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?
Forest products industries in some areas are receiving recommendations to
minimize accidental transport of the pest out of infested areas. At this point,
there is no viable control program for this invasive insect, but regulatory
options may be necessary to limit the spread. A state quarantine is already in
place that restricts the movement of pine products into North Carolina. A
federal quarantine is being considered to reduce the artificial spread of the
insect in pine products. If it is approved, it will restrict the movement of pine
sawlogs, pulpwood, log home components, lumber, bark, and chips, as well as
nursery trees from at least six Vermont counties. A nematode that attacks
Sirex woodwasp larvae is being investigated for biological control.
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 have been captured. Surveys have included pine trap trees, as well as deploying baited and unbaited traps. At this time, however, methods being used are not considered particularly effective in detecting populations of Sirex woodwasp.
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.
This insect will have a major impact if it spreads into Vermont. The sooner we find new infestations, the better our chances of slowing its spread to other trees nearby or to other areas, and of eradicating it where it has been detected.
If you suspect this pest occurs in your area or for more information, contact the Forest Biology Lab at 802-241-3606, or
Windsor & Windham Counties
Springfield (802) 885-8855
Bennington & Rutland Counties
Rutland (802) 786-3851
Addison, Chittenden & Grand Isle Counties
Essex Junction (802) 879-6565
Orange & Washington Counties
Barre (802) 476-0170
Lamoille & Washington Counties
Morrisville (802) 888-5733
Caledonia, Orleans & Essex Counties
St. Johnsbury (802) 751-0110
VT Department of Forests, Parks & Recreation, September 2009
![Vermont Division of Forestry [photo]](../img/banner_protection.jpg)
