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Ohio State University Extension


C.O.R.N. Newsletter 2011-16

Dates Covered: 
June 1, 2011 - June 6, 2011
Glen Arnold

The Weather Outlook is as Follows

The outlook is as follows:

The greatest risk of rainfall the next 3 weeks is in the north and the least in the south for Ohio. A hot high pressure will anchor over the southern and south-central U.S. this summer over their drought area. A ring of fire of storms will rotate around this high pressure from time-to-time.

The most vulnerable area for complexes of heavy rain and storms will be in northern Ohio near the jet stream in the next 3-4 weeks. We can not rule out some flash floods in the next month or so in the northern part of the state. Not everyone will see these storms but the heaviest will be in the north and scattered.

In the short-term, hot and drier weather will be the dominate pattern this week.

May 31-June 5 - Temperatures 5-10F above normal with maximum temperatures mostly in the 80s and lower 90s and lows in the 60s to near 70 except slightly cooler near Lake Erie. Rainfall generally will be below normal with scattered rainfall activity. Heaviest rainfall will be in the north and scattered totals over an inch possible there.

June 6-12 - Temperatures about 5F above normal with near to below normal rainfall. Rainfall will likely increase late in the week as the ring of fire of storms begins to setup.

June 13-19 - Temperatures near normal with rainfall near to possibly slightly above normal.

Wheat Update: Diseases and Crop Development as the Weather Changes

After raining almost every day during the last few weeks, since late last week we have now had three or four days without rain in some areas of the state. The forecast is for relatively drier, warmer conditions over the next two weeks which will affect both disease and crop development. However, the lack of rain does not mean that we are experiencing dry conditions, in fact it has been very humid, and like frequent rainfall, high relative humid also favors the development of wheat diseases, including scab and Stagonospora. After the above-average rainfall we had this spring, there are lots of wet fields out there, contributing to the high relative humidity.

Most of the wheat in the southern half of the state is past the flowering growth stage; wheat in parts of central Ohio flowered over the Memorial Day weekend; and in the north and northwest is now flowering or will flower during this week (the week of May 23). The scab forecasting system is indicating moderate-to-high risk for scab in Northern and Northwestern Ohio for wheat flowering at this time. This risk prediction has essentially been the same since last Saturday, suggesting that conditions have been favorable for scab during the last week or so. Although it has not rained since last Friday or Saturday, we have had enough wet and humid days over the last week to keep the risk for scab moderate-to-high. This was the case in several fields last year where high relative humidity resulted in relatively high scab and vomitoxin levels, even in the absence of frequent rainfall during flowering.

Producers with fields flowering at this time should consider applying either Prosaro, Caramba or Folicur to suppress scab and vomitoxin. Such an application will also provide protection against late development of Stagonospora. Folicur is less effective against scab than Prosaro and Caramba, however, none of the three products will provide 100% scab or vomitoxin reduction. At best you can expect about 50 to 60% suppression. With drier conditions in the forecast, the risk for scab may be reduced for wheat fields flowering late this week or early next week, however, keep reading the C.O.R.N Newsletter for more updates and keep your eyes on your local weather conditions and the scab risk tool to see how things develop.

As the wheat enters the grain fill stage of development, temperatures, especially during the nights, will determine the length of the grain fill period, and consequently, how well the crop yields. Above-average temperatures are forecasted for the next two weeks and this will likely shorten the grain fill period considerably. At temperatures above 85 F, photosynthesis slows down and eventually stops, meaning that the production of materials to fill grain stops. At these same high temperatures, respiration increases, burning up sugars and resulting in lower yield and grain quality. The process of burning up food through respiration at high temperatures without replacing it via photosynthesis is commonly referred to as the wheat crop “shutting down”. So, if the forecast is correct and we do indeed get several hot days over the next few weeks, we can expect a shorter grain fill period and lower yields than in cooler seasons. 

Early-to-mid June Corn Plantings: Yield Expectations

In previous articles we’ve noted that by the end of May, planting delays may result in yield losses as high as 2 bushels per acre per day but that the impact of late planting on yield can be highly variable. Information on the performance of corn planted in June is limited. When planting is delayed beyond June 1, many grain producers switch to soybean because it has generally been regarded as more profitable than late-planted corn.

