Can You Build a House With Hemp? | National Geographic

Growing industrial hemp was illegal in the United States after 1970 because the industrial plant and marijuana were considered to be the same, when in fact they are different varieties of Cannabis. In recent years, some states have changed their laws, allowing farmers to start growing industrial hemp, which is used in everything from clothing to nutritional products to building materials. Oregon grower Cliff Thomason says growing and processing hemp was stymied because it was illegal, but now a knowledge ba