During oviposition, the female wasp lays two eggs with or without a mucoid substance and a symbiotic fungus for the larvae to feed on once they hatch.

The sting is connected with the mycetangia, which are special organs on the abdomen, where the female stores the oidiae (asexual fungus spores), from broken segments of hyphae.

[10] The native habitat of the European woodwasp is the temperate Palearctic realm, ranging from Maghreb over Europe, Siberia, and Mongolia, to the Kamchatka Peninsula.

The species has reached other continents, such as Australia, South Africa and North America, through the export of timber and firewood.

While invasion was prevented in North America for a long time, the European woodwasp established itself in New Zealand around 1900.

There, it contributed to massive pine declines in the first half of the 20th century, spreading to Tasmania in the 1950s and then to the Australian mainland.

Since 1980, it has reached pine plantations in Uruguay, and later also Argentina, Brazil and Chile; it was found in South Africa in 1994.

The population increased in the Great Lakes area from 2004 on; the species had reached Vermont, New York, Pennsylvania, Ohio, and Michigan by 2009.

[13][14] Subsequently, forestry authorities intensified their pest control methods and additionally started education campaigns, such as warning not to transport firewood over large distances or to store it too long.

Remote locations, such as the Horn of Africa, may be spared from the European woodwasp, providing the area is controlled.

[15] The flight time of the adults or imagines begins in the late summer to early autumn, but the date depends on the region and climate.

When a tree is stressed through dryness or exterior injuries, the compounds pervade osmotic barriers and escape from the bark.

The tree can only ward off the infestation if it floods the boreholes with resin or halts the fungus by producing a wall of polyphenols.

The European woodwasp is, together with S. juvencus and S. nitobei from eastern Asia, one of three symbionts of the fungus that in the first instance benefits from its vector function.

Additionally, the wasp creates the optimal conditions for the infestation through the fungus by drilling into the underlying wood layers and weakening the host tree.

In the Southern Hemisphere and in North America, the wasp attacks exotic and domestic pine species, generally in plantations.

[16] Unlike any other species of Siricidae, the European woodwasp can damage relatively healthy trees so heavily, they die back.

[16][17] Because the wasp larvae and the fungus need living wood, the European woodwasp does not infest dry or dead timber.

Infestation damage can be divided into four categories or phases, depending on whether it is caused by the imago, fungus, larvae or secondary parasites.

A phytotoxic secretion of the wasp impairs metabolism in the shoots and needles, causing loss of water balance.

Tip dieback begins with the needles becoming chlorotic and changing from green to yellowish-red, finally turning completely brown over a three- to six-month period.

[6] During this process, fungal spores germinate in the boreholes, a reaction caused by the dryness of the tree, creating an appropriate environment and an entry for air.

These include Ibalia leucospoides (Ibaliidae); Schletterius cinctipes, Megarhyssa nortoni (Ichneumonidae); and Rhyssa persuasoria.

The parasites locate host larvae hidden in the wood using their antennae to detect cues, including the smell of leaking drill dust or fungus mycelium, weak vibrations, or differences in temperature.

The related species B. wilsoni has a similar effect, but as it also lives parasitically with the genus Rhyssa, it is not used for pest control.

[4][29] As a consequence of forest damage in Australia and New Zealand, wood imports to those countries have been required to be certified free from living sirex larvae.