 Curtis Young reported that the elm flea weevil eggs have begun to hatch. The eggs had been and continue to be laid by the overwintered adult weevils into the main mid-rib veins of the host elm leaves. The adult females chew a small hole in the vein and deposit a single egg into the hole. Even though the leaves of the host elms have been expanding very slowly, the weevils have been attacking them almost as soon as they are exposed. Many small leaves are showing extensive deformation as a result of this oviposition activity. Some of the earliest laid eggs have hatched and the young larvae are producing serpentine mines toward the tips of the leaves. In some cases, blotch mines have already been constructed by the older larvae. First, second and possibly third instar larvae are present in the mines. The larvae range in color from a light leaf-green color of the earliest instars to white of the older larvae. The larvae are legless and cone-shaped, broadest at the head-end. All stages of the elm flea weevil are relatively minute and are less than 1/8" in length. Yet defoliation and mining can be extensive on elm hosts. Curtis reports the greatest activity is on Siberian elms (Ulmus pumila) but has also seen the weevil on other species including the true Chinese elm (U. parvifolia). Currently, only eggs and first instar larvae are present on the Chinese elm. Part of the reason for the difference between the hosts in the development of the weevil is the difference in the foliage development. The Siberian elm leaves are much further along in their expansion. The Chinese elms lag behind by at least a week. Joe Boggs reports not being able to find the critter in the Cincinnati area. Thus, BYGLers are curious as to what the BYGL readers are seeing with this insect. Please drop us a note by e-mail to Curtis Young as to what you see on elms in your area at:
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. For more information, see: 
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Last Updated ( Thursday, 08 May 2008 20:40 )
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BYGL 
