White Masses on Stems of Redbud

Joe Boggs, Extension Educator. Originally posted on the Buckeye Yard and Garden Online

Small, sticky, snowy-white masses are appearing on the stems of redbuds (Cercis canadensis) in southern Ohio.  They could easily be mistaken for soft scales, mealybugs, or insect egg masses.  However, they are the “egg plugs” of a treehopper originally named the Two-Marked Treehopper (Enchenopa binotata, family Membracidae).

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Assessing The Risk of Frost Injury to Late Planted Corn

Source:  Peter Thomison, OSU

Lately I have received questions as to whether corn at various stages of development, especially the blister (R2) and dough (R4) stages, will mature before the 50% average frost date. According to the National Agricultural Statistics Service, as of August 18, 37 percent of Ohio’s corn acreage was in the dough stage (R4) compared to 70 percent for the five year average, and three percent of the corn acreage was in the dent stage (R5) compared to 21 percent for the five-year average. Many areas of the state corn are considerably behind the five-year average because of late planting. Late maturation of the corn crop had led to questions about the likelihood for frost damage and whether more fuel will be needed to dry corn.

Physiological maturity (R6), when kernels have obtained maximum dry weight and black layer has formed, typically occurs about 65 days after silking. At physiological maturity (kernel moisture approximately 30-35%), frosts have little or no effect on the yield potential of the corn crop.

Dr. Bob Nielsen has summarized research findings from Purdue University and Ohio State University that provide insight into both the calendar days and thermal time (growing degree days, GDDs)  typically required for grain at various stages of development to achieve physiological maturity (kernel black layer, R6). This research was conducted at two locations in Indiana (west central and southeast) and two locations in Ohio (northwest and southwest) with three hybrids representing 97, 105, and 111-day relative maturities planted in early May, late May, and mid-June. The calendar days and thermal time from silking to black layer for the 111-day hybrid maturity are shown in Table 1 from http://www.agry.purdue.edu/ext/corn/news/timeless/RStagePrediction.html. The calendar days and thermal time from silking to black layer for the 97-day hybrid and 105 maturity are also available from this Purdue webpage.

Table 1

The study indicated that corn planted in mid-June compared to early May requires 200 to 300 fewer GDDs to achieve physiological maturity.  According to Dr. Nielsen, while slightly different responses among the four locations of the trial existed, there did not seem to be a consistent north/south relationship. Therefore, growers can use the results summarized in the following table to “guesstimate” the number of calendar days or heat units necessary for a late-planted field at a given grain fill stage to mature safely prior to that killing fall freeze.

How many GDDs can be expected from now until an average date of a killing

frost for a 111-day hybrid planted in mid-June?  To answer this question, estimate the expected GDD accumulation from Aug. 19 until the average frost date (50% probability) for different regions of the state (Table 2).  These GDD expectations are based on 30-year historical normals reported by the Ohio Agricultural Statistics Service. The GDD accumulation was calculated using the 86/50 cutoff, base 50 method.

If you want to determine the “youngest stage of corn development” that can safely reach black layer before the average frost date at a given weather station, use the information in Table 2 on remaining GDDs in conjunction with Table 1 which indicates GDDs needed to reach black layer at various stages of grain fill. Compare “GDDs remaining” for the site with the GDDs required to achieve black layer depending on the corn’s developmental stage.

Table 2. Estimated GDDs remaining from Aug. 9 to the first fall frost for Ohio.

 

 

Region

Median Frost Date

(50% probability)

Estimated GDDs Remaining

From Aug. 19 to Fall Frost

Northwest Oct 10 – Oct 20 673 – 723
North Central Oct 10 – Oct 25 656 – 741
Northeast Sept 30 – Oct 25 603 – 749
West Central Oct 10 – Oct 15 716 – 773
Central Oct 5 – Oct 15 670 – 796
East Central Sept 30 – Oct 15 645 – 763
Southwest Oct 10 – Oct 15 752 – 815
South Central Oct 15 – Oct 20 841 – 893
Southeast Oct 5 – Oct 15 651 – 774

If your corn is in the milk stage (R3) as of Aug. 19, will it be safe from frost? Table 1 indicates that corn planted in mid – June required about 681 GDDs to reach black layer from R3 and Table 2 indicates that all regions of the state can accumulate that number of GDDs before the 50% frost date.

