Allium ×proliferum (Moench) Schrad. ex Willd. [cepa × fistulosum]

Allium ×proliferum (Moench) Schrad. ex Willd. [cepa × fistulosum]. The tree onion is a perennial plant similar to the common onion (A. cepa), but with a cluster of bulblets where a normal onion would have flowers. Tree onions are also known as Spring onions, Green onions, topsetting onions, walking onions, or Egyptian onions. Genomic evidence has suggested that they may be a diploid hybrid of the shallot and the Welsh onion (A. fistulosum). Other sources treat the tree onion as A. cepa var. proliferum or A. cepa Proliferum Group.