REPORT OF COMMITTEE ON PUBLICATION 247 



The Pupa. 



When the larva is full grown and ready to change to the pupal form, 

 it leaves the root and ascends in a more or less direct course to within about 

 an inch of the surface of the ground. Here it constructs a rough, elongate 

 cocoon, of an average length of about one inch. The cocoon is composed 

 outwardly of grains of earth mixed with the borer's excrement and is lined 

 with tough silk. The borer transforms within this cocoon to a pupa of 

 dark brown color with several narrow yellow bands encircling the abdomen. 

 When ready to change to the adult insect the pupa works half its length out 

 of the cocoon and the moth escapes through a slit in the back. 'The discarded 

 pupa case is left with one end inserted in the cocoon and the other projecting 

 a short distance above the ground. The pupa stage covers a period of four 

 or five weeks. 



The Adult. 



The adult grapevine root-borer is a handsome moth, the sexes of which 

 differ considerably in size and appearance. The males vary from five-eighths 

 to three-fourths of an inch in length and from one inch to one and one-eighth 

 inches in expanse. The females are larger, measuring about seven-eighths 

 of an inch in length by one and one-half inches in expanse. The general 

 color of both sexes is dark, lustrous brown. There are bands of orange and 

 lemon-yellow scales encircling the abdomen and spots of similar colored 

 scales at the base of the wings. As the moths grow old and worn with flight 

 these bright colors fade or disappear. 



During the investigation of this species moths were first seen on the 

 wing on July 24th and for about fifteen days thereafter they were abundant. 

 The males appeared a few days in advance of the females and during the 

 period of their flight were more abundant than those of the other sex. 



The moth in its color, structure and flight resembles very closely the 

 common stinging wasps of the genus Polistes. Both sexes have a habit of 

 alighting on some object and fluttering their wings with an angry, buzzing 

 sound which adds very greatly to their formidable appearance. They are 

 active by day and oviposition takes place only during the brighter part of the 

 day. usually from 9 a. m. to 4 p. m. 



Natural Enemies. 



The larva of one of our common firefly insects, Photuris pennsylvanica, 

 was found devouring a pupa of the grapevine root-borer. The crested fly- 

 catcher. Myiarchus crinitus, a common bird in the locality where the investi- 

 gation was made, was observed to be feeding rather extensively on the 

 moths as they flew about, the vines. 



Methods of Control. 



This borer will be found to be a difficult pest to deal with. Methods 

 which are used with success against several species of fruit tree borers are 

 not applicable to the grapevine root-borer. The digging out process, protect- 

 ing the trunks with mechanical appliances and paints and washes cannot 

 be recommended for the present species. Its habits of burrowing down 



