Some interesting further reading:
http://www.druglibrary.org/schaffer/hem ... 2000/5.htm
According to this author, Shellie is probably right, and I have to eat my crow a bit - hemp was probably cultivated in the overwhelming majority of cases in the Western world for fiber, rope, and cloth, and it appears that as a medicinal or drug-like agent, tinctures were really the only thing used. It does make sense - the modern, ridiculously intoxicant varieties of cannabis are the result of about a hundred years of selective breeding or so, and it's quite likely the stuff back then would have just hurt one's throat if smoked. Also, what was called "hemp" wasn't necessarily cannabis, as there were several other plants that looked and grew similarly but weren't actually the same species. Finally, considering how often tobacco was mentioned for smoking purposes in the colonies, Seek's probably right too. If they'd been smoking it, they would have talked and written about it.
Fitz Ludlow Hugh's book "The Hasheesh Eater" was published around the mid-19th-century (I've known about this for a good bit), and apparently according to this author not only was it a record of strong cannabis intoxication but also something that sparked interest in the plant as a recreatonal drug, which led to hashish dens in 19th-century America that competed with opium dens - THAT I didn't actually know about.
I still find Washington's diary entry odd, though. I do wonder what the use of separating out the males and females is if you're growing on an industrial basis.