Is a burning tree an example of a plasma that occurs in nature?

No, a burning tree would not be an example of a plasma that occurs in nature. A burning tree would only be an ordinary neutral gas. Plasma is hot ionized gas that has the same amount of positively charged ions and negatively charged electrons.

NO, plasma is an ionized gas with positive ions and free electrons. A common example of plasma is Aurora, also known as polar lights. those green lights that we can see in the poles are made of plasma.

a burning tree is an example of the natural formation of gases such as carbon dioxide which is the product every burning process.