By Pierce Paul, Ohio State University Extension
Wheat is, or will soon be, flowering in parts of central and northern Ohio. After a relatively slow start to the season, several days of warm weather caused the crop to advance, reaching anthesis (Feekes 10.5.1) a few days earlier than usual in some locations. Feekes 10.5.1 is the growth stage at which wheat is most susceptible to infection by the fungus that causes head scab and produces vomitoxin.
However, according to the FHB risk tool (www.wheatscab.psu.edu), fields across the state are currently at low risk for head scab. This is likely because of the relatively low temperatures we have experienced over the last few days. The tool indicates that the risk for head scab development is low in fields flowering on May 23, and assessments based on 2 to 6 days of forecasted weather suggest that the risk will continue to be low into the weekend as more fields reach anthesis. Continue to look at the tool as more fields reach anthesis; the risk could change quickly as it warms up, particularly if the warmer weather is accompanied by high relative humidity and/or frequent rainfall.