Not considered a nursery production pest, March flies, Bibio albipennis and Bibio xanthippes, are found on occasion in large numbers in production areas. These flies are dimorphic, the males and females differing in appearance. They are often found joined together. This gave rise to the common name of lovebugs for a similar species, Plecia sp., found in the south. For our area, March fly is a misnomer as they are usually found in April and May in Western Oregon.