Only if the entry for that profession says so. The treaty list sets a separate minimum under each profession, and the horticulturist line is satisfied by the degree it names rather than by a professional licence.
The entry sets the bar, not the industry
People assume the credential rule is uniform because the category has one name, and it is not. Each profession in Appendix 2 carries its own line, and those lines were written separately: a few name a state or provincial licence, most name a degree, and a small number allow years of experience with a post-secondary certificate. Reading the wrong line is a quiet way to arrive at a port with the wrong paper.
Hypothetical example: a berry grower's agronomy adviser near Saint-Joachim-de-Shefford is offered a U.S. crop-consulting role and assumes she must first obtain an American licence, because a friend in another listed profession had to. Her entry asks for a degree, so the licence hunt costs her three months and answers nothing.
The reverse error is more expensive. Entries that name a licence almost always name it in the alternative to a degree, so either one satisfies them; where the only alternative offered is the Mexican Licenciatura, as under Psychologist and Registered Nurse, a Canadian baccalaureate in the same subject will not substitute for the licence. Two further points sit underneath.
A licence that a state requires in order to practise is a separate matter from the treaty's qualification rule, and satisfying one does not dispose of the other. And nothing in any of this reaches permanent residence: TN is temporary work authorisation, not a step toward a green card.