However, if your corn is in the blister stage (R2) as of Aug. 19, it might be a different story. The kernel development – GDD accumulation relationships in Table 1 indicate that corn planted in mid-June that is at R2 needs about 781 GDDs to reach black layer. Table 2 indicates that three regions of the state, South Central, Central, and Southwest, accumulate that number of GDDs before the 50% frost date. Several other regions, West Central, and Southeast, come close to accumulating this number whereas, the Northeast, Northwest, and North Central regions are least likely to accumulate the GDDs required to achieve physiological maturity.

The research results in Table 1 demonstrate that late-planted corn has the ability to adjust its maturity requirements, and most of this adjustment occurs during the late kernel development stages. In previous growing seasons when GDD accumulation was markedly less than normal, corn planted by mid-June has usually achieved physiological maturity before the first frost occurred.

Corn Growth & Development – R3 Milk

Today managing your corn crop requires knowledge of the different growth stages of the corn plant.  Growth stage identification is critical for scouting and proper timing of fertilizer and pesticide applications.  Throughout the growing season I will discuss the various corn growth stages and management issue at each stage. 

R3 – Milk

The R3 (Milk) stage occurs about 18 – 22 days after silking.  At this stage the outside of the kernel is colored yellow while the inside is white.  The kernel contains a “milky” white fluid that will explode when pressure is applied.  Kernel moisture content is approximately 80% and starch is beginning to accumulate in the kernel.

Management/Scouting: Scout for drought symptoms.  Stress can still cause kernel abortions from the ear tip downward.  Insects: Corn Earworm, Corn Rootworm adults and Japanese Beetles Diseases: Eyespot, Gray Leaf Spot, Norther Leaf Blight, Southern Leaf Blight and Tar Spot

Photo Source: Corn Growth & Development, Iowa State University

OHIO AG LAW BLOG—Case watch: LEBOR and Lake Erie battles linger

Source: OHIO AG LAW

It’s been a while since we’ve written about the Lake Erie Bill of Rights (LEBOR)! As a refresher, LEBOR was passed in February in a special election as an amendment to Toledo’s city charter.  LEBOR was meant to create new legal rights for Lake Erie, the Lake Erie ecosystem, and to give Toledo citizens the ability to sue to enforce those legal rights against a government or a corporation violating them.  For a longer explanation on LEBOR, see our post here.  Since then, lawsuits for and against LEBOR have been filed, and the state of Ohio has passed legislation concerning the language in LEBOR. Updates on those actions will be discussed below.

Update on the Drewes Farm lawsuit

The day after LEBOR passed, Drewes Farm Partnership initiated a lawsuit in the U.S. District Court for the Northern District of Ohio, Western Division, against the city of Toledo. Our initial blog posts concerning this lawsuit are available here and here.  In May, we discussed updates to the Drewes Farm lawsuit in yet another blog post.  Since our last update, the Lake Erie Ecosystem and TSW’s motion to stay pending appeal and the appeal were both denied, meaning the Sixth Circuit agreed with the district court’s decision to leave the ecosystem and TSW out of the lawsuit.  As a result, the current parties to the lawsuit are plaintiffs Drewes Farm Partnership and the State of Ohio, as well as the defendant City of Toledo.  In early June, both the Drewes Farm Partnership and the state of Ohio filed motions for judgement on the pleadings.  The district court has not yet determined whether to grant the motions; the City of Toledo’s response to the motions is due on August 9, 2019.  After the response is filed, the plaintiffs will have a chance to reply.

Toledo Citizens file lawsuit against State of Ohio Continue reading

Hot Night Temperatures Can Decrease Corn Yield

Source: Peter Thomison, Alexander Lindsey, OSU

Night time temperatures can affect corn yield potential. High night temperatures (in the 70s or 80s degrees F) can result in wasteful respiration and a lower net amount of dry matter accumulation in plants. Past studies reveal that above-average night temperatures during grainfill can reduce corn yield by reducing kernel number and kernel weight. The rate of respiration of plants increases rapidly as the temperature increases, approximately doubling for each 13 degree F increase. With high night temperatures more of the sugars produced by photosynthesis during the day are lost; less is available to fill developing kernels, thereby lowering potential grain yield. High night time temperatures result in faster heat unit or growing degree day (GDD) accumulation that can lead to earlier corn maturation, whereas cool night temperatures result in slower GDD accumulation that can lengthen grain filling and promote greater dry matter accumulation and grain yields.

