Sirex noctilio Fabricius (Sirex woodwasp )

 


Vicky Klasmer,
Instituto Nacional de Tecnologia Agropecuaria

 

 

 

Class: Insecta

Order: Hymenoptera

Family: Siricidae

Synonym(s):

Adult Description: Woodwasps (or horntails) are large, robust insects, usually 1.0 to 1.5 inches long. Adults have a spear-shaped plate (cornus) at the tail end; in addition females have a long ovipositor under this plate. Body dark metallic blue or black; abdomen of males black at base and tail end, with middle segments orange. Legs reddish-yellow; feet (tarsi) black; males with black hind legs. Antennae entirely black. Positive identification of S. noctilio needs to be confirmed by an insect taxonomist.

Larva Description: Larvae are creamy white, legless, and have a distinctive dark spine at the rear of the abdomen. More than a dozen species of native horntails occur in North America. No keys to identify woodwasp larvae to the species level have been developed

Host Plant: Monterey pine (P. radiata) and loblolly pine (P. taeda). Other known susceptible pines include slash (P. elliottii), shortleaf (P. echinata), ponderosa (P. ponderosa), lodgepole (P. contorta), and jack (P. banksiana).

History: This woodwasp was introduced inadvertently into New Zealand, Australia, Uruguay, Argentina, Brazil, Chile, and South Africa. In these Southern Hemisphere countries, sirex woodwasp attacks exotic pine plantations, and it has caused up to 80 percent tree mortality. Most of the plantations are planted with North American pine species.

Biology: Scientists estimate that S. noctilio can spread at least 25 miles per year naturally.

Ecological Threat: In these Southern Hemisphere countries, sirex woodwasp attacks exotic pine plantations, and it has caused up to 80 percent tree mortality. Most of the plantations are planted with North American pine species.

US Habitat: Forested areas especially in areas of pines.

Distribution

Native Origin: Sirex woodwasp is native to Europe, Asia, and northern Africa.

US States: Twenty four counties in upstate New York and two counties in Pennsylvania have positively confirmed the presence of this pest. Not currently found in Texas.

If you believe you have found sired woodwasp, please report this species.

Texas: Not currently found in Texas.

Resembles: More than a dozen species of native horntail wasp.

Management: Currently no management. Collect and submit any suspect woodwasps to your county extension or state Department of Agriculture office.

Text References

Dennis A. Haugen & E. Richard Hoebeke. 2005. Pest Alert: Sirex Woodwasp - Sirex noctilllio. USDA Forest Service. Accessed 05 January 2012: http://na.fs.fed.us/spfo/pubs/pest_al/sirex_woodwasp/sirex_woodwasp.htm.

Data Source

Bugwood.org

Last Updated: 2013-12-05 by HTG