What can we expect from corn planted for grain in June? Since 2005 we have conducted field studies to compare the agronomic performance of corn planted on “normal” Ohio planting dates in late April and early May with that of corn planted on dates in early-to-mid June. These planting date studies also included hybrid maturity, nitrogen, seeding rate and foliar fungicide treatments but for the purpose of this discussion we will focus on planting date effects. The Ohio Corn Marketing Program provided funds to initiate this research. The studies were performed at OARDC-OSU research farms in southwest, northwest, and northeast Ohio. The hybrids used over this six year period varied depending on experiment but have usually contained transgenic Bt corn borer and rootworm resistance and glyphosate and/or glufosinate herbicide resistance.

Figure 1 summarizes results of 17 experiments in which yields of normal and June planting dates were compared (SC-South Charleston; NW – Northwest; WO-Wooster). Yields of corn planted on June planting dates, averaged across site years, were about 14% less than corn planted on normal planting dates. Yields were greater for corn planted on normal planting dates compared with June dates for 15 site years. However, there was considerable variation in yield differences.

Yield losses ranged from -6% to -43%. Yields were greater for corn planted on June planting dates compared with the normal dates for two site years, WO2005 (+13%) and NW2007 (+3%). The major yield loss for June planted corn at SC2008 (-43%) could be attributed in part to severe stalk lodging caused by strong winds associated with the remnants of  Hurricane Ike ( Sept 14, 2008).  The yield advantage of June planted corn over normal planted corn at Wooster in 2005 could be related to timely, above average rainfall in August (associated with the remnants of Hurricane Katrina). The late planted corn benefited more than the early planted corn from this greater rainfall because it occurred earlier during grain fill in the late planted corn than for the earlier planted corn.

At the NW2007 site, corn planted on the normal date yielded less than June planted corn because it was more severely stressed by early-mid season water deficits than the late planted corn. These results are consistent with what has been noted in previous articles on effects of plantings delays, i.e. grain yields of corn planted as late as early June are strongly influenced by growing conditions during grain fill in August and early September.

Corn planted on late planting dates is often associated with greater stalk lodging than corn planted on normal dates. In this assessment of normal vs. early June planting date effects, % stalk lodging was much greater for June plantings at three site years (2% vs. 81% at SC2006; 16% vs. 52% at WO2006; 62% vs. 17% at SC2008); differences were generally negligible for the other sites. Grain moisture content at harvest for corn planted in early -mid June, averaged across site years, was about 5 to 6 percentage points greater than corn planted on normal planting dates.

It’s important to keep in mind that these comparisons of normal and late planting dates were generally conducted at locations with a history of high yield potential. The fields were characterized by soil fertility levels within the optimal range for corn production and uniform tile drainage. These are conditions which may not always typify late planted on-farm fields.

Figure 1.  Grain yields of corn planted on “normal” Ohio planting dates in April/May vs. early-mid June dates, OSU studies, 2005-2010.

  Figure 1.

More on Switching Hybrid Maturities

Farmers who anticipate planting corn for grain production during early- to mid June should review their hybrid maturities. Much of the following information is taken from "Delayed Planting & Hybrid Maturity Decisions", a Purdue/Ohio State University Extension publication available online at: Table 1 lists the relative hybrid maturity values that should safely mature prior to a fall frost (32 o F) when planted from late May through early June in Ohio. These “safe” hybrid maturities were estimated for the various geographic areas of the state according to the available length of growing season (GDDs) following the planting period, the average date of the first fall frost (32 o F), and adjustments based on hybrid GDD response to delayed planting.

Table 1.  Approximate “safe” relative hybrid maturities for delayed plantings throughout Ohio.  Bolded values indicate hybrid maturities that are earlier than what is commonly grown in that area of the state, otherwise the listed hybrid maturities are within the commonly grown range in each area of Ohio.


Latest “safe” hybrid maturity for planting no later than…

Area of Ohio

May 31

June 7

June 14


CRM Values





































Hybrid CRM (comparative relative maturity) values correspond closely with those used by Pioneer Hi-Bred International, Inc.

A one "day" difference in relative maturity rating usually equals 0.5 percentage point difference in grain moisture content at harvest (Nielsen, 2011). For example, that means there will only be about 2 percentage points difference between a 106-day hybrid and a 110-day hybrid at harvest.

