Hemp promoters have long lobbied for this day.

Just before Christmas, President Trump signed the bipartisan 2018 Congressional Farm Bill, which included a provision that effectively legalizes hemp in the U.S., as long as it contains no more than 0.3% of THC, the active ingredient in marijuana that gets people high, which industrial hemp does not.

The historic law, which takes effect this month, treats hemp as an agricultural commodity and removes it from the Drug Enforcement Agency's list of schedule 1 drugs.

However, the Farm Bill empowers states to regulate (or ban) the production and sale of hemp within their borders, a move that would be counterproductive to local farmers who now have the option of growing a productive crop, while corn and soybean prices are low.

Promoters have long extolled the virtue of the grassy weed as one of the cheapest and most important crops for solving the world's problems around sustainability and health—with it's alleged ability to treat numerous symptoms and diseases. (And scientific studies support some of these claims.)

The plant, cannabis sativa, is one of the fastest growing crops and was one of the first plants to be spun into usable fiber 10,000 years ago. It is so diverse, it can be made into paper, rope, clothing, biodegradable plastics, paint, insulation, biofuel, food, and animal feed.

A hemp byproduct called cannabidiol, or "CBD oil", still has some stringent rules so not just anyone can produce and sell the product. The non-intoxicating compound found in cannabis is now technically legal, if and only if the hemp is produced by a licensed grower in a manner consistent with the Farm Bill and associated federal and state regulations.

33 states have legalized cannabis for medical purposes. Over the past six years, 10 states have legalized cannabis and marijuana for adult use, however these are all technically banned under federal law—and the Farm Bill does nothing to change that.