The bronze poplar borer, A. liragus Barter & Brown, breeds in poplar in 
Canada and southward in the United States to Pennsylvania and Arizona. Adults are 
blackish with deep-green reflections and are about 7 to 12 mm long. Overmature or 
defective trees and young trees suddenly released by the removal of dominant trees 
are most often attacked; however, felled, topped, or girdled trees and trees damaged 
by Saperda calcarata Say and infected by the fungus Hypoxylon mammatum 
(Wahl) Miller are also attractive. Infestations in standing trees usually begin in the 
crown and move downward. 
Adults are present during a period of several weeks in the summer and feed on the 
leaves of poplar. Eggs are deposited in bark crevices and the larvae feed in the 
cambial region, excavating long tunnels that zigzag back and forth in a compact 
manner. The larvae feed for two seasons in Ontario before becoming mature (63). 
Woodpeckers took heavy tolls in mature larvae, pupae, and, presumably, adults in 
standing trees in Ontario. 
Agrilus horni Kerremans occurs in Ontario and the northern tier of Eastern 
States, and breeds in young, apparently healthy aspen suckers, especially quaking 
aspen, some of which it girdles and kills. Adults are almost identical to those of the 
bronze birch borer except for shorter ovipositors in the females. 
Eggs are deposited on the smooth bark at the base of aspen suckers. The larvae 
bore into the bark and tunnel downward and out along large roots, gradually 
working their way through the bark to the cambium region. Once here, they turn 
around and tunnel back toward the main stem, making spiral galleries that encircle 
the roots and which may be continued up the trunk for 6 to 10 cm. Pupation takes 
place in a cell in the center of the stem, and the life cycle requires 2 years. Damage 
appears to be most severe in sparsely stocked stands or in stands growing on poor 
sites (937). 
Agrilus arcuatus torquatus LeConte, the hickory spiral borer, has been re- 
corded from New York, Ohio, North Carolina, and Mississippi, apparently favor- 
ing hickory and pecan, but also infesting many other hardwoods. It, or a closely 
related species, has been observed attacking young oaks and other hardwoods in the 
Piedmont of the South (74). Adults are about 8 mm long. Males have a greenish- 
bronze head and thorax, purplish-black elytra, and brassy underparts. Females are 
completely bronze. 
Adults appear from May to July and feed on the leaves of their host, making large 
irregular holes. Eggs are deposited singly on the bark surface or on terminals or 
twigs, usually near the base of a small shoot of the current season’s growth. The 
larvae feed downward beneath the bark during the summer, and during the fall they 
sever the wood by constructing a spiral burrow. The following spring, they continue 
to feed beneath the bark, constructing long, irregular tunnels that deeply engrave 
the wood. When they are full grown, they make a second transverse spiral cut 
around the wood, working first toward the pith and then out again to the phloem, 
leaving the bark intact. Then, they mine upward in the phloem for 2.5 to 5 cm and 
construct pupal cells entirely within the pith. Two years are required to complete the 
life cycle (159). This species is often very destructive of hickory seedlings in the 
South. 
Agrilus acutipennis Mannerheim, the spotworm borer, has been observed 
attacking overcup oak in Louisiana and Arkansas (876). Eggs are deposited on the 
bark. The larvae bore through the bark and then excavate patches of inner bark up to 
12 mm in diameter. Later, they enter the wood and tunnel spirally upward in the 
outermost growth ring. Pupation occurs within the tunnel and the life cycle requires 
2 years (1133). 
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