How are you doing your data entry? Do you use Data Entry – Enter a species record...? There are count boxes on that for entering measurement data. Use the plus to add the second, third, etc. measurements. If the Count Of doesn’t list what you want, you add it to the Measurement Type term list via Tools – Term Lists. Select Measurement Type where you would add, for example, DBH to the Measurement Qualifiers for Length. Note that Abundance and Length are available on Taxon occurrences.

The other ways to enter observations are via recording cards for entering multiple observations for a site visit, via the import wizard and directly into the observation hierarchy. Recording cards can be tailored to meet your needs so you could have a list of species with a column for entering DBH. The import wizard allows users to import observations from Excel files (.xls but not .xlsx) etc. Entering observations directly into the observation hierarchy is very cumbersome but is useful if, for example, you miss an observation when entering data via a recording card.