Any stats people out there?

[Griffith Gilbert]

I have 107 willow occurences (individual trees).  Let's call these the 
Sampling Units (SUs).  I have 8 quantitative environmental/physical 
variables (e.g. elevation, valley width, stream slope, etc.) measured 
around each SU.  Therefore, I have 107 rows and 8 columns in my dataset.  
How can I find out if there exist any differences between SUs based upon 
the variables measured?