Short date is only the presentation of the data. Not how it is stored.
If you want to store only the date portion of your datetime in VB use DateTime.Date (instead of DateTime.Now or the default value).
For example:
Dim dt As Date = DateTime.Now
dt = dt.Date
In Access it seems you have to use the DateValue Function.
See
here[
^] for more details.
Hope that helps :)