According to a new paper released by researchers from Cornell University, genetics plays the most important role. This is interesting considering that based on what we know so far, we had thought all this time that it was the environment the hemp was grown in, particularly the soil, that can cause it to yield illegally high levels of THC. The Cornell study involved studying 2 hemp fields; they then compared the genetic makeup of the plants in each as well as the environmental conditions in which they were grown. They found that varying environment conditions didn’t significantly alter the THC levels of hemp. What was interesting was that they found that the hemp plants with different genes seemed to cause the difference in whether they’ll yield high amounts of cannabinoids including THC.