This issue has come up many times and the newer forms are asking for dates of ANY time you have been detained or cited - a speeding ticket is both being detained and being cited - failure to mention it would be failure to declare these and they will show when a check is done by USCIS. The N-400 instructions document states:
"Note that unless a traffic incident was alcohol or drug related, you do not need to submit documentation for traffic fines and incidents that did not involve an actual arrest if the only penalty was a fine of less than $500 and/or points on your driver's license."
It does not state you may omit the incidents, it only states you do not need to submit documentation as evidence.
With that in mind it seems clear they must be declared on the form - perhaps there is some flexibility here, but I tend to go with caution and declare everything.
With that in mind - in declaring them should I be concerned that I cannot find the exact date. I can get the receipts before interview, as I already have one coming in the mail.
Thanks again for you help and if you disagree with any of the above please let me know your thoughts and experience.
Thanks.