Lebanon Crop Management Video

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23 July 2014

Corn Ear Molds and Leaf Diseases.


Del Voight – Penn State Extension
Two Items to be reviewing as the corn season progresses. Ears are rapidly forming and growers are applying fungicides presently to fields that the hybrid may be susceptible to leaf diseases.. Knowing the characteristics of the molds are helpful in management. Also many fields of corn were planted late and are showing some leaf diseases. This is important also in determine early harvest prior to complete infection of the plants.
Here are some pictures of ear molds and a description of their mycotoxin potential as well as some management ideas.  As in other cases just because there is the mold does not mean that a mycotoxin will result.  There is still a lot that needs to be learned regarding these molds and there relationship to the toxin formation.  Both fusariums can be an issue and have been researched the most intensively mainly in the silage portion for dairy.  As you get out on farms in the coming weeks it might be wise to have this or some other reference in your truck to use as a discussion.  Also keep an eye on the nitrate situation(silage after rains return) and stalk lodging due to stalk rot. Many times with a drought the plant robs leaves, stalk and roots to feed the ear and during this time stalk rots invade since the plant is weakened.  A squeeze test of the lower stalk can reveal the management of the field for early harvest. 
I have viewed mostly corn smut. at differing stages of development.  This is not a fungus that can cause any harm to livestock contrary many folks will consume it as a delicacy.


Gibberella Ear Rot

 
The most common and important ear mold in Ontario is Gibberella zeae which is the sexual reproductive stage of Fusarium graminearium. This fungus not only infects corn but also small grains such as wheat and can survive on soybean roots. Although, the fungus can produce a white colour mold which makes it difficult to tell apart from Fusarium Ear Rot, the two can be distinguished easily when Gibberella produces its characteristic red or pink colour mold.
Scout fields which have a susceptible hybrid planted. If you are not sure how your hybrid rates for Gibberella contact your seed supplier.
Gibberella Ear Rot is economically important not only because of the potential yield and quality losses but because Gibberella zeae and Fusarium graminearum produce two very important mycotoxins that occur in Ontario, deoxynivalenol (vomitoxin or DON) and zearalenone. These mycotoxins are especially important to swine and other livestock producers since they can have a detrimental affect on their animals. Feed containing low levels of vomitoxin (1ppm) can result in poor weight gain and feed refusal in swine. Zealalenone is an estrogen and cause reproductive problems such as infertility and abortion in livestock, especially swine. If you have Gibberella ear rot (5 % or more) and are planning to feed the grain, you should have the grain tested for these toxins.
Figure 2 - Gibberella Ear Rot





Fusarium Ear Rot
Unlike Gibberella, Fusarium infected kernels are often scattered around the cob amongst healthy looking kernels or on kernels that have been damaged for example by corn borer or bird feeding. Fusarium infection produces a white to pink or salmon-coloured mold. A "white streaking" or "star-bursting" can be seen on the infected kernel surface. Although many Fusarium species may be responsible for these symptoms, the primary species we are concerned about in Ontario is Fusarium verticillioides (formerly Fusarium moniliforme). The significance of this fungus is that it produces a toxin called fumonisin.
Figure 3. Fusarium Ear Rot

Diplodia Ear Rot
The characteristic ear symptom of Diplodia maydis infection is a white mold that begins at the base of the ear and will eventually cover and rot the entire ear. Mold growth can also occur on the outer husk which has small black bumps (pycnidia) embedded in the mold. These reproductive structures are where new spores are produced. Unlike Gibberella and Fusarium, Diplodia does not produce any known toxins.
Figure 4. Diplodia Ear Rot

Penicillium Ear Rot
Penicillium rot (Penicillium oxalicum) produces a light blue-green powdery mold which grows between the kernels and cob/husk surface. Infected kernels could become bleached or streaked. Can be a serious problem if corn is stored at high moisture levels (greater 18%). Although other Penicillium species have been shown to produce Ochratoxins, Penicillium oxalicum dos not and this toxin does not occur in Ontario.
Figure 5. Penicillium Ear Rot

