Tall Stems of a Sweet Plant
Puzzle 3 of Millennial Words Hard Pack
Question is: Tall Stems of a Sweet Plant
and the answer is: SUGARCANE
Word Meaning:
SUGAR CANE — A tropical grass of the genus Saccharum (especially the species Saccharum officinarum, including hybrids) having stout, fibrous, jointed stalks, the sap of which is a source of sugar.
Definitions from Wiktionary.