Lowndes – Echols Ag News

Distillers Grain Offers Supplementation Options For Beef Cattle Producers

Dr. Lawton Stewart gives recommendations on feeding distillers grain. Across most of Georgia, most producers have experiencing ample rain and plenty of forage, therefore, winter supplementation is far from their thoughts.  However, now is a great time to start planning ahead.  Typically, three large factors taken into consideration when selecting a supplement are convenience, cost, and nutrients supplied.  Often times, we combine the latter two and look at cost per unit of nutrient (e.g. $/lb of protein or energy).  Unfortunately, sometimes nutrients supplied are sacrificed to maximize convenience or low cost.

Over past two decades, ethanol production has increased, and in turn, the byproduct of this industry (distillers grains) has become more available.  The growing popularity of this feedstuff has led to extensive research evaluating distillers grains in beef cattle production.  In fact, several studies have been conducted at the University of Georgia in an effort to evaluate its value, as well as ways to utilize it in a convenient manner.  For the remainder of this article, the discussion will focus on dried distillers grains with solubles (DDGS) because this is the most common form utilized in Georgia.

 

Nutrient value and mineral considerations

A summary of the nutrient analysis of approximately 130 DDGS samples submitted to Cumberland Valley Analytical Services (Waynesboro, PA) from the Southeast is presented in Table 1.  This byproduct can be fed as a protein source to replace other more expensive sources such as soybean meal.  Distillers grains are also an excellent source of energy, often testing between 85 and 95% total digestible nutrients (TDN).  The form of energy also makes distillers grains attractive for grazing cattle.  Since the starch is removed, the energy derived from distillers grains is primarily digestible fiber and some fat.

The mineral content of distillers grains should also be taken into consideration.  Dried distillers grain is high in phosphorus (P) and sulfur (S), but low in calcium (Ca). Supplemental Ca should be provided to balance the high phosphorus levels to maintain a Ca:P ratio above 1.5:1. If this ratio stays low for extended periods of time, urinary calculi, or “water bellies” may occur.  Also, excessive P excretion can have negative impact on water sources increasing the risk of algal bloom.

Sulfur tends to be high and can vary widely between ethanol plants and can be as high as 1%.  The total ration should remain below 0.4% S to avoid issues such as Polioencephalomalacia, or more commonly referred to Polio or “brainers”.

Typically, DDGS should be limited to 30-40% of the total intake to avoid any negative impacts of excessive minerals while utilizing the protein and energy available.

Potential for heat damage

Distillers grains is high in moisture directly after the distilling process and is typically dried down to make transportation and storage easier. If excess heat is applied during the drying process, the protein in DDGS can be heat-damaged and become bound protein.  This reduces its utilization by cattle.  This damage can easily be detected by visual inspection.  Properly dried DDGS will have a light golden color; however, as it becomes heat damaged, it will darken in color and have a distinctive burnt odor.  Figure 1 illustrates the visual difference in an undamaged and a heat damaged load of DDGS.  Analysis of load-A, golden in color, indicates 30.7% CP and 2.3% bound protein, while load-B, darker in color, is 26.9% CP and 9.9% bound protein.  The adjusted CP, or available protein, for load –A and –B is 28.4% and 17%, respectively.  This can create protein deficiencies if not taken into consideration when balancing a ration.

Utilizing DDG in a free-choice hot-mix

An on-farm trial was conducted in Northeast Georgia to develop a hot mix to allow producers to feed DDGS free choice but maintain intake to a safe level.  In this trial, weaned heifers were offered tall fescue hay (56% TDN and 10% CP) with DDGS.  At first, DDGS was offered free choice, however daily intake reached 12 lb/hd, twice the recommended level!  A premix containing salt, limestone, and trace mineral (Table 2) was formulated to limit intake of DDGS while balancing the mineral content.  This “hot mix” limited the intake of DDGS to approximately 40% of the daily dry matter intake for both developing heifers (7.8 lbs) and bred heifers (9.3 lb), and resulted in average daily gains of 1.95

lb for weaned heifers and 1.07 lb for bred heifers.  A hot mix is a supplement that contains an intake limiter and allows a producer to put out enough feed to last several days with intake remaining relatively constant across that time.  This results in a feed strategy that is more convenient than feeding on a daily basis.  This DDGS hot mix could easily be utilized for brood cows and bulls.  In fact, several producers have reported success stories from utilizing this strategy.

