Scab risk is low across NC and surrounding states for wheat that is currently flowering. Given the weather forecast, scab risk is likely to remain low for North Carolina wheat flowering over the next several days. It is not recommended to spray for scab when risk is low. To monitor risk, go to www.wheatscab.psu.edu.

--Christina Cowger, Small Grains Pathologist, North Carolina State University

Wheat in the Eastern Shore of Maryland is booting and should be heading out soon. In fact, some of the early-planted wheat is at the early flowering stage already (Information: Mr. Ben Beale, St. Marys County, UMD Extension). Wheat is considered to be at flowering when at least 50% of the heads of a field are beginning to show yellow anthers. Right now, FHB risk appears to be low, so if your barley is heading, or wheat is flowering, you can skip applying fungicides for now. However, the later part of the week is expected to be wet, so keep your eyes out for my risk forecasts if you are not there yet and your wheat flowers in the next few weeks. So far, no major concern from other diseases like powdery mildew or rusts has been seen in wheat in the state. Up in the western part of the state wheat is at second node to flag leaf stage, predictably around 2 weeks away from flowering. So, no need for fungicide application there yet.

--Nidhi Rawat, Small Grains Pathologist, University of Maryland

Barley is beginning to emerge from boot in the southernmost regions of Pennsylvania. Be sure to scout for growth stage as there appears to be a good deal of variability across the region. Risk of scab infection is now increasing with increasing humidity and high temperatures.

Keep a watchful eye on your crop, and if you plan to spray for head scab, target a fungicide application when 50% of the barley stems in the field are fully headed. Caramba, Prosaro, Sphaerex, and Miravis Ace give good control of most leaf and head diseases, in addition to suppressing scab. Spray nozzles should be angled at 30 deg down from horizontal, toward the grain heads, using forward- and backward mounted nozzles or nozzles with a two directional spray, such as Twinjet nozzles.

Continue to visit wheatscab.psu.edu to use the Fusarium Head Blight Prediction Center for estimating your crop scab risk.

--Alyssa A. Collins, Associate Professor, Plant Pathology and Environmental Microbiology, The Pennsylvania State University

Welcome to the wheat and barley flowering season, Maryland! This is the first FHB risk forecast for this season from me, and I will continue to provide you with regular commentaries over the next 6-7 weeks.

Hopefully, you selected a resistant wheat variety for your planting this year after referring to the University of Maryland FHB evaluation of wheat varieties. A good start goes a long way in managing FHB. Unfortunately, for barley, there are no resistant varieties available so far. So, if you have planted barley, keep monitoring for the FHB risk over the next couple of weeks.

Barley is heading in the Eastern shore of the state currently. Because of the mostly dry weather so far, the risk of FHB is minimal right now. Wheat in the Eastern shore of Maryland is either at the jointing stage and should be heading out in a couple of weeks. So right now, wheat is not at a stage vulnerable to FHB. It is important to note that the correct stage for spraying fungicides on wheat is at flowering (when the yellow anthers start to show on the heads), whereas on barley it is at heading (when the heads emerge from the boots). On the western side of the shore in Frederick, Harford, and nearby counties, wheat plants are starting to joint, and are not at a stage prone to FHB infection.

--Nidhi Rawat, Small Grains Pathologist, University of Maryland

Dry weather in recent days is translating into low scab risk in most of NC, and the mostly dry forecast should keep it that way. The exceptions are coastal counties (Onslow, Carteret, Pamlico, Hyde and Dare), where risk is medium or high. Risk projections are for wheat that is flowering, and it is not recommended to spray for scab where risk is low. To monitor risk, go to www.wheatscab.psu.edu.

--Christina Cowger, Small Grains Pathologist, North Carolina State University

Thanks to last week’s rain, the area of medium to high scab risk for NC wheat currently flowering includes much of the southern Coastal Plain and Tidewater region from Robeson through Sampson and Lenoir counties, with heavier risk farther east. With the relatively dry forecast, however, risk will likely decline in the coming days. To monitor risk, go to the web site www.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 resistance of your wheat variety. Risk level is given for wheat flowering on the date selected at the top.

Apply a scab-targeted fungicide if your wheat is beginning to flower and your scab risk is medium to high. 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 (vomitoxin) in a scab epidemic. Miravis Ace, Sphaerex and Prosaro Pro are the most effective in reducing scab and should be applied at early wheat flowering or up to several days later, or about 6 days after full heading in barley.

--Christina Cowger, Small Grains Pathologist, North Carolina State University

The FHB risk forecast model indicates moderate to high risk for the main wheat- producing areas of the state. Wheat growth is primarily in the heading and/or flowering stages, therefore this time is crucial to protect against FHB. Consider making a fungicide application on susceptible varieties if fields in your county are flowering. Check the Wheat Production Guide 2022-2023 https://grains.caes.uga.edu/content/dam/caes-subsite/grains/docs/wheat/… or the 2023 Georgia Pest Management Handbook for FHB fungicide selection. Follow label instructions. Symptoms of frost damage are already showing up in some counties.

--Alfredo Martinez-Espinoza, Professor and Extension Specialist , University of Georgia

NC wheat is mostly at boot to flag leaf stage, with the earliest fields in the south-central part of the state headed but not yet flowering (thanks to Angela Post for observations). FHB risk is estimated for wheat that is at early flowering on that day (www.wheatscab.psu.edu). In south-central NC, risk is currently low; stay tuned, as a rainy period is forecast in the next 10 days. If fungicides for FHB are needed, which is not clear yet, the timing is early to mid-flowering.

--Christina Cowger, Small Grains Pathologist, North Carolina State University

The Fusarium Head Blight Prediction Center provide daily estimates of disease risk for wheat and barley in 35 states. The map displays the probability of severe disease with red and orange areas of the map having the greatest risk. States along the gulf coast are the current focus of the prediction effort because wheat in these areas is likely at vulnerable stages of growth. The risk map is currently showing low risk for most of these areas.

Tips of using the tool: The prediction center uses a wheat growth model to focus the estimates of disease risk on areas where the crop is at or approaching the vulnerable stages of growth for Fusarium infection. Areas in the central and eastern US where the crop is too young, or is already approaching harvest are displayed as a gray color on the map.

The tool shows the disease risk for susceptible wheat varieties for today’s date. You can select earlier assessment dates by clicking on the calendar menu at the top of the risk map. Use the menu button on the upper left to active risk maps for wheat varieties with moderate levels of genetic resistance to Fusarium head blight.

Risk maps based on 2, 4 or 6 days of forecasted weather can help users anticipate future trends in disease risk. These maps are available by selecting the 2d, 4d and 6d buttons to the right of the calendar menu.

--Erick DeWolf, Plant Pathologist, Kansas State University

In most of the southern part of the state, wheat is generally at late booth and/or early heading, but cold temperatures have slowed the crop down some. The effect of recent freezing temperatures remains to be seen. This is especially true in the northern part of the state. Several incidences of powdery mildew have been reported. The FHB risk forecast tool is currently showing “low risk”. However, with rising temperatures, projected rainfall, and the crop soon reaching critical stages for FHB infection, there is a need for continued vigilance. For the northwest part of the state, wheat growth stage is at early booth.

--Alfredo Martinez-Espinoza, Professor and Extension Specialist , University of Georgia