Adult: Adults emerge from mid May to early June, depending on local conditions. According to Cappaert et al. (2005) “Adults live for around 3 to 6 weeks, with peak activity from late June to early July in southeastern Michigan. Adults feed on ash foliage for 5 to 7 days before mating, and females feed for another 5 to 7 days before oviposition.”
Egg: Eggs are laid in bark crevices or under bark flaps (Bauer et al. 2004a in Cappaert et al. 2005) and hatch in seven to nine days (Nomura 2002).
Larva: Studies in southeastern Michigan revealed that larvae hatch in late June or early August (Cappaert et al. 2005). According to Scarr et al. (2002) “After hatching, first-instar larvae initially bore through the bark to feed on the phloem and eventually feed on the outer surface of the sapwood as they grow. Growing larvae as they feed form tunnels that are flat and wide, and zig-zag (S-shaped) throughout the bast and outer sapwood. Tunnels may be as long as 9 to16 cm and they are filled with brownish sawdust and frass. In Michigan, U.S.A. tunnels are reported to be between 20 and 30 cm long. Most of the tunnels tend to occur in the basal portion of the tree trunk up to a height of 1.8 m.” Cappaert et al. (2005) report that “As larvae feed they excise serpentine galleries through phloem, until cessation of feeding in October or November. Larvae then excavate a ~1cm deep cell in the sapwood or outer bark where they overwinter as prepupal larvae. Larvae pass through four instars”.
Pupa: Cappaert et al. (2005) report that “Pupation begins in mid-April and continues into May. Adults emerge approximately 3 weeks later.” Pupal development is variable according to humidity and temperature. After pupae transform into adults in the spring, the beetle takes 1 to 2 weeks before it emerges through D-shaped exit holes 3-4 mm wide (APHIS-USDA 2008).
Principal source: Smitley and McCullough, 2004 How Homeowners Can Protect Ash Trees From the Emerald Ash Borer in Southeastern Michigan.
Compiler: National Biological Information Infrastructure (NBII) & IUCN/SSC Invasive Species Specialist Group (ISSG)
Review: Dr. Deborah G. McCullough Associate Professor Dept. of Entomology and Dept. of Forestry Michigan State University USA
Publication date: 2006-08-14
Recommended citation: Global Invasive Species Database (2024) Species profile: Agrilus planipennis. Downloaded from http://www.iucngisd.org/gisd/speciesname/Agrilus+planipennis on 02-11-2024.
Nomura (2002) reports that damage consists of, \"D-shaped exit holes along the lower bole surface are clear signs of buprestid beetle activity, however, careful examination is required as these are very cryptic. Frass filled, zigzagging tunnels about 6mm wide at the sapwood/bast interface are signs of A. planipennis feeding. Callus tissue produced by the tree in response to larval feeding may cause vertical splits 5 -10cm in length to occur in the bark above a gallery.\" MDNR (2004) states that, \"Infested trees exhibit top-down dieback, with 1/3 to 1/2 of branches dying the first year and the remaining canopy dying the following year. This is often followed by a large number of shoots arising below the dead portions of the trunk. Borers make a small (1/16 inch diameter) \"D\"-shaped hole when entering the tree and several distinct \"S\"-shaped tunnels may be present under the bark. Trees may also exhibit 5-10cm vertical splits in the bark in response to larval feeding.
A. planipennis attacks ash trees in the genus Fraxinus. All North American ash species that occur within the current EAB range have been killed by EAB, including white ash (F. Americana), green ash (F. pennsylvanica), black ash (F. nigra), blue ash (F. quadrangulara) and pumpkin ash (F. profunda) (Lindell et al. 2008). Attacks on non-ash species have not been observed in North America to date, but there is concern that other species could be vulnerable. If A. planipennis host range extends beyond Fraxinus spp., the impacts of this invasive pest in North American forests would increase dramatically. Anulewicz et al. (2008) assessed A. planipennis landing rates, oviposition and larval development in a number of North American tree species. They found that “although A. planipennis adults will occasionally land on and oviposit on logs and trees of non-ash species, A. planipennis larvae did not successfully develop on anything other than Fraxinus species” (Anulewicz et al. 2008).
The three main ash species in Europe are F. excelsior, the most widespread species, and F. ornus and F. angustifolia. Nothing is known of the susceptibility of these to A. planipennis, so evaluating the resistance of these European species should be a research priority. F. excelsior is a common forest and urban tree used for timber, flooring, tool making and for its medicinal properties (FRAXIGEN 2005 in Baranchikov et al. 2008). All three species are important components of forest ecosystems in Europe and “their disappearance would have serious consequences for native biodiversity and ecosystem services” (Baranchikov et al. 2008).