last week out in the field assessing corn emergence. The warm weather we finally received last week really helped corn jump out of the ground. However, uneven emergence due to the cool wet conditions over the last 2 weeks was evident in most fields I was in. Cool wet conditions while the corn is trying to germinate can cause the seeds to rot, failure of the radicle root to emerge, the mesocotyl to corkscrew, or the plant to leaf out underground. I saw all these symptoms in the fields I walked but none of these symptoms appeared to be severe enough to force a replant.

 When assessing corn emergence and seedling health in your field, first check the corn seed for firmness by squeezing it with your fingers. The corn seed should be firm to the touch and not mushy. A mushy seed likely means a rot has set in and emergence is likely not going to take place. If the radical root and mesocotyl have emerged, these should be creamy white in color and the mesocotyl and coleoptile should be intact. The mesocotyl is the portion of the seedling that pushes the coleoptile (the portion that contains the first true leaves) to the surface. If either the mesocotyl or coleoptile are severed, this ensures death of the seedling. If both the mesocotyl and coleoptile are damaged, the plant could still survive and emerge. It’s likely this year to see some mesocotyl corkscrewing or leafing out underground before the plant emerges. From what I’ve seen, a combination of surface crusting along with cool soil temps and wet conditions are the root cause for this. When conditions are cool & wet, damage to the cell membranes of the seedling disrupt normal function and energy transfer within the seedling causing the leaves to prematurely emerge or mesocotyl to corkscrew. If the seed imbibes (takes up) cold water within the first 24-36 hours, damage to the membranes within the seed could occur preventing the radical root from emerging and the seed not to germinate at all. I saw this be the case where water had stood for a few days. Seedling injury could also be the result of herbicides that leach into the seed zone shortly after planting. Mesocotyl corkscrewing and leafing out underground are the common symptoms of herbicide injury during germination and emergence. Typically the herbicides that cause this are the growth regulators (2,4-D & Dicamba) or the group 15’s (acetochlor, metolachlor). If used at high enough rates or if the product does not contain a safener, injury could occur if heavy rain pushes the herbicide into the seed trench and cool conditions prevail preventing metabolism of the herbicide. An open seed trench while the herbicide is being applied is a great way for herbicide injury to expose itself. I have not seen any injury from herbicides yet this year but with the amount of rain most have received accompanied with cool conditions and the potential that some fields were planted wetter than ideal means it could show up this year.

Unless water has stood over a field for an extended period (1 week or longer) it appears that most corn is emerging just fine with the expectation that’s some of it is uneven. Unfortunately, many around my area received substantial rain over the weekend with more rain in the forecast for this week. Try to stay positive and remember to always stay safe!


1:Picture showing the mesocotyl and coleoptile of a corn seeding

2:The seed imbibed cold water shortly after planting forcing the radical to abort failed germination

3:This plant leafed out underground due to the cool wet weather and surface crusting

Delayed Planting- Should You Switch to an Earlier Maturing Corn Hybrid?

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The beginning of May finds most of the Midwest lagging behind in corn planting as wet weather continues to inundate much of the area. Even though planting is behind our normal progress, it’s important not to panic and make drastic decisions based on emotion. One of the common mistakes that’s made when planting is delayed is changing from a full season variety corn and an early season variety. This change occurs most likely to the worry of not having the corn black layer by the first killing frost.

While a switch in maturity might ultimately be necessary, it should not be warranted this early in the season. Research done by Purdue and Ohio State investigated the effects of delayed planting in corn. This research found that when planting was delayed into May, corn hybrids adjust to this delayed planting. Corn reaches maturity by accumulating a certain amount of heat units called growing degree days (GDD). When the calendar reaches May 1st,GDD’s for corn to reach maturity decreases by 6.8 GDD’s per day. So a corn hybrid requiring 2700 GDD to mature and planted on May 30th would require approximately 2496 GDD’s to reach maturity compared to if planting had taken place on April 30th. With this lower GDD requirement, a full season variety should be able to reach full maturity before the first typical killing freeze even if it’s planted towards the latter part of May in the Midwest. Usually, switching to an earlier maturing hybrid should not take place unless planting is delayed till the very end of May and into June.

It would be wise however to work with your seed supplier in advance and ask about potentially switching maturities before the time comes due to potential shortages in supply. Keep in mind that a full season hybrid can often times have a yield advantage over a shorter season variety. Switching to an earlier maturing hybrid can be risky due to a lack of heat and disease tolerance if its planted outside of its normal area. While planting date is one key to good yielding corn, always remember that timely rains and moderate temperatures in July and August can have an even more dramatic impact on yield. Research has found that corn planting delayed until May 15th can still provide 95% of optimum yield and planting delayed until May 20th provides 91% of optimum yield. So while the weather refuses to cooperate, it’s important to not get discouraged and over react. There is still a lot of hope for the 2019 growing season.


