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the first group are like steak to ALB while trees in the second group are like hamburger.All are trees that the ALB can complete its lifecycle in. #4."ALB is not a pest in ALB Adult Full-grown ALB larva The much smaller EAB adults are very good fliers and they easily dis- perse.While ALB adults are relatively good fliers, they take flight much less frequently compared to EAB, perhaps because their large bodies require much more energy to launch and remain airborne.Thus,ALB tends to stay and continually re-infest trees until the trees die and are no longer able to support a new generation.As a result,ALB does not spread very fast from tree to tree compared to EAB. #2."ALB behaves differently in each North American infes- tation."This myth is related to a misconception regarding the true nature of the genetic testing used to reveal that ALB infestations in the five states where ALB has been discovered came directly from Asia.Each North American ALB infestation most likely started with only a few beetles, thus all the progeny are closely related.However,this genetic bottleneck produced by the "founder effect" imparts only slight genetic variability; about the same that is used to determine paternity in humans.The variability is not large enough to produce truly different bee- tles.Thus,research conducted on beetles in one location is applicable to beetles in other locations. #3."ALB only infests maples: no need to worry about other hosts."This myth may have flowed from our emphasis on highlighting maples as a primary target for the beetle.While maples are indeed at the top of ALB's food menu, the beetle's complete table fare comprises trees belong- ing to 13 plant genera including Acer (all maple species),Aesculus (horsechestnuts and buckeyes), Ulmus (elms), Salix (willows), Betula (birches), Platanus (Sycamore / Planetrees), Populus (Poplars); Albizia (Mimosa),Cercidiphyllum (Katsura),Fraxinus (ashes), Koelreuteria (goldenraintree), Sorbus (mountainash) and Celtis (Hackberry).While the first six in this list of genera are gener- ally considered the trees most commonly attacked byALB, all of the trees in this list can be attacked and killed byALB;trees in www.arborage.com #5."ALB does not kill trees."This myth most likely arose from a misunderstanding based on observing the rapid tree-killing behavior of EAB.EAB attacks ash trees,which are "ring porous,"water and nutrients are only transported through the outermost xylem ring.EAB is a phloem feeder;however, as the larvae gain size, they start etching the outermost xylem ring.Consequently, trees may die quickly as EAB larvae girdle trees by consuming the phloem and etching the single functioning xylem ring. ALB infests some ring porous trees;how- ALB larva in xylem ever, maples are most commonly attacked and maples are "diffuse porous,"water and nutrients are carried by four to five of the outermost xylem rings.Although ALB lar- vae bore into the xylem, their tunneling causes less disruption of the xylem vascular flow compared to damage caused by EAB in a ring porous tree. In the end, the ALB larval damage does kill trees, but infested trees may linger for many years giving the false impression that they are not being killed.Of course,as they linger,the trees are a constant source of new beetles. #6."Insecticides are highly effec- ALB eradication, tree removal tive in controlling ALB: they make treated trees immune to the beetle." This misconception may be related to the success that can be achieved with using insecticides to protect ash trees from EAB. Again, EAB and ALB are like apples to oranges.Although EAB is not targeted for eradication, ash trees can be successfully Arbor Age / July/August 2012 19 EAB adults its native China." In fact,ALB is a major pest in its home territo- ry, causing widespread mortality to poplar,willow and elm.Much of the damage in China occurs on street trees, trees in windbreaks and hedgerows, and trees in manmade forests and plantations.Many of the plantations are dedicated to growing trees that are processed into wood packing material including crates and pallets. Globe-trotting by the beetle has in the past stemmed from larvae,pupae,and newly devel- oped adults hitchhiking inside such packing materials.Thankfully, regulations to prevent the import of this and other non-native plant pests and diseases now have a much greater "bite"than in recent years in terms of fines and penalties.