The Evolution of Marijuana Law: Chapter Six: The Question of Marijuana: Still Unanswered: by Lawrence Miller: mid 1970's page 197: is about the lobbying for Marijuana Tax Act: assuring farmers that production of fiber, oil, seed cakes will not be damaged page 199: Has graph of hemp grown by registered growers, cannabis harvested by the acre & illegal cannabis destroyed by the acre from 1938 to 1944 page 201: In the 1960's Congress ratified the Single Convention on Narcotic Drugs: took effect in US in 1967: The treaty explicitly protects cultivation of cannabis plant exclusively for industrial purposes (fiber & seed) or horticultural purposes. When federal antimarijuana laws underwent a major revision in 1970, Congress deleted mechanisms for registering growers and processors. - When the federal government abandoned regulation of commercial hemp, regulatory authority passed to the states. Each state has authority to establish a mechanism by which producers and processors of hemp can register as legitimate business enterprises, with such state certification allowing them to operate even though marijuana remains illegal - just as was done under the federal system. page 202 Wild marijuana in the United States has descended from old industrial fiber crops. Scientists have measured the drug content of such plants. Scientists find the THC content of wild marijuana in Kansas to peak at 0.06 percent in flowers, the most potent part of the plant. That level is far below the amount that French law specifies for fiber Crops. THC content of sample Indiana leaves is 0.10 percent to 0.50 percent. applying the French formula to wild marijuana descended from hemp crops in Kansas, Iowa, Minnesota, & Illinois yields X values of less than 1.