 

Despite limitations with sulfur, phosphorus, and fat, distillers grains offer producers an additional option for protein and energy supplementation when cost is not prohibitive.  Additional research has been conducted in Georgia evaluating distillers grains for developing bulls, stocker cattle, and finishing cattle.  For information on the results of these studies, or assistance developing beef cattle rations utilizing distillers grains, please contact your local Extension office (1-800-ASK-UGA-1; extension.uga.edu).  Additional information can be found in UGA Extension Bulletin 1482,Using Distillers Grains in Beef Cattle Diets.

Corn kernel Rot/ Ear Molds

  1. Harvest early (or at least “on-time”) – The longer corn sits in the field in our hot, humid environment with the ever-present chance of rain in the forecast, the worse these molds will get. Encourage growers to harvest as soon as corn is ready to minimize this risk.
  2. Set fans high – smaller kernels near the tip of the ear tend to have the greatest infection. Our best opportunity to “clean” the grain is to blow small and infected kernels out the back of the combine during harvest.
  3. Dry and cool grain quickly – A major condition of early harvest (at high moisture) is that growers will need to immediately dry grain down and practice sound grain storage (if they are storing it). Storing grain too wet and too warm will favor fungal growth and greater infection.                                                                 Author Reagan Noland

August Cotton Newsletter

Cotton Management Considerations for the Remainder of 2018 (Mark Freeman)

 

The 2018 Georgia cotton crop is extremely variable in maturity. Much of the state has had cotton blooming and setting fruit for weeks where as other parts of the state still has a large portion of the crop yet to bloom. There is no one size fits all approach to management of this crop and decisions should be made accordingly.

 

With much of our crop planted late due to the rainfall in late May and June, we must remember that the window for blooms to become harvestable bolls is compressed compared to a full season crop. It is important during that early bloom period to minimize stress to the crop in order to retain as much lower node fruit as possible as the cotton does not have time to compensate for losses early on. Remember that the best way to manage vegetative growth is by having high early season fruit retention. This limits the amount of available carbohydrates that the plant can use towards vegetative growth later in the season. PGRs should also be used to limit vegetative growth and enhance lower node retention.

 

When should we terminate our PGR applications? Research conducted at UGA and other parts of the country suggest that PGR applications should cease when cotton reaches 5 nodes above white flower. In theory a late season mepiquat application could stop further vegetative growth and divert carbohydrates and resources to boll production, but research has shown that there is no benefit to cotton yields, plant heights, fiber quality, or regrowth potential after defoliation.

 

One more note on PGRs, with the widespread rain across the state, the issue of rainfastness has been a concern when applying mepiquat. The rain free period after mepiquat chloride application is 8 hours. Although tank mixtures with an adjuvant are not necessary, their use may aid in plant uptake and help shorten that rain free window. Another option is Pentia (mepiquat pentaborate). Pentia requires a rain free period of two hours after application and that can be reduced to one hour when Pentia is tank mixed with an adjuvant.

 

If irrigation water is available, all steps should be taken to ensure that the crop does not encounter drought stress when adequate rainfall has not occurred. This is especially true for the first six weeks following first bloom as this is the period of peak water demand. Irrigation scheduling has been a topic of conversation and research for the past few years and several quality cotton irrigation scheduling methods exist which use soil moisture sensor technology. However, if a grower does not intend to utilize one of these methods they are encouraged to follow the UGA Checkbook irrigation schedule which can be found on page 132 of the 2018 UGA Cotton Production Guide. One thing to note when using this method is that rainfall or irrigation amounts do not “carry over” to the next week. For example, if water demand for a particular week was 2’’/week and you receive 3”, that extra inch does not affect the amount of water required for the following week.

 

 

Insects (Phillip Roberts)

 

Silverleaf whitefly (SLWF) adults have been observed in low numbers in cotton in some areas during the past week to ten days.  To date very few immature whiteflies have been observed in cotton.  We are not aware of any field which has exceeded threshold for SLWF.  Most reports include observations of individuals or a few adults when searching plants for corn earworm.  However, the presence of SLWF in a field is worth noting and management of all insect pests must consider the presence of SLWF.  All efforts should be made to minimize the need to treat SLWF with insecticide.

Management Considerations:

  1. Scout for the presence of SLWF adults.  It is important to know if SLWF is present!
  2. Conserve beneficial insects, do not apply insecticides for any pests unless thresholds are exceeded (beneficial insects will also suppress corn earworm).
  3. If SLWF is present in a field, avoid use of insecticides for other pests which are prone to flare SLWF.
  4. Scout fields frequently for adults and immatures once fields are infested with SLWF.
  5. Be timely with SLWF insecticides when thresholds are exceeded (many learned in 2017 that it is difficult to play catchup with SLWF).
  6. Be very aware of SLWF infestations in hairy leaf varieties and late planted cotton, these are high risk fields.

