NC wheat ranges from jointing in the west to boot stage in the south and flag leaves out in the east. Wheat is vulnerable to scab infection at flowering. Flowering will take place mainly from mid-April through the first week of May. The forecasting tool estimates scab risk for wheat flowering on the day that is selected (www.wheatscab.psu.edu). High relative humidity and mild temperatures increase risk. If risk is moderate to high, the best time to apply fungicide to wheat is early- to mid-flowering or even a few days later. In winter barley, the best time for a scab-targeted fungicide is around 6 days after full heading.

Products with highest efficacy against scab include Miravis Ace, Sphaerex and Prosaro Pro. Products containing strobilurins should be avoided. If small grains are planted no-till into corn debris and especially if the variety is not moderately resistant, it is advisable to apply a fungicide even if forecasted risk is low.

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