Here is a very interesting video made by the US Department of Agriculture instructing farmers on how to grow and harvest hemp. It was made in 1937 and says "now with Phillipine and East Indian sources of hemp in the hands of the Japanese, and shipments of jute from India curtailed, American hemp must meet the needs of our army and navy". So the USDA saw fit to ask American farmers to grow fiber for ropes and twine. It's ten and a half minutes long. Apparently the movie disappeared soon after being made, but was discovered and distributed thanks to Mia Farrow. Who knows how SHE got it. But anyway, check it out if you have ten minutes and an interest in a very useful crop.
Aside: Ron Paul says the best source of ethanol is from hemp, not corn or sugarcane. Saw that on youtube too.