There is no question that agents, scouts, consultants, and growers are looking more closely for SLWF this year based on the problems we had in 2017.  Historically if we see SLWF in cotton during the month of July we should anticipate problems with SLWF, especially on late planted fields, and manage appropriately.  Infestations do not come close to where we were a year ago.  In 2017 treatable populations first occurred during the last week of June and many acres were treated in July; so we are in a much better situation this year compared to last.  It will be important that all fields are monitored closely for SLWF and hopefully proper proactive management can minimize damage and the need for SLWF insecticides.  Your County Agent has additional information on management and scouting of SLWF in cotton.

Scout All Cotton For Corn Earworm

Bt cotton technologies have allowed cotton growers to significantly reduce insecticide inputs for caterpillar pests.  However Bt cotton is not and has never been immune to corn earworm (CEW).  Since commercialization of Bt cotton, a percentage of Bt cotton grown in Georgia has required supplemental treatment of CEW with foliar insecticide in most years.  Introduction of 2-gene Bt cottons significantly reduced the need for CEW sprays compared with the original single gene Bt cotton.  The industry is beginning to transition to 3-gene Bt cottons which will improve efficacy against CEW compared with 2-gene Bt cottons.

In recent years susceptibility of CEW to Bt cotton has significantly declined in parts of the US (especially in the Midsouth and North Carolina).  Only a small percentage of 2-gene Bt cotton has required supplemental treatment for CEW in Georgia during recent years so we have not observed this decline in efficacy in the field (or have we?); this is due in part to low corn earworm infestations in cotton.  However we did see a slight increase in CEW insecticide applications during 2017.

UGA researchers have seen reduced field efficacy in Bt corn in Georgia.  We have also seen reduced efficacy of the original Bt toxin in bioassays for CEW collected in Georgia.  Basically what is happening is CEW is/has developed resistance to the Cry1Ac gene.  If the original Bt gene is no longer providing control of CEW, our 2-gene Bt cottons (Bollgard 2, WideStrike, and TwinLink) will be relying on a single gene and overall efficacy will be reduced.  There is variability in performance of Bt cotton technologies.  The chart to the right illustrates relative efficacy of commercially available Bt technologies.  Note that all Bt technologies continue to provide excellent control of tobacco budworm!

 

Bottom line is that all Bt cotton must be scouted on a regular basis and growers must be prepared to act accordingly if thresholds are exceeded.  When scouting pay close attention to blooms, bolls with stuck bloom tags, and small bolls.  When corn earworm escapes occur in Bt cotton they are usually observed near or just below the uppermost white bloom.  The threshold for CEW in Bt cotton is when 8 larvae ¼ inch or greater are found per 100 plants.  We recommend scouts search the top 12 inches of plants and one bloom, one bloom tagged boll, and one small boll per plant.  Remember that larvae must hatch and feed on the plant to ingest the Bt.  However if larvae reach ¼ inch in length survival is likely.  React in a timely manner with supplemental foliar sprays if thresholds are exceeded.  Coverage and penetration of the canopy with insecticides will be important as escaped CEW will be down in the canopy. Only spray other pests (i.e. stink bugs) based on thorough scouting and appropriate thresholds.  Conservation of beneficial insects such as bigeyed bugs will reduce the risk of CEW issues.

 

Diseases (Bob Kemerait)

 

August is a Critical Month for This Year’s Target Spot Control and Next Year’s Nematode, Fusarium Wilt and Bacterial Blight Control

One of the most important components of disease and nematode control in the cotton crop is “timeliness”.  “Timeliness” means deploying the best management tactic to fight diseases and nematodes before these foes become well-established or before the opportunity to use a tactic has passed.  August is a very important time in the cotton season to both be timely for possible fungicide applications this season and for preparation for next season.

Foliar Diseases.  As of the fist of August, there are four foliar diseases active in some, but certainly not all, cotton fields in Georgia.  These include bacterial blight, caused by Xanthomonas citri pv. malvacearum, Stemphylium leaf spot, caused by the fungus Stemphylium solani, target spot, caused by the fungus Corynespora cassiicola, and areolate mildew, caused by the fungus Ramularia spp.