Spring Anhydrous Ammonia

It’s hard to believe we’ve already turned the calendar to the month of April, especially when one looks around and sees the small amount of field work that’s taken place up to this point across much of the corn belt. If I had to guess, I would say about 50% of the anhydrous ammonia (NH3) has been applied around central Illinois which lags where we typically are at this point. Applying NH3 in the spring can be a risky business to the health and establishment of a corn crop, especially when application is within 1 week of planting. The reason is NH3 acts as a strong desiccant to the young corn seedling by sucking water from seedling roots and tissue. The result is a burning of the root or plant tissue leading to uneven emergence and a stunted sick looking crop. Most injury occurs when soil conditions are less than ideal and when little to no rain (less then 1 inch) occurs after application. When NH3 is applied it starts to rapidly convert from ammonia (NH3) to a more stable safe ammonium (NH4) form of nitrogen. Ideally waiting 1 month or better gives the best odds of this conversion fully taking place and not causing injury to the crop but waiting that long is likely not an option this spring with some applications possibly occurring the day of planting. So, what can a grower do to prevent NH3 injury? Following these guidelines can help especially if your NH3 has yet to be applied.

Focus on the spacing between the injection point and where the seed is placed. Leaving enough distance between the injection point of application and where the seed is placed will be key this spring. Free NH3 within the seed zone or when roots move into a zone of free NH3 can lead to plant injury. A good solution if the grower is equipped with GPS on his planter and applicator is to move the planter off the NH3 band by 4-6 inches. Doing this insures the seed is far enough from the NH3 band yet still close enough to take up nitrogen when the time comes. If a grower plants off the band 4-6 inches, planting can safely take place the day of NH3 application. If a grower is not equipped with GPS, applying NH3 at an angle or planting at an angle relative to an NH3 band is the next best alternative. This insures that at least some of the corn seedlings are far enough away from the NH3 band instead of all of them being directly over the band. I would still advise a grower wait as long as they can (ideally 1 week or better) after the NH3 application before doing this.

Make sure NH3 application is occurring at the proper depth. In heavier type soils (CEC 12-15 and greater) it might still be possible to plant over a spring applied NH3 knife track but depth of the NH3 application will be highly important. Applying at depths of 6-8 inches is a good rule to live by. The lighter the soil the closer to 8 inches you need to be. When NH3 is applied it typically stays in a concentrated area 2-6 inches in diameter from the point of injection. The drier the conditions and the lighter the soil the further the ammonia will move from the point of injection. In higher soil moisture conditions, particularly in heavier clay type soils, NH3 stays more concentrated to the point of injection. Therefore, an inch of rain after application usually helps mitigate the risk of injury. This concentrated band makes uniformity of depth during application extremely important. An application too shallow (4 inches) can put the seed within 2 inches of the NH3 band and if the concentration zone expands, there is a strong likelihood the seed is in contact with free ammonia. Keep in mind that when application is done in wetter conditions, staying at a deeper depth could be challenging due to how hard the toolbar might pull. Also making sure the bar is running level and all cylinders are set properly is key to applying at a uniform depth. In fields with a lot of hills and rough terrain, applying at a uniform depth could also be a problem and needs to be taken into consideration at planting.

Make sure the knife track is closed properly. It will be important to monitor that proper sealing is taking place when NH3 is being applied. With above average soil moisture being the norm across most of the corn belt, smearing of the sidewall can easily lead to failure of closing the knife track. This can lead to NH3 diffusing up into the seed zone and even worse all the way out of the ground into the atmosphere. Checking for proper closing can be as simple as looking for gas over the knife track or getting a strong whiff ammonia as you work through the field.

Summary. My advice to growers this spring is to plant off the knife track or apply at an angle if NH3 is going to be applied within 2 weeks of planting. The heavier the soil (CEC >12-15) and the greater the moisture content, it’s possible to apply over the NH3 band if 1 week has passed and a uniform depth of greater than 6 inches is achieved. Also be very vigilant of proper sealing over the NH3 knife track. Shallow tillage could be done immediately after application baring the NH3 was applied at the proper depth and conditions are not too dry to allow NH3 to escape the surface. Keep in mind that there are other forms of N out there, such as UAN or Urea, that could be used as a replacement for NH3.

Uneven emergence due to NH3 injury







NH3 damage appears burning at the roots


Derek Porter