The Pioneer Insight article referenced below concludes….

“Although higher night temperatures undoubtedly increase the rate of respiration in corn, research generally suggests that accelerated phenological development is likely the primary mechanism affecting corn yield.”

Research at the University of Illinois conducted back in the 1960’s indicated that corn grown at night temperatures in the mid-60s (degrees F) out yielded corn grown at temperatures in the mid-80s (degrees F). Average corn yields are generally much higher with irrigation in western states, which have low humidity and limited rainfall. While these areas are characterized by hot sunny days, night temperatures are often cooler than in the Eastern Corn Belt.  Low night temperatures during grain fill (which typically occurs in July and August) have been associated with some of our highest corn yields in Ohio. The cool night temperatures may have reduced respiration losses during grain fill and lengthened the rain fill period. Cooler than average night temperatures can also mitigate water stress and slow the development of foliar diseases and insect problems.

Corn Growth & Development – R2 Blister

Today managing your corn crop requires knowledge of the different growth stages of the corn plant.  Growth stage identification is critical for scouting and proper timing of fertilizer and pesticide applications.  Throughout the growing season I will discuss the various corn growth stages and management issue at each stage. 

R2 – Blister

The R2 (blister) stage occurs about 10 – 12 days after silking.  At this stage the kernel is visible and resembles a blister.  The kernel is filled with clear fluid, the embryo is barely visible and it is at about 85% moisture.

Kernels are in a rapid period of grain-fill.  Rapid and steady grain-fill will continue through R6.  If severe stress occurs now or during R3, kernel abortion will occur from the tip of the ear downward.  Kernel abortion will continue until the plant has has enough carbohydrates for the remaining kernels.

Silks outside the husk leaves are drying and changing in color from tan to light brown.  The silks will naturally detach from their kernels following fertilization.

 

 

Perspectives on 2019 Corn and Soybean Acres: Impact of Prevent Plant

Source: farmdoc daily(9):151, Department of Agricultural and Consumer Economics, University of Illinois at Urbana-Champaign, August 15, 2019.

The Farm Service Agency (FSA) of the U.S. Department of Agriculture released county acreages for crops and prevent plantings based on acreage reports filed by farmers.  Even though prevent plant totaled 19 million acres in the United States, planted corn acres in 2019 are only slightly lower than 2018 values.  With notable exceptions, corn acres decreased in counties that had large areas of prevent planting and increased in acres with little prevent planting.  Soybean acres fell over the vast majority of counties in the United States.

FSA Acreage Data

FSA released their first set of 2019 county-level acreage data on August 1 (see Crop Acreage Data of FSA).  This data indicated that there were 85.9 million acres of corn planted in the United States, down by 1% from the 2018 plantings of 86.4 million acres (see Table 1)

The 2019 planting number (85.9 million acres) is expected to increase as FSA continues to update values monthly until January 2020.  From 2011 to 2018, corn acreage in the final January report averaged 1.8% higher than the initial August report.  However, in recent years, the increase has been much lower.  From 2016 to 2018, the January value was .7% higher than the initial August value.  A 1.3% increase – the average from 2011 to 2018 – would increase 2019 planted corn acres to 87.4 million acres.  A .7% increase – the average from 2016 to 2018 – would increase planted acres to 86.4 million acres, roughly the same as the planted acreage for 2018. Continue reading

Poultry Litter Applications

Source: Glen Arnold, OSU Extension

Stockpiles of poultry litter can be seen in farm fields across Ohio. While common each year in wheat stubble fields, there are also stockpiles showing up in preventative plant fields.

Poultry litter is an excellent source of plant nutrients and readily available in most parts of the state.  Poultry litter can be from laying hens, pullets, broilers, finished turkeys, turkey hens, or poults. Most of the poultry litter in the state comes from laying hens and turkey finishers. Typical nutrient ranges in poultry litter can be from 45 to 57 pounds of nitrogen, 45 to 70 pounds of P2O5, and 45 to 55 pounds of K2O per ton. The typical application rate is two tons per acre which fits nicely with the P2O5 needs of a two-year corn/soybean rotation.

