In spring, spores are produced mainly from barley residue left on the soil surface from the previous year. Spores produced on infected leaves are transported to other barley plants by rain drops and wind. Scald can attack a barley plant at any time but levels of infection are usually most severe just before and during heading. The significance of scald-infected seed as a source of disease spread in barley is not well understood. Damage Description Scald is primarily a foliar disease but is also found on leaf sheaths and glumes.
Spots often join and kill the entire leaf.
Yield losses in Alberta have been calculated at 2.4 per cent, although losses in particular fields may exceed 25 per cent. Losses are due to a decrease in photosynthetic area on the flag and second leaves resulting in reduced seed weight. Severe scald infections can cause damage that resembles black point but is not confined to the embryo end. In general there is a direct relationship between the amount of disease present on upper leaves of cereals and the resulting loss in grain yield. The top two leaves of the cereal plant supply most of the energy required to produce well-filled grain.