There is little that can be done to manage bacterial blight at this time in the season, other than to note if it has occurred in your fields and which varieties have been affected.  Because of weather during the summer of 2018, even varieties which have shown some level of resistance to bacterial blight in the past have been affected this year.  However, now is the time that growers should note the level of bacterial blight in their crop and begin to make decisions as to variety selection for 2019.  Growers have an increasing number of “bacterial blight resistant” varieties from which to choose.

 

Photo Greg Slaughter

Stemphylium leaf spot is characterized by numerous small spots with dark purple/brown margins and often times gray, papery centers.  This disease occurs when the cotton plant is deficient in potassium; potassium deficiencies may exist because of poor soil fertility, perhaps from leaching, or during periods of drought where potassium is not taken up into the plant.  Stempylium leaf spot is managed by insuring proper levels of potassium in the plant; fungicides are not an effective management tool.

Photo Jason Brock

 

Target spot became evident in southwestern Georgia in the latter part of July and is likely present in many fields across the Coastal Plain of the state.  Target spot can develop quickly and is most common in good-growing cotton with high yield potential.  Extended periods of leaf wetness, where the foliage in the interior of the canopy remains wet well into the later morning hours, create perfect conditions for rapid development of target spot and premature defoliation from it.  Fungicides are an important management tool for target spot, though use does not always result in increased yields.  From our research, effective use of fungicides should be considered between the first and sixth week of bloom where the third week of bloom is typically the most critical time of management.  Scouting before use of fungicides to determine if the disease is present help to ensure that an application is warranted.  Priaxor is currently the most effective fungicide for control of target spot, though Headline, Quadris and others are also effective.

Areolate mildew was especially severe in 2017 and there are reports that the disease is back in 2018 if a few fields.  Areolate mildew has historically been confined to southeastern Georgia east of I-75; however it can be found elsewhere as well.  Typically arriving too late in the season to cause any damage (in fact, late-season defoliation may be a benefit), use of fungicides had often not been warranted.  However, in severe cases, the same fungicides used to control target spot are also effective in the management of areolate mildew.  Growers within three weeks of defoliating their cotton need not worry about managing areolate mildew.  Where areolate mildew occurs in a crop with anticipated defoliation a month or more away, and weather is favorable for continued development and spread of the disease, then use of a fungicide may be beneficial to protect yield.  Unfortunately, we have very little data at this point with which to refine our recommendations for management of areolate mildew.

 

It is too late to protect our 2018 cotton crop from plant-parasitic nematodes of Fusarium wilt; however now is the time that symptoms become very evident in the field.  Where stunting, poor growth and even dying plants are found in areas of a field, growers should take measures to determine 1) is it caused by nematodes?, 2) if so, what kind of nematodes, and 3) is Fusarium wilt also involved.  Detection and identification now will help growers to make best variety selection and possible use of nematicides in 2019.

 

Important Dates:

 

Field Days:

 

Midville – Southeast Research and Education Center – August 15th

Tifton – Cotton and Peanut Field Day – September 5th

 

For more information on any of the discussed topics please contact your local UGA Extension Agent.

Reductions in Grass Control in 2018? (Prostko)

Getting plenty of calls about perceived reductions in grass control after applications of ACC-ase inhibiting herbicides, such as Select (clethodim) or Poast (sethoxydim), have been applied.  Some folks first reaction to this “lack” of control is that we suddenly have widespread ACC-ase resistance.  When its comes to the issue of resistance, I will never say never.  But, before traveling down that bumpy road, I would like for you and your growers to consider the following:

1) Currently, only 2 grass species have been “officially” confirmed to have evolved ACC-ase resistance in Georgia including large crabgrass and Italian ryegrass. Scientific confirmation of herbicide resistance takes lots of time, manpower, and greenhouse space.

2) Labeled heights for optimum control of various common grasses with Select, including crabgrass, Texas panicum crowfootgrass, and goosegrass, are 2″- 6″.  

3) The following is some data illustrating the effect of Select rate and timing on the control of goosegrass.  Please note that goosegrass control was reduced by 16-23%, depending upon rate, when applied at the 4-6 tiller stage of growth.

Figure 1.  Goosegrass control with Select applied at different rates and timings.

4) If Cadre (imazapic) was applied prior to the grass herbicide application, it is very likely that grass control will be reduced.   Research has shown that Cadre can reduce the photosynthetic rate of goosegrass which then reduces the sensitivity of the ACC-ase enzyme to clethodim (Burke and Wilcut.  2003.  Physiological basis for antagonism of clethodim by imazapic on goosegrass.  Pesticide Biochemistry & Physiology) 

5) At this time of the year, peanut plants are kinda tall (> 12″).  Thus, any grass plants peaking out of the top of the peanut canopy are not likely to be adequately controlled due to size and coverage issues.