Like all manures, the moisture content of the poultry litter greatly influences the amount of nutrients per ton. Handlers of poultry litter have manure analysis sheets indicating the nutrient content.

Poultry manure for permitted operations needs to follow the Natural Resource Conservation Service 590 standards when being stockpiled prior to spreading. These include:

– 500 feet from neighbors

– 300 feet from streams, grassed waterways, wells, ponds, or tile inlets

– not on occasionally or frequently flooded soils

– stored for not more than eight months

– not located on slopes greater than six percent

– located on soils that are deep to bedrock (greater than 40 inches to bedrock)

Farmers who want to apply the poultry litter delivered to their fields are required by Ohio law to have a fertilizer license, Certified Livestock Manager certificate, or be a Certified Crop Advisor. Check with your local Soil and Water Conservation District for proper setbacks from steams, ditches and wells when applying poultry litter.

Estimating Yield Losses in Stressed Corn Fields

Source: Dr. Peter Thomison, OSU Extension

Drought stressed corn near tassel emergence

Many corn fields are still silking (and some are just past the mid-vegetative stages)….so, it may seem a little early to discuss estimating grain yields. However, according to the most recent  NASS crop report, for the week ending Aug. 8, 2019,  25% of the corn crop has reached the dough stage (compared to 63% for the 5 year average). Corn growers with drought damaged fields and late plantings may want to estimate grain yields prior to harvest in order to help with marketing and harvest plans. Two procedures that are widely used for estimating corn grain yields prior to harvest are the YIELD COMPONENT METHOD (also referred to as the “slide rule” or corn yield calculator) and the EAR WEIGHT METHOD. Each method will often produce yield estimates that are within 20 bu/ac of actual yield. Such estimates can be helpful for general planning purposes.

THE YIELD COMPONENT METHOD was developed by the Agricultural Engineering Department at the University of Illinois. The principle advantage to this method is that it can be used as early as the milk stage of kernel development, a stage many Ohio corn fields have probably achieved. The yield component method involves use of a numerical constant for kernel weight which is figured into an equation in order to calculate grain yield. This numerical constant is sometimes referred to as a “fudge‑factor” since it is based on a predetermined average kernel weight. Since weight per kernel will vary depending on hybrid and environment, the yield component method should be used only to estimate relative grain yields, i.e. “ballpark” grain yields. When below normal rainfall occurs during grain fill (resulting in low kernel weights), the yield component method will OVERESTIMATE yields. In a year with good grain fill conditions (resulting in high kernel weights), the method will underestimate grain yields.

In the past, the YIELD COMPONENT METHOD equation used a “fudge factor” of 90 (as the average value for kernel weight, expressed as 90,000 kernels per 56 lb bushel), but kernel size has increased as hybrids have improved over the years. Dr. Bob Nielsen at Purdue University suggests that a “fudge factor” of 80 to 85 (85,000 kernels per 56 lb bushel) is a more realistic value to use in the yield estimation equation today. https://www.agry.purdue.edu/ext/corn/news/timeless/YldEstMethod.html

According to Dr. Emerson Nafziger at the University of Illinois under current drought stress “…. If there’s a fair amount of green leaf area and kernels have already reached dough stage, using 90 [as the “fudge-factor “] might be reasonable. It typically doesn’t help much to try to estimate depth of kernels at dough stage, when kernel depth is typically rather shallow anyway, especially if there are 16 or more kernel rows on the ear. If green leaf area is mostly gone, however, and kernels look like they may be starting to shrink a little, kernels may end up very light, and using 120 or even 140 [as the “fudge-factor”] might be more accurate”. http://bulletin.ipm.illinois.edu/article.php?id=1695.

Calculate estimated grain yield as follows:

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Forage Focus: Getting to Know Your Weeds

In this edition of Forage Focus, host Christine Gelley, an Extension Educator with The Ohio State University Agriculture & Natural Resources in Noble County is joined by Clifton Martin, OSU Extension- ANR Educator for Muskingum County, for a segment on “Getting to Know Your Weeds.” Clifton and Christine will identify weeds commonly found in Ohio pastures and hay fields, and address the principles of managing them.