Table 1 – Common Ear Rots and Molds That Occur in Pa and The Primary Mycotoxins They Produce
Corn Ear Rot
Description
Primary
Mycotoxins
Gibberella
(Gibberella zeae also called Fusarium graminearum (asexual stage)
  • Red/pink mold
  • Begins on ear tip
  • Bird, insect injury increases damage
  • Deoxynivalenol (Vomitoxin or DON)
  • Zearalenone
  • T-2 toxin
Fusarium
(Fusarium verticillioides)
  • White, pink or salmon coloured
  • Can occur anywhere on ear
  • Often begins at the sites of insect damage
  • Fumonisins
Diplodia
(Stenocarpella maydis)
  • White mold
  • Begins at base of ear but often entire ear covered
  • Black pycnidia (bumps) on husks and kernels
  • · None
Penicillium
(Penicillium oxalicum)
  • Blue-green mold
  • Mold between kernels and on cobs/husk
  • Ochratoxins (other Penicillium species)
  • P. oxalicum does not produce ochratoxin; not detected in Ontario
Management – Iowa State University.
The best option for moldy grain is to feed it or sell it instead of storing it. However, it should be tested for toxins before feeding. Testing for mycotoxins can be done before putting the grain in storage. The best sampling method is to take a composite sample of at least 10 pounds from a moving grain stream, or to take multiple probes in a grain cart or truck for a composite 10-pound sample. If toxins are present, it is possible that the grain can be fed to a less sensitive livestock species, such as beef cattle, depending on the specific toxin and its concentration. A veterinarian or extension specialist can help with these decisions. If the grain is sold, there may be a reduced price due to mold damage.
Cleaning the grain removes fine particles that are usually the moldiest and most susceptible to further mold development. Good storage conditions (for example, proper temperature and moisture content, aeration, insect control, and clean bins) and regular inspection are essential in preventing mold and toxin development in any stored corn. For additional information on sampling and other aspects of ear rots and mycotoxins, see Iowa State University Extension publications PM 1800, LEAF DISEASESAflatoxins in Corn (free), and PM 1698, Corn Ear Rots, Storage Molds, Mycotoxins, and Animal Health ($1.50 plus shipping).

2014 Barley Performance Data Posted


Posted: July 22, 2014
Many barley varieties recover from winter injury and perform very well in trials
Our 2014 Winter Barley Performance Trial was conducted at the Russell Larson Research Farm at Rock Springs, PA and the results have been posted  . The trial consisted of 15 experimental and commercial hulled lines, 3 hulless lines and 3 malting barley lines. The test experienced some winter injury, which impacted the performance of some lines, but some recovered remarkably well. Yields ranged from 117.9 to 51.9 bu/acre on a 48 lb basis. Test weights were very good with the hulled lines averaging over 51 lb/bu and the hulless lines averaging over 60 lb/bu.
Yield performance was surprising following the winter conditions, which included 8 days with low temperatures below 0 F at this location. The test was planted early in mid September and had some fall fertilizer applied, and both contributed to good fall growth and winter survival. Winter injury was most severe in the malting barley lines and one of the hulless lines, Eve.
In the hulled entries, most of the lines had awns except for Valor, Nomini and Growmark FS 501. Of these lines without awns Valor had the highest yield at 94.2 bu/acre and was the tallest at 40 inches. Among the awned entries, a Virginia Tech experimental line topped the test at 117.9 bu/acre followed by Growmark FS 950 at 106.9 bu/acre.
In the hulless test, the variety Dan had the highest yield at 85.7 bu/acre and exhibited excellent winter hardiness. The new hulless line, VA07H-31WS had a yield of 75.7 bu/a and slightly lower rating for winter hardiness.
We also included three prospective malting barley lines due to the interest in growing malting barley. Endeavor and Charles are two row winter types and Maja is a six row winter types. Each of these had noticeably more winter injury than most of the feed barleys in the test. Endeavor and Charles appeared to recover surprisingly well.
For more information on winter barley performance review results at Virginia Tech and theUniversity of Delaware .

Contact Information

Greg Roth
  • Professor of Agronomy
Email: 
Phone: 814-863-7043

15 July 2014

More resources for Palmer Amaranth- Great time to identify with seed heads fully emerged.


