Question on nominal logistic regression output

[#1]

This is probably a simple question but I am new and learning so please work with me! I have run a nominal logistic regression in JMP pro. My data was binary resprout (y=1 / no=0) and 3 tree types (A, B, C). I am now looking at the output and wondering what is necessary to confirm that the relationship between tree type and resprouting is significant. Is it the "Whole model test," the "Parameter estimates," or the "Effect likelihood ratio test?" Also, why does the "Parameter estimates" only have 2 of my tree types and has added something called "Intercept?" 

Thank you in advance for any and all help!

[#2]

A great place to start to enrich your knowledge of JMP and answer all your questions is by reading thoroughly the JMP online documentation associated with nominal logistic regression. Here is a link to the title page with numerous hot links to more details. nominal logistic regression