6) Before dropping the R-bomb, please double-check use rates, stages of growth, adjuvants, rain-free periods, and field history.  The threat of herbicide resistance is definitely real but it does not happen in one night.

Row Crop Disease Update August 10, 2018

Dr. Bob Kemerait gives row crop disease update:

DISEASES of PEANUT:  White mold and leaf spot aren’t breaking lose in every peanut field in Georgia, BUT hot temperatures, high humidity and frequent rains have created near-perfect conditions for the development, spread and, sometimes, explosion of these diseases.  Growers need to stay on a good fungicide program, tightening spray intervals where disease is becoming problematic and/or where there is concern if the crops have received enough drying time after a fungicide was applied.

FOUR COTTON DISEASES:  Target spot, areolate mildew, Stemphylium leaf spot, and bacterial blight.

What a season it has become when target spot and areolate mildew are causing greater angst than bacterial blight.

 

EASY STUFF:

 

  1.  Bacterial blight is present and is affecting yield in some fields.  Susceptible varieties will get this disease and losses may occur.  THERE IS NOTHING TO BE DONE ABOUT IT NOW. However, growers should note the varieties where they find it and determine at the end of the season if the disease became severe enough to avoid planting those varieties again.
  2. Stemphylium leaf spot is present as well.  Stemphylium leaf spot is caused by a deficiency in potassium in the plant.  Dr. Glen Harris is our soil fertility expert; I believe he would agree that excessive rains could have leached potassium this year.  Fungicides ARE NOT a solution for Stemphylium leaf spot; Dr. Harris has the best information about managing potassium.

 

HARD STUFF:

 

  1.  Target spot and areolate mildew are present in a number of fields this year.
  2. At times, target spot and areaolate mildew appear late enough in the season that the defoliation resulting from these diseases does not affect yield and use of fungicides is not needed.
  3. The question for both diseases is not, “Can we protect the cotton in this field with a fungicides?” but rather, “Should we protect the cotton in this field with a fungicide?”
  4. We have very very little data on areolate mildew, but from what I do have, I am confident that we can easily control this disease using strobilurin products like Headline or Quadris, or mixed products like Priaxor or Elatus.  Proline may work as well but I don’t have data.
  5. Though we can control areaolate mildew, does it make us any more yield than if we didn’t control it?  When conditions are favorable, areolate mildew can rapidly defoliate a cotton crop.  If a grower is withing 3-to-4 weeks of defoliating anyway, I would NOT use a fungicide.  If the crop still had 4 or more weeks to go, I would consider weather, yield potential, how much disease is in the field and then decide to spray or not.
  6. If areolate mildew, or target spot, is already well-established in the field (i.e. causing significant defoliation, then there is little hope that a fungicide will help.
  7. Target spot is a significant concern this year and is widespread.  Not every cotton grower in the state needed to spray a fungicide for target spot, but I encourage growers to carefully consider their options.
  8. Target spot is of particular concern this year because a) the wet and warm conditions are perfect for an explosion of the disease, b) the disease has been found early in many fields, and c) the price of cotton makes protection 100-250 lbs lint/acre attractive.
  9. I believe the best window of opportunity for managing target spot is from the first week of bloom to the sixth week of bloom.
  10. A little target spot in a crop (meaning scattered spots on lower leaves and no defoliation) during the first week of bloom and favorable weather IS a concern, as it would be at the third week as well.  A “little target spot” at the 4th-6th week of bloom is much less of a concern.
  11. When a fungicide program begins as early as the first week of bloom because of the disease situation; a second application may be beneficial two-to three weeks later.  I don’t envision an application, follow-up or otherwise, after the 6th week.
  12. It will be quite difficult to control (impossible?) target spot if there is already significant defoliation in the field before an application is made.  If 25-30% of the leaves are already gone, a fungicide likely won’t work.
  13. THE  THREE MOST IMPORTANT POINTS TO MANAGE TARGET SPOT, in order of importance, are 1.  TIMING  2.  COVERAGE  3.  SELECTION of FUNGICIDE.

Bermudagrass Stem Maggot Control Options

Chemical Control

Many of us county agents are working with Dr. Lisa Baxter who is helping look for new products with BSM efficacy. Still today the use of a pyrethroid labeled for forage use around 10 days after the previous cutting appears to be the best strategy for control. Sometimes a second application 10 days later will be beneficial, especially if the forage is growing slowly. UGA Extension Forage Scientist Dr. Dennis Hancock adds that some formulations add residual control for fall armyworm, but residual insecticides (chlorantraniliprole, dimilin, spinosad, etc.) have proven ineffective at preventing the BSM. They are great for FAW, though. So, consider formulations or tank mixes with them when we start seeing more FAM show up.

