With the predicted showers and thunderstorms for the majority of this week, the weather is expected to be conducive for FHB. Although the FHB risk map currently shows a low risk for head scab, the real risk may escalate in the next few days, especially for the susceptible varieties. Wheat is currently in the flowering stage on the Eastern shore of Maryland, across the state of Maryland. Flowering is when yellow anthers emerge from the wheat spikes. If you have planted a susceptible variety for FHB, you may consider applying FHB fungicides.

If you are planning to apply fungicides for FHB, remember that triazole-containing fungicides (Miravis-Ace, Prosaro, Prosaro-Pro, and Sphaerex) should be used for controlling FHB. They can control other fungal pathogens like powdery mildew, rusts, in addition to scab. Strobilurin-containing fungicides should not be used at this stage. These fungicides do not need to be tank-mixed with another product for spraying. The fungicide products should be applied at the full rate recommended by the manufacturers. Aerial application at a rate of 5 gallons per acre or ground application at 15 gallons per acre with 300-350 um droplet size is recommended. Spray nozzles should be angled at 30-45 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.

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

Dry spring weather has been keeping scab risk low up to this point, however, that may be shifting in some areas of PA who have experienced persistent moist conditions since the first of the month. While the risk map is very helpful to determine average risk across large areas, it may not always reflect precise conditions that occur in pockets of wheat production that are not well-represented by weather stations. If your wheat or barley has been experiencing high humidity for a few weeks, consider a fungicide application for scab at early flowering. If you plan to spray for head scab, choose a labeled triazole-containing product (FRAC 3) like Proline, Prosaro, Prosaro Pro, Miravis Ace, or Sphaerex. Do not use a product that contains any strobilurin (FRAC 11).

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

Head scab risk remains low across most North Carolina wheat-growing regions, including in the scab-prone northeast corner. For wheat planted conventionally, a scab-targeted fungicide is unlikely to be profitable. However, if wheat is planted no-till behind corn and especially if the wheat variety is susceptible or moderately susceptible to scab, a fungicide may be advisable.

Optimal timing to apply a scab-targeted fungicide is early to mid-flowering, or up to a week later. The best timing for barley is about a week after 100% of heads are just emerged. Scab is not effectively managed by applications prior to flowering in wheat and full heading in barley. The most effective fungicides for scab reduction are Miravis Ace, Prosaro Pro, and Sphaerex. Do not apply strobilurin-containing products after flag leaf.

For a wheat variety's scab resistance level, find it at the NC OVT site: https://ncovt.medius.re/wheat. Look under Attributes. Scouting for scab symptoms can be done starting about 2 weeks after flowering and until the wheat starts to dry down.

--Christina Cowger, Small Grains Pathologist, USDA-ARS, NC State University

Wheat fields in Kansas are at or approaching flowering in southeast and south-central counties. The weather is currently highly favorable for FHB (scab) development in these parts of the state. It will be critical to carefully watch fields that are approaching the application window for a scab fungicide (Flowering, Feekes 10.5.1). The highest risk will be in fields of scab-susceptible varieties that are planted back into corn residue. For a reminder about the scab ratings for individual varieties, please refer to the Kansas Wheat Variety Guide: https://bookstore.ksre.ksu.edu/pubs/mf991.pdf.

For more details, please review our recent newsletter on this topic: https://bit.ly/4m3274y

--Kelsey Andersen Onofre, Assistant Professor, Wheat Extension Specialist, Kansas State University

Wheat in the Eastern Shore of Maryland is either flowering (50% of the main tillers showing yellow anthers) or will be flowering in a couple of days. This is the stage when the plants are most prone to FHB infection. Although the epidemiological models are predicting low risk currently, with the rains forecasted starting from this weekend, growers are advised to keep a close eye on the FHB risk over the coming days. In case the risk escalates, the recommended head scab fungicides are Prosaro/ Miravis-Ace/ Sphaerex or Prosaro-Pro. The applications should be made at wheat flowering or within 4-5 days after at full rates prescribed by the manufacturers. Strobilurin-containing fungicides should not be sprayed at this stage. In the northern counties, wheat is booting, and still roughly around 1-2 weeks away from flowering.