Weed Alert:


Palmer Amaranth has been identified in the North Annville (pictured above) area and growers should be alert to how to manage this weed before it has a chance to become established on their farms.    Palmer amaranth is quite distinctive at this stage with long (10 to 20 inches) cylindrical seed heads generally rising above the soybean crop.  If Palmer amaranth seed are harvested along with the grain, the seeds can quickly spread into neighboring fields or farms.  We are still investigating this most recent occurrence, but strongly suspect that seeds were spread via contaminated manure and/or hay.  Attached are documents from Ohio State University and the University of Illinois providing more details on identification and management of Palmer amaranth.  In addition this 11 minute youtube video is an OSU production helping to explain the concern about Palmer amaranth along with some management options.  We will provide more information about this problem as it becomes available.  In this particular case it is growing in a pasture setting and there are numerous products to eliminate it in that environment. However if you see the seed heads as above it is best to pull and burn those seeds presently to eliminate the seeds populating the weed seed bank.



03 July 2014

Hail and Wind Damage Assessment Resources at Penn State

Del Voight - Penn State Extension
When it comes to the middle part of the season there is always a risk of wind and hail damage to crops. Many times there only a handful of growers that experience significant crop losses, however, to this growers there is nothing more disheartening then to find a crop dessimated by mother nature.  We had a straight line wind event and golf ball sized hail a day ago at about 3 in the afternoon. By 430 I was receiving calls to determine the best course of action.  In most cases I would prefer to wait a week and then go and check due to the fact that over the years I have learned that in most cases there is an exaggerated assessment immediately and a week of growth can really make the difference in determining options.  But with local government agencies needing some initial assessment I decided to go out the day after and check.  I assessed several fields in the most affected area and most if not all the corn that was hailed on though dramatic will grow through it with minimal impact.  I use  the hail damage fact sheet more to illustrate to producers the impact and try to sort through how the crop will react.  Penn State Hail Damage Assessment and options.  Young corn prior to V9 will take allot of leaf removal before a yield impact.  In my experience with 20% damage growers assume it is a complete loss when in fact at that level little to perhaps a 4% damage might result. Again refer to the Hail Damage Assessment worksheet to balance research with applied use in the field.
There are other factors with light now shining to the soil more weeds might germinate. The damage to the tissue might allow infection of leaf diseases and the crop might be delayed in maturity.  So there is the need to inspect fields and make decisions to assist growers in determine additional management to alleviate these concerns whether it be an application of a fungicide and or another run over the field to apply additional weed control products.
Disease risks associated with hail damage(Source Illionois Extension via Corn and Soybean Digest)
It is important to remember that a fungicide application cannot recover yield potential lost due to hail damage. Fungicides protect yield potential by reducing disease. There are some diseases of corn that are favored by wounding, e.g., Goss’s wilt, common smut and stalk rot. Similarly bacterial blight and bacterial pustule on soybeans are favored by wounding. Fungicides are not effective against the pathogens that cause these diseases. The foliar diseases that are managed by fungicides (e.g., gray leaf spot, northern corn leaf blight, eye spot and common rust on corn, and brown spot and frog eye on soybeans) are caused by pathogens that do not require wounds for infection. These foliar diseases will influence the yield response to fungicides more so than hail damage.
On Left should be fine fine larger corn on right had 10% snapped corn and 30% defoliation will be left to go to harvest
In a few cases where the plant is broken below the grower point from a one two shot of hail and wind resulting in green snap then we get into a replant condition which then requires questions on what herbicides were applied which affect the options for replant and also if corn itself can be replanted. It also brings to the forefront what to do with the existing crop I have seen corn killed with a fatty acid inhibitor such as Poast and replanted within a day turn out to be a satisfactory option when small. Large corn with 14 leaves however creates a whole other matter of dealing with a forage that will need to be mowed, wilted and combined with a starch to help with fermentation. Two years ago a grower bush hogged tasseled corn and had to wait for the fodder to dry before no tilling could commence to adequately cut the fodder. There are many facets to this issue that not alot of research exists.
Wind blown corn with green snap on majority 40%  of plants and some 50%  that are leaning.  Considering replant
The wind areas that I observed and walked into present another challenge.
This field is leaning over roots are intact and there is little green snap. Should rise back up will check in  a week.
 Some fields are simply leaning over and the roots are firmly attached while in other cases the roots are pulled up.  Green snapped stalks indicate the show is over same with the corn with the roots torn out. The leaning corn in most cases will right itself if done prior to tasseling and be acceptable for harvest.  At this point growers need to asses what percent of the stalks are snapped? % with roots torn from soil? What is the planted population?  All of these factors need to wieghed to make a decision. Today I observed a field with 9 foot corn about V13 with 30% snapped off with a population of 42,000ppa of corn that would leave about 28,000ppa leaning so in the end we would best leave the crop for a week and most likely it will be acceptable to go to harvest. A field less than a mile away about the same stage of growth had 30,000 ppa and had 50% green snap with 50% leaning with about half the field affected so in that case it might be prudent to consider harvesting  and replanting.
The take home here is that typically the damage is not as dramatic as it may seem.  By checking some key factors such as percent damage, root and stem fitness and most important stage of growth a better management decision can be arrived at that is acceptable given these types of events.