Keep in mind that these estimates of safe hybrid maturities are aimed at achieving grain maturity before the average (50% probability) date of the first “light” fall frost (32 o F) in the fall. Such frost events normally injure corn leaves, but do not kill the whole corn plant. The first fall frost dates generally range from the first through the third weeks of October from northern to southern Ohio. Using the first occurrence of a “light” fall frost (32 o F) rather than a true killing frost (28 o F) adds a bit of a “safeguard” to the estimates of safe hybrid maturities.

Although hybrids with maturities listed in Table 2 should safely mature by their respective dates, they may mature in the fall at a time when conditions are unfavorable for grain drying because of late planting. Selecting earlier maturing hybrids may promote faster dry down but agronomic performance should not be sacrificed. Some shorter season hybrids may not be suitable in terms of their stress tolerance and disease resistance (Nielsen, 2011). Table 2 provides a comparison of grain moisture content at harvest in hybrids ranging from 102 to 113 days relative maturity (days relative maturity for DeKalb hybrids) planted in late April/ early May and in early/mid June.

Table 2.  Effects of planting delays and hybrid maturities on corn grain moisture at harvest (unpublished OSU research, 2009-2010)



Hybrid Maturity (days)


Planting Date







-----% harvest moisture----







S. Charleston 2009 (3)*

Late April/Early May






Early/Mid June











S. Charleston 2010 (3)

Late April/Early May






Early/Mid June











Hoytville 2010 (1)

Late April/Early May






Early/Mid June





* number in parentheses indicates number of studies

For the hybrid maturities shown in Table 2, the 102 day hybrid produced grain yields that were comparable to or higher than the 104, 111, and 113 day hybrids for the June planting dates. Differences in stalk lodging were generally negligible (5% or less) among hybrids. These results are consistent with a study conducted at six Ohio sites in 2005 and 2006 that compared the agronomic performance of six ‘commonly grown’ hybrid maturities with 13 short season hybrids planted in late April/early May and early to mid June. The nineteen corn hybrids represented a range of maturities from 97 to 111 days relative maturity (2180 – 2800 growing degree days). Early planted plots were harvested in mid/late Oct. and the later plantings in late Nov./early December. Results indicated that 100-104 day hybrids are available with yields comparable to hybrids of commonly grown maturities in early and late planting environments. The 100-104 day hybrids showed greater yield potential than the hybrids with maturity ratings less than 100 days. Grain moisture of early hybrids were  3 to 5% lower than commonly grown maturities At test sites with the highest level of stalk lodging, most of the early hybrids showed levels of stalk lodging comparable to those of the commonly grown hybrid maturities.


Although corn for silage responds to timely planting, it is more tolerant of late planting than is corn planted for grain. Silage growers can generally continue to plant adapted hybrid maturities for silage purposes until late June because silage harvest typically occurs several weeks before physiological maturity. Penn State University researchers have reported yields of more than 20 tons/acre with mid-June plantings in some years. Their studies indicate that corn silage can produce reasonable forage yields in many areas, even when planted in late June. Penn state studies have shown that energy levels are reduced in later-planted silage, presumably because of lower starch levels due to reduced grain fill.


Nielsen, R.L. and P.Thomison. 2003. Delayed Planting & Hybrid Maturity Decisions. Purdue Univ. Cooperative Extension Publication AY-312-W. [On-line]. Available at [URL accessed May 31 2011].

Nielsen, R.L. 2011. Update: "Safe" Hybrid Maturities for Delayed Corn Planting in Indiana. Purdue Univ. Cooperative Extension Publication AY-312-W. [On-line]. Available at [URL accessed May 31 2011].

Bean Leaf Beetles on Emerged Soybeans

Reports have come in of large bean leaf beetle densities on soybeans that had been planted in mid-May and have since emerged.  These few emerged soybean fields are serving as a trap crop for those beetles that have been looking for soybeans to feed on; all the beetles are going to those few fields rather than spreading out over a lot of fields.   This situation has been seen in previous years with significant spring rainfall.  These fields could be receiving more feeding injury than normal and should be checked immediately.  If defoliation is over 50% or if the new trifoliate leaves that are emerging are still being fed on, control might be necessary. 

We would point out that any field with an insecticide seed treatment should be relatively free of feeding; these seed treatments usually do a good job of controlling bean leaf beetles. 

Because of the egg laying that is occurring in fields with high beetle numbers, the fields might end up having very high numbers of first generation beetles later in July, much higher numbers than usually seen.  Growers with large numbers of overwintered beetles in their fields now should plan on checking their fields closely in mid-to-late July for the next generation.