--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 due to the dry fall and patchy establishment. Risk of scab infection is low now, but keep an eye on your risk forecast as your crop approaches heading.

The best fungicide application window for barley is from 100% heading up to a week later. If you plan to spray for head scab, choose a labeled triazole-containing product (FRAC 3) like Proline, Prosaro, Prosaro Pro, Miravis Ace, or Sphaerex. Do not use a product that contains any strobilurin (FRAC 11).

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

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

Wheat fields in Kentucky are currently at or fast approaching anthesis (Feekes growth stage 10.51). The risk of Fusarium head blight (FHB) across the state is currently low, but that could change with the forecast of possible rains this week. If the decision to apply a fungicide is made, it is important to use an effective fungicide. Research from the University of Kentucky has shown that several products provide good efficacy against FHB and contamination of grain by associated mycotoxins, such as deoxynivalenol (DON). For specific information about product efficacy, review the publication, "Fungicide Efficacy for Control" of Wheat Diseases available on the Crop Protection Network website (https://cropprotectionnetwork.org/).

--Dr. Carl A. Bradley, Professor and Extension Specialist, University of Kentucky

In Virginia, wheat is currently at varying growth stages across the state. On Friday April 25, many fields were at the boot stage (Feekes 9) or beginning to head (Feekes 10.1 to 10.3), while in some areas and in early maturing varieties heads have fully emerged (Feekes 10.5).

For those choosing to make a fungicide application, the optimal timing for managing scab is at early flowering (Feekes 10.5.1) and up to seven days afterward. Reminder: Do not use products that contain strobilurins (FRAC 11) to manage scab.

Warm, humid, and wet conditions leading up to and during flowering favor infection by the scab-pathogen. As of April 28, 2025, conditions in Virginia are not favorable for disease development in flowering wheat. However, for fields expected to flower in the coming days or weeks, monitor your local weather closely and consult the Fusarium Risk Tool for updates on disease-conducive conditions.

--Douglas S. Higgins, Assistant Professor and Extension Specialist, Virginia Tech Eastern Shore Agriculture Research and Extension Center

Wheat on the Eastern shore of Maryland is heading and should start flowering within a week or so. Wheat in the north-western part (Frederick, Carroll, Hartford counties) is also close to heading or has started heading.

The FHB fungal pathogen infects the wheat plants at the flowering stage (when the yellow anthers emerge from the heads), which is the stage at which the application of fungicides is conducted in wheat. The FHB map currently does not show high risk, especially for a genetically resistant variety. However, keeping an eye on the forecasts and weather patterns over the next few days as your wheat flowers is recommended.

If you are planning to apply fungicides for FHB, remember that triazole-containing fungicides (Miravis-Ace, Prosaro, Prosaro-Pro, and Sphaerex) should be used to control FHB. In addition to scab, they can also control other fungal pathogens like powdery mildew. Strobilurin-containing fungicides should not be used at this stage.

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

Thanks to dry weather, head scab risk is low across North Carolina and surrounding states. This means that for wheat planted conventionally, a scab-targeted fungicide is unlikely to be profitable. However, if wheat is planted no-till behind corn and especially if the wheat variety is susceptible or moderately susceptible to scab, a fungicide may be advisable.

Optimal timing to apply a scab-targeted fungicide is early to mid-flowering, or up to a week later. The best timing for barley is about a week after 100 pct of heads are just emerged. Scab is not effectively managed by applications prior to flowering in wheat and full heading in barley. The most effective fungicides for scab reduction are Miravis Ace, Prosaro Pro, and Sphaerex. Do not apply strobilurin-containing products after flag leaf.

For a wheat variety’s scab resistance level, find it at the NC OVT site: https://ncovt.medius.re/wheat. Look under Attributes.

--Christina Cowger, Small Grains Pathologist, USDA-ARS, NC State University