Head scab risk remains low across most of North Carolina. For wheat flowering today, risk is LOW throughout North Carolina EXCEPT it is medium in Dare County and pockets of the counties north of the Albemarle Sound. Wheat heads are susceptible to Fusarium infection from early flowering through about 7 days after mid-flowering. Fungicides containing QoIs (strobilurins) should be avoided after flag leaf stage, as they can increase DON (AKA vomitoxin) in a scab epidemic. Miravis Ace, Prosaro, Caramba and Proline are about equally effective in reducing scab at early wheat flowering and even several days later. None of those products, including Miravis Ace, is as reliably effective in suppressing scab if applied before flowering, e.g., at 50% heading. In other words, better a little late than early with scab-targeted fungicide applications. Monitor scab risk at wheatscab@psu.edu.

-- Christina Cowger, Small Grains Pathologist, USDA-ARS and North Carolina State University

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

Welcome to the 2021 Fusarium Head Blight Prediction Center. The Prediction Center was renovated this past year and you may need to refresh your web browser to enjoy some of the new features. Please take a few minutes to familiarize yourself with the locations of help documents (“?” Button), assessment date selection (calendar), and model selection tools (menu button in the upper left).

The Prediction Center is currently focused on an OK, MO, AR, TN, KY, NC and Southern VA. Wheat in these states likely approaching the heading and flowering stages of growth when the crop is most vulnerable for infection by the Fusarium fungus. Currently, the risk maps indicate the risk is low in most areas of country. With moisture in the form of rain and humidity in the forecast, the risk may change rapidly.

--Erick DeWolf, Extension Plant Pathologist, Kansas State University

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

If you have a small grain crop nearing heading, it’s time to keep an eye on the risk of Fusarium head blight (scab). Scab risk in North Carolina and surrounding states is low for fields flowering now, and the forecast is mostly dry, so risk will remain low for crops heading and flowering in the next 7-10 days. To monitor risk, go to the web site wheatscab.psu.edu. In the upper left corner, the plus key lets you zoom in. Just above it, clicking on the square allows you to choose the level of resistance of your wheat variety. If you don’t know it, assume it is susceptible.

The risk of a severe scab epidemic is given as low (green), medium (yellow), or high (red) for a given area on the map. Risk is always for the assessment date given at the top of the map. The map always “wakes up” with today’s date; you can manually change the date to previous dates if desired. The map is showing you the risk for a wheat crop flowering on that date. Wheat is vulnerable to scab when it is flowering, and barley is vulnerable when heads emerge from the boot. A fungicide targeting scab is only recommended when risk is medium or high at the time your wheat is flowering, or your barley is emerging from the boot.

-- Christina Cowger, Small Grains Pathologist, USDA-ARS and North Carolina State University

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

Due to wet soils and a late spring, many wheat and barley fields are maturing late this year in North Carolina.  The FHB forecasting website shows medium to high risk across the Coastal Plain and Tidewater, but keep in mind the risk prediction is for wheat flowering today (or your chosen assessment date).  Most small grain fields in North Carolina are in the jointing phase.  Monitor your scab risk closely when your wheat is heading and your barley is in the boot.  Wheat is susceptible to scab when it flowers.  Barley is susceptible when heads emerge from the boot.  Those are the growth stages at which to apply a scab-targeted fungicide IF risk is medium or high.

-- Christina Cowger, Small Grains Pathologist, USDA-ARS and North Carolina State University

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

Welcome to the 2021 Fusarium Head Blight Prediction Center. The Prediction Center was renovated this past year and you may need to refresh your web browser to enjoy some of the new features. Please take a few minutes to familiarize yourself with the locations of help documents (“?” Button), assessment date selection (calendar), and model selection tools (menu button in the upper left).

The Prediction Center is currently focused on southern states where wheat is actively growing and likely moving through the jointing and flag leaf emergence stages of growth. The risk maps indicate the risk is currently low in most areas of LA, MS, AL and GA. Wheat in these areas of the country are likely to enter the vulnerable growth stages over the next two weeks.

-- Stephen Crawford

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

Welcome to the 2021 Fusarium Head Blight Prediction Center.  The Prediction Center was renovated this past year and you may need to refresh your web browser to enjoy some of the new features. Please take a few minutes to familiarize yourself with the locations of help documents (“?” Button), assessment date selection (calendar), and model selection tools  (menu button in the upper left).  

 The Prediction Center is currently focused on southern states where wheat is actively growing and likely moving through the jointing and flag leaf emergence stages of growth.  The risk maps indicate the risk is currently low in most areas of LA, MS, AL and GA. Wheat in these areas of the country are likely to enter the vulnerable growth stages over the next two weeks.

-- Stephen Crawford

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

This will likely be the last small grains disease update for the 2020 cropping season. I didn't update the commentary at the beginning of the week as nearly all wheat and barley acres reached anthesis the week before and all fungicide decisions for the season had been made. Instead, I took the past few days to get some idea of how widespread and severe FHB infections are in the region. It is not hard to find FHB in the yield trials in NW Minnesota. The field severities are nowhere near disastrous but high enough in some of the more susceptible varieties that you would be faced with discounts upon delivery of the grain to the elevator because the DON content will exceed the 2 ppm limit. Severities in the few commercial fields I scouted and some of the comments I received from crop consultants to date is that FHB severities are not bad and even a bit lower than last season. The major difference between the trials and the commercial production is variety selection and the application of a fungicide at Feekes 10.5.

