Whether a particular plant is defined halachically as a tree or not influences several areas of halacha, including:

1. What bracha one recites on its fruit.

2. What bracha one recites on its fragrance.

3. Whether the prohibition of orlah applies to its fruit.

4. How severe is the prohibition to destroy it (ba’al tashchis).

5. There are several agricultural halachos concerning kilayim, shmittah, and ma’aser, all of which are relevant only in Eretz Yisroel.

What does this have anything to do with the impending beginning of Elul and the papaya tree? Stay tuned and find out.