How You Can Help the Sun Make Hay When It Shines!

As the sun makes its appearance once again in Ohio, many forage producers are looking forward to making hay. Last week I encouraged patience to wait for firm soils before trying to mow the crop, to avoid stand damage. In addition, alfalfa could use a little time to recover from waterlogging stress. So some patience is advised.

Once the soils are firm though, how can we get  hay cured as quickly as possible? Here I describe proven techniques that shorten the time between cutting and storing the crop.

Most of this article is reprinted with permission from an article published in Farm and Dairy on June 2, 2010, available at It still applies this year.

Haylage vs. hay:

Consider making silage or haylage instead of dry hay, whether it is stored in silos or bagged silage or as wrapped bales. Since haylage is preserved at higher moisture contents, it is a lot easier to get it to a proper dry matter content for safe preservation than it is to make dry hay. Proper dry matter content for chopping haylage can often be achieved within 24 hours as compared with to 3 to 4 days for dry hay.

Proper dry matter content for silage ranges from 30 to 50% (50 to 70% moisture) depending on the structure used, while wrapped balage should be dried to 40 to 55% dry matter (45 to 60% moisture). Compare that to dry hay that should be baled at 80 to 85% dry matter (15 to 20% moisture), depending on the size of the bale package. The larger and more dense the package, the dryer it has to be to avoid spoilage

Mechanically condition the forage:

Faster drying of cut forage begins with using a well-adjusted mower-conditioner to cause crimping/cracking of the stem (roller conditioners) or abrasion to the stems (impeller conditioners). At least 90% of the stems should be cracked or crimped with roller conditioners or show some mechanical abrasion when using impeller conditioners.

Some excellent guidelines for adjusting these machines can be found in an article by Dr. Ronald Schuler of the University of Wisconsin, available online at (

Consider desiccants:

Desiccants are chemicals applied when mowing the crop that increase the drying rate. The most effective desiccants contain potassium carbonate or sodium carbonate. They are most effective on legumes than grasses and most useful for making hay rather than silage or balage. Desiccants work best under good drying conditions, but don't help much when conditions are humid, damp, and cloudy. Consider the weather conditions before applying them.  

Maximize exposure to sunlight:

Exposure to the sun is the single most important weather factor to speed drying. So the trick is to make the sun shine on as much of the cut forage as possible. This can be done by making the windrows as wide as possible, especially this time of year when our dry weather windows can be short. Wide windrows provide for maximum forage surface area to be exposed to the sunlight.

I once heard someone say "You can’t dry your laundry in a pile, so why can you expect to dry hay that way?"

The swath width should be about 70% of the actual cut area. The mowers on the market vary in how wide a windrow they can make, but even those that make narrow windrows have been modified to spread the windrow wider. Details can be found in articles at the Univ. of Wisconsin website mentioned above.

Another way to spread out and aerate the crop for faster drying is with a tedder. Tedders are especially effective with grass crops, but can cause excessive leaf loss in legumes if done with the leaves are dry. Tedders can be a good option when the ground is damp, because the crop can be mowed into narrow windrows to allow more ground exposure to sunlight for awhile, and then once the soil has dried a bit the crop can be spread out.

When making haylage, if drying conditions are good, rake multiple wide swaths into a windrow just before chopping. For hay, if drying conditions are good, merge or rake multiple wide swaths into a windrow the next morning when the forage is 40 to 60% moisture to avoid excessive leaf loss.

Recent research studies and experience have shown that drying forage in wide swaths can significantly speed up drying. Faster drying in wide swaths results in less chance of rain damage, and it produces higher quality forage. Studies  reported by the University of Wisconsin showed that wide swaths (72% of the cut width) result in lower NDF and higher energy in the stored forage.

Consider a preservative:

Sometimes the rain just comes quicker than we have time for making dry hay. As mentioned above, making haylage helps with this problem, but another option is to use a preservative.

The most common and effective preservatives are based on proprionic acid. This acid can be caustic to equipment, but many buffered proprionic preservatives are available on the market that reduce this problem.

The preservatives inhibit mold growth and so allow safe baling a moisture contents a little higher than the normal range for dry hay. Carefully follow the manufacturer directions and application rates when using preservatives.

Watch wet bales carefully!

If you do happen to bale hay at higher moisture contents than desired, keep a close watch on it for two to three weeks. You should invest in a hay temperature probe and monitor the internal temperature of the hay during the first three weeks.