Nonetheless, I encourage to evaluate the extent of the FHB infections in the next two weeks. This is an important first step to not just become aware of the extent of the damages but also to start developing a plan of attack to minimize the impact of these FHB infections on the grain quality.

Your first step to maintaining quality and avoid the potential discounts due to low test weight, fusarium damaged kernels and the presence of DON is to segregate the worst affected fields or areas of fields and not co-mingle the grain. Your second step is to increase the fan speed during harvest to reduce the number of fusarium damaged kernels in the grain tank.

Unfortunately, you will also increase your harvest losses as you increase your fan speed as smaller but otherwise sound kernels will also be left in the field. Often these smaller kernels come from the spikelets above the initial point of infection and where the FHB has grown into the rachis, thereby halting the grain fill of the kernels higher on the rachis. I expect kernel weights to be down anyway as the heat and humidity we have had to endure to date will likely result in smaller kernels than most years.

If needed, the next step is to use a grain cleaner to further reduce the number of fusarium damaged kernels. A Kwik-Kleen grain cleaner or equivalent allows you to clean the grain prior to putting the grain in storage.

Meanwhile, the Wheat Stem Sawfly is completing the summer portion of its life cycle as the larvae are reaching the bottom of the infected stems and are now starting to girdle the lower portion of the stem to build the hatch in their home for the winter in the small piece of stem just above the crown but below the soil surface. Stems infected with WSS will start falling over anytime after the crop has reached physiological maturity and is drying down.

The WSS were alive and well in the Crookston and Fisher area earlier this season when we monitored their emergence. However, I also have received reports of WSS from as far south as Glyndon and well east of Crookston. These are just two reports but if confirmed it points to a further spreading of this 'ink stain'. I once again ask for your cooperation and report any fields you suspect WSS infections.

Good luck and stay safe with the harvest!

--Jochum Wiersma, Extension Agronomist, University of Minnesota Crookston

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

Welcome to the Fusarium Head Blight Prediction Center, 2020. The system has undergone revisions for this year and it may help to familiarize yourself with the interface. The new interface provides a map-based estimate of disease risk for the current date. Users can select other dates of interest from the menu in the upper left portion of the interface. The date selected should correspond to times when your wheat is at or nearflowering, because the crop is most susceptible to infection at this growth stage. There is also a menu icon in the upper left corner that allows users to customize the model predictions for winter vs. spring wheat, and account for wheat varieties with different levels of genetic resistance to Fusarium head blight. The megaphone icon in the upper right activates this commentary display window. The selecting the colored buttons along the top of the commentary window displays state-specific commentary.

The focus of the prediction effort is currently on North Dakota, Northern Minnesota, where later planted spring wheat may still be at the heading and flowering stages of growth. The models indicate a moderate or high level of risk for susceptible wheat varieties in portions of North Dakota and western Minnesota. Growers in these areas should consult with local advisors to determine what other local factors that might also influence the risk of disease.

--Erick DeWolf, Extension Plant Pathologist, Kansas State University

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

Small Grains Disease Update 07/13/20

This past week I found the first Fusarium Head blight (FHB) infected spikelets in my trials near Oklee. This trial was seeded on April 24th and the earliest entries are approaching the soft dough stage. The incidence and severity of the FHB were very low, certainly in comparison to the amount of tan spot and Bacterial Leaf Streak (BLS) present in the canopy. Nonetheless, the presence of infected spikelets confirms that the conditions on the ground were indeed as forecasted by the risk model. The Septoria leaf spotting diseases and leaf rust were still mostly and completely absent, respectively.
The immediate weather forecast calls for rain tonight across much of northwest Minnesota and a period of more moderate temperatures and relative humidities. This bodes well for the grainfill but I doubt that the risk for tan spot, leaf rust, and FHB is going to drop substantially. There is still plenty of soil moisture to create the needed leaf wetness periods to create initial infections for the aforementioned diseases.
It remains therefore imperative to stay vigilant the coming week and apply a fungicide onto the remaining spring wheat acres that have yet to reach the beginning of anthesis (Feekes 10.51). The decision on whether to use tebuconazole or Prosaro/Caramba/Miravis Ace remains difficult. Prosaro/Caramba/Miravis Ace each improve suppression of FHB by about 15% to 20% over tebuconazole.

--Jochum Wiersma, Extension Agronomist, University of Minnesota Crookston

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

A moderate to high level of scab risk exists for susceptible varieties across a large portion of the state. Scab risk for moderately susceptible varieties is moderate to high for areas on the eastern quarter of the state and pockets in northwest ND. Conversations with growers, agronomists and consultants suggest there is a wide range of crop stages in the state, so continue to monitor growth stages in the fields and apply a fungicide if warranted.

--Andrew Friskop, Cereal Extension Pathologist, NDSU Department of Plant Pathology

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org