. Circular. Insects. 6 in Maryland from 16 to 70 per cent of the eggs, and as the life cycle in June was only nine days, several generations of this parasite must suc- cessfully develop in the eggs of the plum curculio, thus increasing its efficiency. The other parasites attack the larva or grub. They are 8igalphu$ curculionis Fitch and its variety rufus Riley, and Thersilochus rono- tracheli Riley. The former is of much more importance than the latter because of its greater abundance. .It is a common parasite of several other coleopterous lame and is quite widely distributed. Limited observat
. Circular. Insects. 6 in Maryland from 16 to 70 per cent of the eggs, and as the life cycle in June was only nine days, several generations of this parasite must suc- cessfully develop in the eggs of the plum curculio, thus increasing its efficiency. The other parasites attack the larva or grub. They are 8igalphu$ curculionis Fitch and its variety rufus Riley, and Thersilochus rono- tracheli Riley. The former is of much more importance than the latter because of its greater abundance. .It is a common parasite of several other coleopterous lame and is quite widely distributed. Limited observations indicate that this parasite destroys about 20 per cent of the larva? of the plum curculio. Thersilochus conotracheli has not been. ¥ia. 4.—Jarring for the plum curculio in a Georgia peach orchard (original). met with outside of New York State, and the influence it exerts in keep- ing down the curculio is perhaps very small. Besides the true parasites several predaceous beetles and ants attack and destroy the curculio larva1 as they leave the fruit to enter the soil for pupation. Their value in most cases does not equal that of the parasites. Chickens arc said to help greatty in destroying the beetles, especially in small orchards planted near the home. PREVENTIVE MEASURES. Although many methods have been proposed for lessening the injury of this pernicious pest, only a few have proven of real value. Jarring.—Among these, jarring is the method which is perhaps in. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original United States. Bureau of Entomology. Washington, Govt. print. off.
Size: 1863px × 1340px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, bookpublishe, booksubjectinsects
