5.1.2 Arrival date of the aphis fly in 2021

During the 2021 aphis fly migration, no unusual events occurred in the Wolnzach area. The first aphis flies were discovered on winter hosts in May. The influx increased until mid-June and then subsided until the end of June.

Figure 5.2: Arrival date of aphis flies in the Wolnzach area, 2017 - 2021