LECONTE'S SAWFLY, 1 AN ENEMY OF YOUNG PINES 



By William Middleton 



Scientific Assistant, Forest Insect Investigations, Bureau of Entomology, United States 



Department of Agriculture 



INTRODUCTION 



The following paper on Leconte's sawfly, Neodiprion lecontei (Fitch), 1 

 consists of a detailed description of the various phases of this insect and 

 summarizes the notes on the life and seasonal history. A few notes on 

 the economic importance and the means of control are added. 2 



In describing the larva special care has been taken, and such new terms 

 as have been introduced are carefully explained and illustrated. It is 

 believed that by the introduction of these terms it has been possible to 

 give a more nearly accurate description of the larva and that this termi- 

 nology will aid in the preparation of descriptions of larvae belonging to 

 allied groups. The terminology here used is the same as that applied 

 to Pteronidea ribesii (Scopoli), Neodiprion lecontei, and other sawfly 

 larvae in a paper ready for publication, and for the reasons therein con- 

 tained and to avoid possible confusion it seems advisable to continue the 

 use of the same letters to designate the same body areas. 



Because of the feeding habits of the larva, Leconte's sawfly is an impor- 

 tant enemy to young pine trees in the eastern part of the United States. 

 It is especially injurious to nursery stock. While this paper deals briefly 

 with all of the phases of the insect, more detailed accounts of its life and 

 seasonal history, the damage done, and the means of control have been 

 reserved for future publications of a less technical nature. 



DESCRIPTIONS 

 ADULTS 



FEMALE (pl. 88, a) 



Length of female 6 to 9.5 mm. Labrum narrowly rounded apically, the surface 

 shining and slightly concave; clypeus broadly subangulately emarginate, apical mar- 

 gin broadly depressed, the basal part convex, with small, poorly-defined punctures; 

 supraclypeal area flattened; antennal fovese large, shallow, connected with the deep 

 supraclypeal fovese; lateral foveae large, circular, deep; middle fovese and ocellar basin 

 shallow, poorly defined; postocellar area usually well defined, convex, wider 



1 Order Hymenoptera, suborder Chalastogastra, family Tenthredinidae, subfamily Diprioninae. 



2 All the rearing and experimental work on which this paper is based was carried on in the insectaries 

 and nurseries of the Eastern Field Station of Forest Insect Investigations, Bureau of Entomology, located 

 at East Falls Church, Va. The work has been done under the direction of Mr. S. A. Rohwer, specialist 

 in Forest Hymenoptera, and the author is indebted to him for the descriptions of the adults, helpful 

 suggestions, and many of the observations here recorded. Plate 88 was drawn by Miss Mary Carmody, 

 Plate 92 was photographed by H. B. Kirk, and Plates 89 to 91 were drawn by the author. 



Journal of Agricultural Research, Vo1 - :KX - No - IO 



Washington, D. C. Feb - *. I921 



I Key No. K-91 



(74l) 



