What does the cryptic crossword clue "American university's short tree or shrub (6)" mean?

The definition is "tree or shrub". The wordplay uses a deletion. CORNEL (deletion) = CORNEL; definition: "tree or shrub" The answer is CORNEL.

American university's short tree or shrub (6)

Guardian Cryptic #29325 | 25 Across | 2024-03-08 flower