Every year someone’s barn burns down because of spontaneous combustion of wet hay. So if you have hay that is on the wet side, keep it outside or in a well-ventilated area. Don’t stack wet hay either, because that prevents the heat and moisture left in the hay from escaping.

It is normal for hay to go through a “sweat” in the few days after baling. Internal temperatures of 110 F in the first five days after baling are quite common in our region and are not a concern.

Hay bale temperatures of  120 to 130 F will likely result in mold growth and will make the protein in the hay less available to animals. But at those temperatures, there still is not a danger of fire. The concern is if mold growth causes the temperature to go even higher.

If the temperature in the hay continues to rise, reaching 160 to 170 F, then there is cause for alarm. At those elevated temperatures, other chemical reactions begin to occur that elevate the temperature much higher, resulting in spontaneous combustion of the hay in a relatively short period of time.

My hope is that a disastrous hay fire never happens to you or someone you know! It can be avoided by careful attention to the management practices I’ve outlined here and of course with a little cooperation from the sun! My best wishes to you for quick, safe, and successful hay and haylage making this season! 

Enterprise Unit Subsidy Qualification - A Revised Interpretation

Editor's note: Schiefer Insurance Services helped author this article.

In order to receive the enhanced enterprise unit subsidy, some of your crop must be planted.

FCIC Handbook Section 10 (C) (3) (a,b)

(3) Qualifications. To qualify for EUs:

(a) The EU must contain all of the insurable acreage of the same insured crop in:

1. Two or more sections, if OUs are available by sections;

(b) Each of the above [(a)1-(a)6] that are used to qualify for the EU must have planted acreage that constitutes at least the lesser of 20 acres or 20 percent of the insured crop acreage in the EU. If there is planted acreage in more than two sections,……, these can be aggregated to form at least two parcels to meet this requirement.

RMA just released the official interpretation of this rule.

The minimum planted amount is (the lesser of) 20% or 20 acres of your insured corn acres planted in at least each of two sections. The insured corn acres are the total of your reported planted and unplanted corn acres.

Keep in mind that the second section can be an aggregate of multiple sections.

For Example:

1. Farmer A has the intent to plant 200 acres of corn. To meet the requirements he must plant a minimum of 20 acres in one section and 20 acres in a second section. The second section could be an aggregate of two or more sections equaling the 20 needed.

2. Farmer B has the intent to plant 80 acres of corn. To meet the requirements he must plant a minimum of 16 acres in one section and 16 acres in a second section. The second section could be an aggregate of two or more sections equaling the 16 needed.

If you haven’t planted a minimum amount, you can use the time allowed in the late planting period (June 5 – June 30) to qualify.

The premium savings associated with qualifying for enterprising is significant.

This information is meant to inform and does not replace the terms and conditions set forth in your 2011 MPCI policy.

Nutrient Applicators Association Meeting

If you use manure as fertilizer or are interested in using it, attend the Midwest Professional Nutrient Applicators Association (MPNAA) summer meeting. The meeting’s focus will be on applying manure to growing crops.

Due to the wet spring it has been difficult to find an opportunity to apply manure to fields. Applying to growing crops widens the application window as well as increases crop nutrient uptake by getting the nutrients to the crops when they are most needed. The meeting date is June 29 in Marysville, Ohio and is open to non-MPNAA members as well.

This meeting is being held in conjunction with the ODA’s Certified Livestock Manager (CLM) training. This training is two days. June 28 covers the rules and regulations of managing on farm nutrients while the second day is combined with the MPNAA meeting. Anyone who buys, sells or land applies more the 4,500 dry tons or 25 million gallons of liquid manure per year or anyone who manages and/or handles manure at a major concentrated animal facility is required to become a CLM.

Both dates offer CLM and CCA continuing education credits. For more details and registration information please visit Questions can be directed to Amanda Meddles at or 614-292-6625.


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Crop Observation and Recommendation Network

C.O.R.N. Newsletter is a summary of crop observations, related information, and appropriate recommendations for Ohio crop producers and industry. C.O.R.N. Newsletter is produced by the Ohio State University Extension Agronomy Team, state specialists at The Ohio State University and the Ohio Agricultural Research and Development Center (OARDC). C.O.R.N. Newsletter questions are directed to Extension and OARDC state specialists and associates at Ohio State.