
IN ET NYn I NI by Jerry Carlson and Karin Verschoor Much as a virus or worm can infecl an entire computer network, tiny insect invaders are threatening to wreak havoc on New York's forests. Two wood-boring insects, the sirex woodwasp and the emerald ash borer, have been spotted in or near New York State. Unwelcome visitors, both species are capable of quickly destroying an entire patch of forest As such, these insects are the focus of intensive research and monitoring by the United Slates Department of Agriculture, the New York Department of Agriculture and Markets, and the New YorX State Department of Environmental Conservation (DEC). tree, and infect the tree Sirex Woodwasp with a rungus which softens and modifies A large, wood-boring wasp. the sirex woodwasp is a the wood so the larva devastating pest of pine trees. It is native to ~:urope can feed on it. The toxin flnd Asia, and has already impairs the tree's natural destroyed millions of pines in ability to fight ofT the Australia. South America and An exomple of on infected tree fungal infection, and the SouLh Africa. Believed to have portion of the tree above the injection site quickly dies. come into the U.S. in wooden' Because of the danger that sirex wood wasps pose packing material such as crates to New York's pines, D(!:C is asking the public to or pallets. this woodwasp's first report any sigbtings of the insect or its damage. Away known North American occur­ from its native Europe, these wasps have no natural rence was in Oswego County enemies nnd so cou ld spread unchecked if not detected in 2005. Since t.hen. it has been early enough. Signs of possible inrestation in pines found in Onondaga, Wayne, include dying needles in the tree crown, or sudden Sirex Woodwosp Seneca and Cayuga counties, h'ee death for no obvious reason. If you suspect a tree (fe male) Adults: 2-1 " long. Thick bodied; no and has just been detected in may be infected. look on the tree trunk -Wasp" woist. Females: southern Canada. for exit holes. often mnrked by ooz- solid block body wi lh Sirex wood wasps are solitary ing resin. Woodwasp exit holes will spear-like ovipositor black wasps with brownish be randomly scattered on the tree, in Males: wide oronge contrast to regular rows of holes made band on abdomen wings and orange legs. Females lay their eggs in pine tree by sapsuckers. Also, keep an eye on any trunks. where the eggs hatch into white, wood-boring cut wood with tunnels throughout the t grubs. The grubs then tunnel through the tree, eventu­ wood. The presence of white larva with ally emerging as adults through holes measuring 1/4 a distinctive back spine or "horntail" to 3/8 inch in dinmeLer. During the egg-laying process, on the real' indicates a sirex wood wasp De lo il of the infestation. chorocteristic back female'woodwasps also inject a toxin to weaken the ' horntail' spine borers, who tend to attack city and suburba n trees. Emerald Ash Borer Affected ash first show dieback in the crown. and may have cracks in the bark overactive feeding Native to Asia, the e merald ash borer is a s mall, tunnels. As the inner bark is destroyed, the tree dies colorfu l wood-boring beetle tha t has already destroyed back and may grow spn)uts from the middle or the millions of ash trees base of the trunk. Called epicor mic sprouting, this is a in the U.S. 1t was first. last-ditch effort for Sllrvival by a mortally stressed tree. detected in Michigan .if you spot these sympt.oms, look closely at the tree in 2002, and is now causing problems in Ohio and Ontario, Canada as well. Like the sircx woodwasp, Emerald Ash Borer the emerald ash borer Adults: 2' long Slender, golden­ is thought to have green iridescent beetle with large entered this country compound eyes via shipping materiaL WhiJe it has not yet Damage created by an Emarald Ash Barer been spotted in New York. it poses a real threat to the state's ash trees. trunk for cracked 01" loose bark and borer holes that a re During summer, adult e mera ld ash borers emerge characteristic of e merald ~sh borer activity. Dieback fro m small "D"-shaped holes in ash tree trunks and a nd epicormic sprouting alone could also be signs of begin eating the tree's leaves. They soon begin to "ash yellows." a disease that has been killing many ash disperse in search of additional food and sujtable trees in New York. mates, flying in short spurts of up to 50 feet. though Jeny Carison is a member of the Steering Committee fOl" the sometimes traveling miles to find host trees. Following GoverrlOf" Inyasive Species Task Force, is a Research Scientist with DEC's mating. female e merald ash borers lay their eggs in the Fore$t Health Program. Kari n Verschoor WDfks in DECs Division of Lomb and Forests crevices on the trunks of ash trees. The larvae burrow under the bark and eat their way through the cambium ''''''''I SIon.iIaw Konol .... ,. """... Fot... Reoeo<ch I..... "''''· 2 OEC p/>OIO (the live inner bark) leaving winding, "s"-shaped tun­ J fI:.uIo~. I............ Noc....-oI do fotro::>Iogoa ~ . nels. These cause the trees to lose their ability to trans­ • SIon.okrw Ko ....... PoIoth I'o<eII ~ 1.-...0· S _ W Smolh. IJSD,O. ~151'f'O- port nutrients, and so they slowly starve. • """"'"' PfO"!(Io<Ibr -~_""'" To combat the spread of this pest, strict quarantines hnve been implemented in affected areas of Michigan,. prohibiting the movement of any ash trees, ash wood and a ll hardwood fil'cwood from a quarantine area. Unfortunately, in n violation of the quarantine, a nursery shipped more than toO uninspected ash trees to Maryland. A year a fte r these trees were planted, e merald ash borers were discovered in some of the trees. Maryland quickly set up a qua rantine and removed not only the suspect trees, but also 1,000 potential host trees. Today, the infestation a ppears to have been stopped. but scientists will monitor the area for a t least three more years. New York State's ash trees a re a waiting feast for the e merald ash borer. In the past 20 years, hybrid ash have been widely planted along streets and used in commerciallandscnping such as mall parking lots. Since these trees are generally somewhat stressed and also perfectly spaced for easy beetle night from tree to tree, thvy make pe rfect targets for the emerald ash lIepr",'~ from lilt Nrl<' I'ark SI"lp ('onM'rvalionisl. April 2006 .
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