In The American Pageant by Thomas A. Bailey, the writer is using "weed" to rephrase "tobacco":
By 1612 he had perfected methods of raising and curing the pungent weed, eliminating much of the bitter tang. ... Virginia’s prosperity was finally built on tobacco smoke. This “bewitching weed” played a vital role in putting the colony on firm economic foundations.
According to Longman Dictionary of Contemporary English
informal cigarettes or tobacco
But "weed" nowadays is also closely associated with marijuana. If I am using "the weed" in my own writing, would native speakers take it to mean "tobacco"?