Nine states and Washington, D.C. have measures legalizing recreational uses of marijuana. The drug is approved for medical purposes in a total of 29 states. But in Oregon, an oversupply of marijuana has driven down prices of the drug. This has led some worried growers to start moving towards to another product the hemp plant -- to keep their businesses profitable. Marijuana comes from the dried leaves and flowers of the Cannabis sativa or Cannabis indica plant. Hemp is another kind of cannabis. It does not have the same intoxicating effects as the widely known drug. Hemp contains less than 0.3 percent of THC, the substance that gives marijuana its powerful effect. Growing industrial hemp is legal under federal law, and the plant can be sold for use in things like cloth, food, seed and building materials.