02 July 2014

Now is the time to gather Soybean Leaves for plant tissue testing.


Del Voight- Penn State Extension

Several growers are considering more high yield management for the soybean crop. There are alot of foliar fertilizer products with ideal nutrient levels for numerous micronutrients. Our research indicates tremendous variation in the response to these products.  Yield enhancement is tied to whether the plant is deficient in micronutrients or not.  Since we cannot test the soil with accurate assessments of micronutrients, the best way to determine hidden hunger is with a simple $24.00 plant tissue test. A few growers last season enjoyed 90 bu/acre plus while managing for high yield soybean crops.  The first step is to gain an accurate soil test an maintain optimum levels of P 150ppm and K 300ppm . The second step is to collect a sample at the R1 to R2 stage(full flower) for plant analysis. The Ag Analytical Lab provides the testing for the results.  Here are the specifics to gather the samples.
Once the plant begins to flower R1 which is expected to occur on early May planted fields in the next two weeks gather the samples and send them off via overnight mail to gain quick results. This will allow for adequate time to determine a nutrient strategy before peak growth at R3 when pods are being filled.  .

Soybean Specifics  
Soybeans or other beans
Seedling stage (less than 12")
or
All the above ground portion.20-30 plants
Prior to or during initial floweringTwo or three fully developed leaves at the top of the plant.20-30 upper leaves

Interpretive Nutrient Levels for Plant Analysis

Soybeans plant tissue levels


LowNormalHighExcessive
Nitrogen (% DW)3.104.015.517.01
Phosphorus (% DW)0.160.260.510.81
Potassium (% DW)1.261.712.512.76
Calcium (% DW)0.210.362.013.01
Magnesium (% DW)0.110.261.011.51
Sulfur (% DW)0.160.210.412.00
Manganese (ppm DW)1521101251
Iron (ppm DW)3151351501
Copper (ppm DW)5103151
Boron (ppm DW)10215681
Zinc (ppm DW)10215176

01 July 2014

Sprayer Width Impact on Soybean Yield

Del Voight - Senior Extension Educator - Penn State Extension CMEG
. Growers will need to ascertain running soybeans over to apply many of the vast foliar products such as fungicides, insecticides, fertilizer and biostimulants. With the knowledge that soybean leaf diseases are forecasted to be at threshold levels this summer, considerations for running the beans over will be on growers minds. Two projects that detailed the impact of trafficking in standing soybeans have been researched and I have the two links included below. If we were to only look at an application with a Fungicide applied at R3 the costs would appear close to the following:
Cost of materials- $15.00/acre
Custom application - $12.00/acre
Reduced yield due to trafficking - ???? depends on width of sprayer.
Total costs could be close to $30.00/acre. That would mean at least a 3 bu/acre increase or protection should compensate for the direct costs. What about the sprayer impact?
In Pa data over time we have shown between 2-4 bu/acre increase due to a fungicide application so the economics are close to breakeven. This is where the boom width is important if a grower owns a 45 foot boom and the losses based on science suggest a loss of about 4% 2.5 bu/acre @(60 bu/acre yield)versus a loss of .75%(.5 bu/acre) with a 120 foot boom, then the economics can lean toward a profit for utilizing a wider boom if available. The higher commodity prices do demand revisisting thresholds and determine the best integrated approach.  Growers need to make  thier own decisions but the following two factsheets provide some informed research that might help with the decision.





http://www.extension.purdue.edu/extmedia/SPS/SPS-103-W.pdf

pH and Water modifications to improve pesticide performance.

