Clarify "ID" field in BIEN_traits_traits output

[hrdawson]

How narrow is the ID field in the BIEN_traits_traits output? Is this an ID number for a given plant at a given site, or is it an ID number for a given trait of a given plant at a given site? Or an ID for a given project?

I'm looking to match multiple trait measurements for a single plant (for example, specific leaf area and leaf N content) across multiple sites. It would be very helpful indeed if the ID was a unique number for each plant.

This package is amazing and impressively powerful. I wish all trait databases had such great access. Thank you for all your time and energy to put this together!

All the best,
Hilary Rose