Onions in my Cereal
Something I do not see very often in a cereal crop is Wild garlic (Allium vineale) and wild onion (Allium canadense) these are the latter.
Both are winter perennials, which emerge in late autumn from underground bulbs growing through the winter and into spring.
Unfortunately, pre emergence herbicides are not the best at control of these species
Underground bulbs persist in the soil for years. While both have thin, green, waxy leaves, those of wild garlic are round and hollow, while those of wild onion are flat and solid. One of the characteristic that makes control difficult is that both have a thin, glossy leaf to which herbicides don’t readily adhere.
Historically treatment with a mixture containing 2,4-D, dicamba, and mecoprop can provide control of wild garlic and wild onion where repeat applications can be made.
Nowadays there are thankfully better options.