Del Voight- Penn State Extension
I read with interest an article from an Pesticide Education Specialist  Reeves Petrof from Montana State University regarding Pesticides and water.   Pesticides and Water .   Here is a brief over view of key points Reeves Petrof details in his factsheet.  I have also added items for the Penn State Vegetable guide as well as the Penn State Water Resources Team.  Pesticides are chemicals and when introduced into water may react depending on the hardness of the water. Cations(+)  and anions(-)are similar ot magnets.  Hard water typically has a positive charge so if a pesticide is an anion or negative charge they will bind together and will not seperate once applied to the pest in question. This reduces the effectiveness of the product.  A simple water test of your primary spray water supply now will determine how you manage the water this season. Most farms water sample for either dairy, swine and poultry so a water test should be relatively simple to locate and or gain. Here is a simple table to the hardness of water.  
Hardness is the make up  of the minerals in the water and may contain either Ca++, Mg+++or Fe+++
Soft is below 50ppm
Medium Hard is 50-100ppm
Hard is from 100-200ppm
Pesticide Affects?
I have had several herbicide and insecticide failures that I could not diagnose for certain but I had suspected issues with the water. All of the cases that  I was involved in happened to be in spray tanks that were filled but not were idle overnight before being emptied and I had theorized a reaction with the water rendered the pesticide useless. One take home message is to avoid allowing cerrtain pesticides to remain in the tank for any long term timeframe.  One example  I was involved with  included Dimethoate which can react in literally minutes after mixing pending the water pH.   Salt-formulated  herbicides such as Roundup (glyphosate), Poast  (sethoxydim), Pursuit ( imazethapyr), and Liberty (glufosinate) are subject to being bound in the water and for this reason many labels instruct to lower the pH of the water to ensure optimum performance.  These minerals may bind with salts of certain  herbicides and with some surfactants to form an insoluble salt. These insoluble salts then “fall out” out of solution decreasing herbicide or surfactant  efficiency. In the case of isopropylamine salt  formulations of glyphosate, the positively charged cations of calcium (Ca2+) and magnesium (Mg2+) salts compete with the isopropylamine in the formulation for association with the glyphosate anion (negatively charged). This results in the herbicide having a greater difficulty absorbing into the plant leaf. 
 In addition, research has shown that extremely hard  water, 600 ppm (35 grains/US gallon), can almost  completely antagonize 2,4-D amine applied at a low  rate of about 4 to 8 ounces per acre. Hard Water also affects fungicides and insecticides so it is important to read the labels of all products to determine ideal pH ranges. Here is a small list of some common products in addition to the glyphosate formulations which is more widely recognized.
      Common  Name Trade Name Half-life* at Different pH Values**
Fungicide Example
      Propiconazole       Tilt           Most effective in pH 5 to 9; use within 12 to 16 hours.
      captan              Orthocide        pH5 = 32 hours,      pH7 = 8 hours,      pH8 = 10 minutes
Insecticide Examples
      carbaryl            Sevin               pH7 = 24 days,       pH8 = 2.5 days,     pH9 = 1 day
     dimethoate        Cygon,            pH4 = 20 hours,      pH6 = 12 hours,     pH9 = 48 minutes
     Permethrin       Pounce             Optimum stability pH 4
Herbicide Examples
     paraquat    Gramoxone Extra not stable in pH above 7
Plant Growth Regulators
     Gibberellic Acid   Promalin       A buffered wetting , final spray should not  exceed pH 8

READ THE LABEL!
So how do you reduce the hardness of the water?

