74 DEPARTMENT OF AGRICULTURE. [Pub. Doc. 



Strawberry Crown Girdler (Otiorhynchus ovatus Linn.). 



The strawberry crown girdler is injurious to arbor vitse. 



The latter part of May our attention was called to the girdling 

 of twigs of arbor vitse in one of the larger nurseries. An ex- 

 amination of the plants showed that many of the twigs of the 

 season's growth had dried up and turned brown. In each case 

 of this drying up the twig was found to be nearly or entirely 

 girdled at a point 3 or 4 inches from the tip. At the time it 

 was impossible to discover the cause of the injury, though it 

 was evidently an insect. However, several small beetles were 

 collected on the plants. By the middle of August the amount 

 of girdling had increased so that in one variety of arbor vitse 

 nearly every plant showed signs of injury. Numbers of the 

 small beetle previously observed were then on the plants, but 

 none were observed in the act of girdling the twigs. A num- 

 ber of beetles were collected by jarring the plants. These were 

 brought to the laboratory and confined on uninjured arbor vitse 

 plants. It was then possible to observe the beetles feeding, 

 and in a few days every twig was girdled. The beetles con- 

 tinued to be active during several weeks, all having died by 

 the end of September. 



This injury to twigs of arbor vit?e is apparently the first 

 recorded. The beetle, however, is omnivorous and has been 

 recorded a number of times as injurious to the roots of young 

 evergreens. Its injury to strawberry plants is of wide occurrence. 



L^nfortunately, the identity of the insect was not determined 

 until late in the season, and the roots of the arbor vitfe were 

 not examined for injury by the larvse, as the possibility of 

 such injury was not considered. x\t that time no eggs or larv£e 

 could be discovered on the plants under observation in the 

 laboratory. Either the egg-laying season was over by the 

 middle of August or the beetles did not find conditions favor- 

 able for oviposition. 



Further observations should be made on this pest to deter- 

 mine whether the immature insects are injurious to the roots 

 of arbor vitee or to different plants. The girdling habit is of 

 some importance in nurseries as it makes the plants unsightly. 



