Nuttall's oak vs Nuttall oak

Nuttall's oak and Nuttall oak both are nouns.

Word	Noun	Adjective	Verb	Adverb
Nuttall's oak	Yes	No	No	No
Nuttall oak	Yes	No	No	No

As nouns, Nuttall's oak and Nuttall oak are synonyms defined as:

Nuttall's oak and Nuttall oak: similar to the pin oak; grows in damp sites in Mississippi River basin

Other synonyms of Nuttall's oak include Quercus nuttalli.

Nuttall's oak (noun)	Nuttall oak (noun)
similar to the pin oak; grows in damp sites in Mississippi River basin	similar to the pin oak; grows in damp sites in Mississippi River basin