Physical Control

With some who missed the first cutting and damage is showing up (6 to 8 inches tall), the best option is to cut or graze the field now and encourage regrowth. It’s better to cut early and accept the loss than have low-yielding, damage crop harboring fly populations. This also prevents shading of any regrowth. The maggot does not remain in cut stems. It exits the stem to the soil and adult flies escape to field margins and other fields. A prompt treatment gives best reduction in damage.

Varieties with smaller stems and leaves seem to be more susceptible to damage. Below is a table from the updated publication Managing Bermudagrass Stem Maggot.

Update on Stored Grain Protectants

News Release (7/16/2018)

For Immediate Dissemination

Contact: Dr. Michael Toews, UGA Extension Specialist on Grain Storage (mtoews@uga.edu)

Update on Stored Grain Protectants:

Empty Bin Treatments

Centynal EC. This is a good product for treating empty bins and elevator boots.  Note that the active ingredient in Centynal EC, Defense SC and Suspend SC are identical.

Defense SC (labeled for empty bin use only).  This is a good product for treating empty bins and elevator boots, but is not labeled for application directly to grain.  Note that the active ingredient in Centynal EC, Defense SC and Suspend SC are identical.

Suspend SC. This is a good product for treating empty bins and elevator boots.  Note that the active ingredient in Centynal EC, Defense SC and Suspend SC are identical.

Tempo SC (labeled for empty bin use only). Tempo is a good product for treating empty bins and elevator boots, but is not labeled for application directly to grain.

 

Direct Application to Shelled Corn and Grain Sorghum

 

Actellic 5E. This product has long been the standard for use on corn and grain sorghum. A full rate will provide protection from weevils for 9-12 months.  Reducing the rate will decrease the longevity of the protection.  UGA data suggest that Actellic is susceptible to heat degradation in the drier when grain temperatures exceed 120 F.

Centynal EC.  Centynal EC is a new formulation that will provide 3 to 6 months of protection from weevils.  This material is heat stable in the drier (tested up to 150 F).

Diacon IGR.  Diacon IGR is an insect growth regulator that is effective for killing nearly all immature grain moths and beetles, except weevils.  The 4 oz per 1000 bu rate is sufficient for tank mixing.

Diacon IGR PLUS. This product is a premix of Centynal EC and Diacon IGR.

Malathion. Although widely used in the past, this product is no longer recommended due to well documented resistance in many stored grain insect populations. Expect malathion to break down in the drier.

Sensat. This product is new to the market, but has been in our evaluation program for several years.  Test results show excellent weevil control for up to 12 months.  No dryer stability data at this time.

Storcide II. Storcide II is labeled for use on wheat and grain sorghum, but not corn.  Protection will degrade with heat and time.

Suspend SC.  This product is an older formulation that must be completely suspended before measuring and requires frequent agitation.  It provides 3 to 6 months of protection from weevils.

Three-way tankmix (only tested on corn).  UGA tests from 2014-2018 showed that a three- way tank mix of Centynal (8.5 oz) plus Diacon IGR (4 oz) plus PBO-8 Synergist (13.5 oz) per

1000 bu will provide 6-9 months of protection from weevils.  This is a moderately priced option for growers in markets where other products are unavailable or cost is a limiting factor.

Regardless of the product used, be mindful that grain protectants are not a silver bullet.  Shelled corn should be dried to a maximum of 15.5% moisture content before dropping into the storage bin and must be immediately aerated to further reduce moisture content. Chemical applications should only be made to clean grain that will be stored for more than 3 months.  Apply protectants at the bottom of the auger in a course spray to maximize coverage as the kernels are moving up

to the top of the bin.  Long-term grain storage requires moisture content below 14%, proper housekeeping, use of a spreader when filling bins, and managed aeration.

 

Additional information is available in the 2018 Georgia Pest Management Handbook or in a recent Extension Publication (http://www.aces.edu/pubs/docs/I/IPM-0330/IPM-0330.pdf) that was published with colleagues at Auburn University.