Note: Acidifiers should not be used in conjunction with some organo-silicone adjuvants as increased 
acidity may enhance chemical breakdown of the adjuvant. In addition, sulfonyl urea herbicides (Accent, Harmony etc) can degrade in acidic environments below 7. READ THE LABEL!
 The most widely used materials to help with hard water is AMS.
1.  Ammonium Sulfate (NH4SO4). Ammonium sulfate (AMS) has been used successfully to increase herbicide efficacy on a broad spectrum of weed species. This is particularly true for the weak-acid herbicides like Roundup (glyphosate), 2-4--D, Pursuit (imazethapyr),, Poast (sethoxydim) and Basagran (bentazon).. The AMS adjusts the pH so that more of the active herbicide is transported across the leaf surface and into the plant.. An added benefit is that tsulfate ions (SO4) bind up with hard water minerals. In addition, ammonium-herbicide combinations are more easily absorbed by some weed species. A general rule-of-thumb for adding AMS is the addition of 2% AMS by weight or 17 lb of dry AMS per 100 gallons of water for most applications. AMS should be added to the spray carrier solution prior to the herbicide and always, consult the pesticide label for mixing instructions. There may be limitations on the use of fertilizer-based surfactants. The industry has strived to make this process simpler for the applicator by liquifying AMS and there are numerous products that are liquid AMS(Turbo and numerous others) and each product needs to be added at the appropriate rate according to the label to effectively bind the hard water. They can range from a per acre to a per 100 gallon dilution. There are some new products in this arena that either are AMS and or UAN derrivitives. .  Halo is relatively new the area and has been used to replace AMS, Turbo, Request, Choice, and other similar products. 
2.  Organic Acids.  A very effective treatment is utilizing citric acid..  The addition of an organic acid such as food grade citric acid will effectively remove hard water ions from solution. Organic acids are effective because the conjugate base (negative portion) of the acid binds to and removes positively charged cations from solution. A weak acid, such as citric acid, will provide a stronger conjugate base, and therefore, will be more effective than a strong acid such as nitric or hydrochloric acid. The addition of the organic acid will also lower the spray solution pH because of the addition of hydrogen (H+) ions. Organic acid is added to the water carrier prior to the addition of the herbicide. A use rate of 2.2 lbs of citric acid per 100 gallons of water should be adequate for water with 250 ppm of Ca2+. From my travels many poultry growers have citric acid on hand for use in the poultry watering system.
3.  Some sources of Urea Ammonium Nitrate(UAN) may also reduce the hardness but not as effective as AMS and this is why AMS is preferred over UAN.  Some UAN utilizes a Sulfuric Acid source to add Sulfur to the fertilizer mixture and may enhance the acidification from UAN.  

Use the following general guidelines once you have determined the pH is of your spray water. Remember, READ THE PESTICIDE LABEL. 
 • pH 3.5-6.0 Satisfactory for most spraying 
and short-term (12 to 24 hours) storage of 
most pesticide mixtures in the spray tank. 
Read the label. Not suitable for sulfonylurea (Accent, Harmony)
herbicides 
• pH 6.1-7.0 Adequate for immediate spraying 
of most pesticides. Do not leave the spray 
mixture in the tank for over 1 to 2 hours to 
prevent loss of effectiveness. 
• pH 7.0 and higher. Add buffer or acidifier. 
You can offset the effects of water pH by adding certain adjuvants (additives) that can either change the pH or your spray mixture or maintain (buffer) the levels of dissolved solids and organic particulate matter….dirt! These soil particles decrease Roundup (glyphosate) and paraquat activity and can cause equipment wear. This type of antagonism cannot be corrected by adding AMS or an organic acid. Always choose a water source that is free of dirt, grit, and organic matter. 
Adjuvants and Surfactants. 
Water softening additives designed for pesticide applications are available to offset hard water problems. While nonionic surfactants will generally enhance herbicide activity on most weed species, they will not 
overcome the antagonism between salt-based herbicides and hard water. Therefore, under hard 
water conditions, AMS or organic acids should be used in conjunction with nonionic surfactants to 
maximize herbicide absorption. Read the label of surfactants that you buy. Some AMS surfactants 
already have a nonionic surfactant added pH if it already at the desirable level. Here is an older however useful  Factsheet that UAP has produced with Loveland regarding its LI700 product that is a penetrant as well as a hard water solution .LI 700 UAP this product is designed to aid in penetration as well as reduce pH. I am not promoting their product rather the fact that they have a large list of pesticides and their pH requirements. There are numerous other products similar to this product so check with your supplier for these products and use.
Final Thoughts

  1. The key is to read the label
  2. Gain a water test
  3. Fill the tank half to 2/3rd full and add the water treatment BEFORE adding any of the products that are affected by the pH or Hardness.
  4. Add other products in the right order to ensure mixing.
By following some simple rules the maximum effectiveness of herbicides, insecticides, fungicides and plant growth regulators may be achieved and avoid failures in the field.