Broad-Necked Root Borer lays Eggs in Captivity

Subject: large wood boring beetle?
Location: Akron, Ohio
July 2, 2015 10:10 pm
I found this 2 inch long bug yesterday crawling through the grass. We at first thought it might be Hardwood Stump Borer, but now I’m thinking it’s a Broad-Necked Root Borer. All my info coming from bug books and the internet.
Today it started laying eggs in the bottom on the jar. The kids were fascinated! I have hardwood trees as well as apple trees and grape vines. I don’t want to release it if it is going to be damaging to my trees, but I don’t want it to suffer either. If I can find what kind of beetle it is, then I can feed it or release it elsewhere. I also, could let it go once it’s done laying eggs, (unless it mates and lays eggs multiple times).
Here is a picture of the top of the beetle, the bottom, and some with the eggs (they look kind of like rice).
Signature: Sharon

Broad-Necked Root Borer
Broad-Necked Root Borer

Dear Sharon,
This is a Broad-Necked Root Borer.  According to BugGuide:  “Eggs are inserted into ground (or under litter) in groups. Larvae tunnel downward to feed on living roots of a variety of trees and shrubs. At first they may feed on bark, but then proceed to hollow out small roots. Pupation occurs in spring, about 10 cm under the ground. Life cycle probably three years.”
  There is no indication that the feeding habits of the larvae compromise the life of a healthy tree as they feed on the small roots only.  Many gardeners feel that trimming roots helps to stimulate new growth.  We would advise you to release this magnificent beetle.  Thank you for supplying an image with the eggs.  Some female insects emerge from pupation so filled with eggs that they release some unfertilized eggs to enable them to fly better.

Broad-Necked Root Borer lays Eggs
Broad-Necked Root Borer lays Eggs

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