Kissing bugs in Georgia

Kissing bugs in Georgia not cause for

Chagas’ disease worry

By Nancy Hinkle, UGA Professor of Entomologist, Jule-Lynne Macie,

UGA ANR Program Development Coordinator, & Heather N. Kolich, UGA Cooperative Extension Agent

November 25, 2015

 

Between media coverage of Texas kissing bugs transmitting

Chagas’ disease to people and a recent news article reporting that a “deadly” kissing bug was found in Georgia, people are worried. Fortunately, here in the Southeast, these insects are not a public health concern.

Kissing bugs are not a public health concern in Georgia.

 

Kissing bugs are in the insect family Reduviidae, which includes several different species, such as beneficial assassin bugs and large, menacing looking wheel bugs (Arilus cristatus). While these insects can deliver a painful bite if handled, they’re not the Genus of insect that carries the Trypanosoma cruzi parasite that causes Chagas’ disease.

Wheel bugs (above) are often mistaken for kissing bugs.

Although kissing bugs have been present in the Southeast for many decades, the Centers for Disease Control and Prevention, located in Atlanta, has never recorded a case of Chagas’ disease caused by the parasite

some of the insects may carry. Blood-feeders, kissing bugs in Georgia tend to live in the nests and burrows of their animal hosts, typically raccoons, opossums, skunks and armadillos. Furthermore, the parasite doesn’t pass from insect to mammal through a bite. Instead, if the trypanosome

parasite is present, it is shed through the feces of infected

 

insects. Humans can become infected by ingesting or inhaling the feces, or by getting it into their eyes or into a cut or break in the skin.

Kissing bugs will bite humans, especially if they are handled; however, in Georgia, we have certain advantages over areas of Central and South America where Chagas’ disease is endemic. First, our homes tend to be well-sealed, which limits opportunities for the nocturnal insects to visit us as we sleep. Second, the kissing bugs present in Georgia behave differently than those in other regions of the world. In Central and South America, kissing bugs tend to defecate immediately after feeding, leaving potentially parasite-infected feces next to the feeding wound, where it may be scratched into the

broken skin. In Georgia, kissing bugs usually move away from the host before defecating. Since the

parasite is transmitted through the insect’s feces, not through the bite, the victim is much less likely to be exposed to it.

Homeowners with concerns about kissing bugs can take measures to keep insects from entering the house. Repair damaged window screens, replace weather-stripping around doors and windows, and install door sweeps to seal small openings. These measures will also keep out cold air, making the home warmer and more energy efficient this winter.

 

 

Peanut Tank-Mix

Peanut Tank-Mix Thoughts (Prostko)

Rain delays and/or late planting have resulted in continual inquiries about peanut herbicide + fungicide tank-mixes and their potential effects on weed control and crop injury. UGA will never be able to adequately address all concerns with 90,000+ potential tank-mixtures in peanuts. Here is a quick review of some of the published data:

1) When 2,4-DB is tank-mixed with a postemergence graminicide, grass control can be reduced by 8% to 15% approximately 45% of the time.

2) When averaged across 5 grass species, Cadre (imazapic) + Select (clethodim) tank-mixtures provided 19% less effective grass control than Select alone.

3)  Abound (azoxystrobin), Absolute (tebuconazole + trifloxystrobin), Bravo (chlorothalonil) and Headline (pyraclostrobin) are 4 fungicides that have caused significant grass antagonism when tank-mixed with Select (~12% to 30% reductions in grass control).

4) Grass efficacy with Poast (sethoxydim) and Select has not been consistently reduced by tebuconazole (various trade names including Folicur, Orius, TriSum, Integral, Ebustar, Muscle, Tebuzol).  However, when reductions have been significant, grass control was reduced by 4% to 13% with tebuconazole mixes.

5) Palmer amaranth (PA) control was not reduced when 2,4-DB was tank-mixed with Bravo, Provost (prothioconazole + tebuconazole), Headline, or Absolute.  But, 2,4-DB is not that great on PA anyway though?

6)  Sicklepod control with 2,4-DB was reduced by 14% when applied with Abound but not with Bravo or tebuconazole

Is your stocking rate correct?

By Steve Morgan

Harris County CEC

There are many important components in a successful livestock production system. One of the most important tasks in grazing management is understanding livestock stocking rate. It is critical in making timely management decisions that affect profits in beef cattle production. The optimum number of animals on a pasture makes efficient use of the forage and still leaves enough forage behind to allow a quick and complete recovery. Therefore, producers must understand how to determine the correct stocking rate for their pastures.

