Forest Resource Protection Forest Health, Insect & Disease Forest Fire Control Staff

Brief Introduction

The Sirex woodwasp is an exotic wood-boring insect that attacks various conifers, notably pine species. The wood-boring larvae, in association with fungi, are most likely to damage red and Scots pine in our area, but may infest white pine, as well. In the United States, the insect is considered particularly threatening to southern pine species.
	Sirex noctillo - adult male

Where is the pest?

Sirex woodwasp was first discovered in the United States in 2002, in Indiana. In 2007, a single adult was trapped in Vermont in Lamoille County. Sirex woodwasp has also been positively confirmed in much of western New York and parts of Pennsylvania, Michigan, and southern Ontario. It has also been introduced inadvertently into New Zealand, Australia, Uruguay, Argentina, Brazil, Chile, and South Africa. Based on its native range in Europe and Asia, it could establish itself in any climate zone of North America where pine occurs.

What’s being done about it?

	What are we doing in Vermont?
	The Vermont Dept. of Forests, Parks and Recreation, the Agency of Agriculture Food, and Markets, and USDA APHIS have conducted detection surveys since 2006. In 2009, traps were deployed in over 150 locations, and no Sirex woodwasps were captured. The 2007 detection remains the only individual of this species ever collected in Vermont.

Recommendations

• Examine Scots, red and Eastern white pine trees for wilting, discolored foliage, resin beads or dribbles at egg laying sites, larval galleries tightly packed with very fine sawdust, and round exit holes 1/8 to 3/8 inch in diameter.
• Thin pine stands to maintain optimal stocking. Sirex woodwasp is more likely to damage slow-growing trees.
• Stay abreast of current quarantine regulations on the movement of pine wood products and nursery trees.

For More Information

VT Department of Forests, Parks & Recreation, May 2010