May 31, 1924 
The Cambium Curculio 
379 
in Louisiana. According to Mr. Jones the larvae in feeding in the bolls seem to 
prefer to work around the stem ends. He stated that the larvae were fairly 
common in the bolls but that he was unable to decide whether they cause primary 
njury or follow other injury. 
The writer has made repeated unsuccessful attempts to rear larvae of the 
cambium curculio in sound peaches and apples. In these experiments the 
beetles deposited their eggs freely in the fuzz on the surface of peaches but the 
larvae on hatching did not enter the fruit. When the skin and flesh of peaches 
and apples were cut, however, the beetles oviposited in the wounds and the larvae 
developed successfully in the fruit. 
Observations made over a period of several years in West Virginia, where this 
insect is abundant, indicate that the normal place for oviposition and larval 
development is around the borders of fresh wounds in the bark of many kinds of 
orchard and forest trees. The writer has captured beetles and found the larvae 
feeding at bark wounds in the following species of trees: Apple, Malus sylvestris; 
pear, Pyrus communis; pignut, Hicoria glabra; American hornbeam, Carpinus 
caroliniana; sweet birch, Betula lenta; American beech, Fagus grandifolia; Ameri¬ 
can chestnut, Castanea dentata; white oak, Quercus alba; chestnut oak, Q. montana; 
red oak, Q. borealis maxima; tulip tree, Liriodendron tulipifera; service berry, 
Amelanchier canadensis; red maple, Acer rubrum; tupelo, Nyssa sylvatica; flowering 
dogwood, Cornus florida; and sourwood, Oxydendrum arboreum. The bark 
of many of these trees was scarified for the purpose of attracting the insects. 
Both larvae and beetles, however, were observed and collected under other 
conditions. They were found in great numbers in stumps and ends of logs cut in 
the forest for lumbering purposes, feeding about wounds in apple bark made by 
falling hailstones, and feeding in apple bark at edge of wounds made in pruning; 
larvae were found in wounds in dogwood bark made by boring larvae of Aegeria 
sp., in ax wounds made by lumbermen in trunks of tulip and dogwood trees, and 
in the edge of wounds in sweet birch made by boys in peeling bark for camp 
shelter; beetles were found hiding in fresh perforations made in pear bark by 
the yellow-bellied sapsucker, Sphyrapicus varius varius; were jarred from trees 
of peach, plum, and black walnut, Juglans nigra, and were found hiding in curled 
leaves on a hickory tree. 
It is not unusual to find in June and July as many as a score of larvae feeding 
around a single wound in the bark of a tree trunk. In one case 24 larvae were 
taken from the edge of a wound in apple bark and in another 38 larvae were found 
under a small piece of bark at a wound in chestnut. Very little preference is 
shown for particular species of trees, although apple and pear seem to be especially 
attractive. Beetles, however, were attracted to every trapping place made in 
June, regardless of the species of tree used, and later the larvae were always 
present. 
NATURE OF INJURY 
Observations have shown that the cambium curculio is injurious in two distinct 
ways. It attacks the fruit of the peach and enlarges and prevents the healing 
of wounds in the bark of various kinds of trees (PI. 1, C). While neither 
Jenne nor the writer found cases of injury to sound peaches, Snapp discovered 
that a small proportion of wormy peaches in Georgia is apparently due to this 
insect. There is also a possibility that sound cotton bolls are attacked and 
injured by the larvae, as has been pointed out by Jones. The larvae, in feeding 
in the bark, mine inward through the cambium from the edges of fresh wounds 
(PI. 1, C). They do not mine extensively, but their feeding area, which is 
usually in the form of a band around the wound, varies from half an inch to 2 
inches in width. Throughout this band all the cambium is likely to be destroyed 
and the wound enlarged to that extent. As the wound grows old the larvae 
cease to attack. 
