Agrilus planipennis is spreading in Central Russia
In the European part of Russia, the presence of Agrilus planipennis (Coleoptera: Buprestidae – EPPO A2 List) was first reported in 2007 (see EPPO RS 2007/067) in the city of Moscow, although there are indications that it was already there in 2003 and had probably been introduced in the late 1990s. At present almost all ash trees (Fraxinus pennsylvanica, F. excelsior) in Moscow and its vicinity have been killed or severely damaged by the pest.
In 2012, A. planipennis was discovered in the oblasts of Tula, Kaluga, and Smolensk. In spring and summer 2013, a survey (Orlova-Bienkowskaja, 2013) was conducted in 22 localities (and included 2719 F. pennsylvanica and 115 F. excelsior trees) in the European part of Russia to detect damage caused by the pest. Damaged trees with emergence holes were found not only in the Moscow oblast, but also in Konakovo (Tver oblast), Michurinsk (Tambov oblast), Tula, Kaluga, Orel, Yaroslavl and Voronezh. Observations made indicate that the beetle probably needs more than 1 year to complete its life cycle in these areas. In all inspected localities of the Moscow oblast, as well as in the city of Konakovo (Tver oblast), most ash trees had already been killed by A. planipennis. Most ash trees in Kaluga, Orel, Tula, Yaroslavl, Michurinsk and Voronezh appeared healthy, but groups of damaged and dying trees with characteristic D-shaped emergence holes were observed. The pest now occupies a large area of at least 150 000 km² around Moscow (250 km to the West of Moscow, 230 km North, 250 km East, 460 km South).
In another study (Straw et al., 2013), similar observations have been made (although the estimated invaded area is slightly smaller). It is noted that over the last 4 years, the pest has been spreading at a rate ranging from 30 to 40 km per year. High rates of spread have also been observed along the motorways west and south of Moscow, suggesting a strong influence of human-assisted transport. It was also noted that F. pennsylvanica, a highly susceptible host, had also been widely planted along these main roads which has probably facilitated rapid spread. In this part of Russia, the local movement of firewood is not thought to be a significant factor because mainly birch and conifer are used for firewood. Considering such a rapid rate of spread, it has been estimated that that A. planipennis might reach the western border of Russia around 2020.
Both studies concluded that A. planipennis presents a serious threat for ash trees in Europe, and noted that as low population densities of the pest are particularly difficult to detect, it cannot be excluded that isolated populations have already spread outside what it is currently considered as the invaded area in Central Russia.
Sources
Orlova-Bienkowskaja M (2013) Ashes in Europe are in danger: the invasive range of Agrilus planipennis in European Russia is expanding. Biological Invasions. doi: 10.1007/s10530-013-0579-8.
Straw NA, Williams DT, Kulinich O, Gninenko YI (2013) Distribution, impact and rate of spread of emerald ash borer Agrilus planipennis (Coleoptera: Buprestidae) in the Moscow region of Russia. Forestry. doi: 10.1093/forestry/cpt031