INJURIOUS INSECTS OF I9Q09Q AND IQI1O. EDs 
A Cerambycid Beetle Infesting Black and Bur-Oaks. 
On July 3d Dr. Franklin examined some bur-oak trees in Har- 
riet Park, Minneapolis. Two large trees were in a dying condi- 
tion, and two other very good specimens were already dead. Ina 
borer-hole in the bark of one of these a beetle was found, which 
was pinned, and may be found by referring to accession reference, 
experiment 561. This was determined to be the Rustic Borer, 
Xylotrechus colonus. The presence of this beetle would seem to 
indicate that this was the species which caused the death and the 
dying condition of these trees. Several larvae were collected and 
bottled (see accession reference for experiment 561). Later, a 
large number of black oak trees in Minnehaha Park were found to 
be in a dying condition, and removal of the bark showed the work 
of a borer, which appeared exactly like that under the bark of the 
bur-oak trees in Harriet Park, above mentioned. So, while it is not 
certain, it seems probable that the Rustic Borer may have caused 
all this trouble. 
It should be noted here that in other portions of Minneapolis, 
and also in St. Paul, oaks were seen during the season to be in poor 
condition, and a large number of them to be infested with borers. 
Whether many of them were infested with this insect 1s a question. 