Stocking rate is defined as the concentration of grazing livestock on a given amount of land over a season, year or period of time. Generally, stocking rate is expressed as “animal units” for a given amount of land. This is to allow stocking rates to universally cover all livestock types since an animal unit is equivalent to 1000 pounds of body weight regardless of the type of livestock. Though stocking rate depends on the intensity of grazing management, most pastures would be approximately 2 acres per animal unit. This would provide a forage allowance of approximately 2.5% of body weight per day. However, not all livestock have the same forage demand as a 1000 pound lactating cow. For this reason, animal unit equivalents (AUE) have been developed to assist with the approximate determination of forage demand based on the kind, class and size of animal.

   Animal                                            AUE  

Cow – dry                                             1.00 – 1.50

Cow with calf                                  1.20 – 1.60

Bull – mature                                   1.25 – 1.75

Calf – weaned                                   0.50 – 0.70

Steer/Heifer – 18 months                  0.80 – 1.00

Sheep – mature ewe or ram             0.20 – .030

Sheep – yearling                              0.15 – 0.20

Goat                                                 0.17 – 0.20

Horse – mature                                  1.25 – 2.00

The usefulness of animal units is especially apparent considering the weight difference among various producers’ livestock and the fluctuation of average weights in a herd over time. For example, the average cow size varies considerably and has increased over the past 50 years. Today’s beef cow averages around 1300 – 1400 pounds. These cows are not equivalent to one animal unit. In addition, forage demand varies within a livestock species based on its growth rate (e.g. heifers and steers vs. mature cow). For example:

If the estimated stocking rate for a 1,000 pound cow is 2 acres, the estimated stocking rate for the 1,150 pound cow (assuming both cows have the same forage intake rate of 2.5 percent of body weight) is found as follows:

1,150 pounds x 2.5% = 29 pounds forage intake per day ÷ 25 pounds forage per animal unit = 1.16 animal units per cow

Therefore, 1.16 animal units per cow x 2 acres per animal unit =

2.3 acres per 1,150-pound cow

Condition of the pasture impacts stocking rate. Factors such as previous grazing management, forage species, age of stand, soil type, texture, fertility level and moisture conditions all impact forage yield and consequently stocking rate.

Livestock need forage year-round, but providing an adequate supply of forage for grazing 12 months out of the year can be challenging. Ideally, forage production should correspond with livestock needs. However, pasture production is variable during the growing season while livestock nutritional requirements are relatively stable or steadily increasing. One way to balance this equation is to make hay from some pastures during periods of rapid forage growth. In addition, calving before rapid growth will allow the period of highest animal need to match the greatest production of quality forage. A second way is to manage for a more uniform pasture growth. Some Best Management Practices to accomplish uniform growth include:

  • Keeping forage healthy and unstressed. These plants begin growth earlier in the spring, produce higher yields through the grazing season and continue growing longer in the fall.
  • Switching from continuous to rotational grazing can extend the grazing season and boost yields, since rotational grazing, by virtue of its rest periods, is less stressful to the forage.
  • Maintaining a good fertility program will extend the season and boost yields.

Many forage problems can be avoided by fertilizing properly. To determine fertilizer requirements, take regular soil tests and follow the recommendations given. Be sure to state the type of pasture being grown when submitting your sample because fertilizer recommendations will be based on the crop stated. Many producers incorporate grass/legume mixtures to meet more of the fertility needs of the pasture. Seeding legumes into poor quality pastures is the most common form of renovation. Legumes reduce dependence on nitrogen fertilizer, complement grasses by balancing forage production throughout the season, and improve pasture quality.

Switching from continuous to rotational grazing increases forage utilization. Forage utilization is a critical component that helps determine stocking rate. Most pastures contain a great deal of forage that is never consumed and eventually decays. Traditional continuous grazing systems may use only 30 to 40% of the available forage. The rest of the forage is either trampled, soiled, or of little nutritional value because it becomes overly mature. Most of this loss occurs with underutilized fall stockpiles and during periods of rapid growth where there is surplus beyond what is needed for livestock. When the appropriate stocking density is used, shortening grazing periods through rotational grazing increases forage utilization to 60-75%.

Good producers strive to achieve the right balance between forage availability, forage utilization, and animal performance. They stock pastures heavily enough to graze available forage down to a target height that will allow rapid and maximum regrowth without compromising nutritional needs of livestock. Good producers will observe pastures frequently for overgrazing and undergrazing and will periodically adjust the stocking rate or movement of cattle as needed. Overstocking and overgrazing leads to a reduction in palatable plant species and an increase in less desirable plants. Overuse also means that livestock must graze for longer periods to meet their needs. Over time, heavy stocking causes the more palatable and productive forage species to disappear. These desirable forages are replaced by less productive, less palatable plants.