Right behind caffeine, alcohol, and tobacco, marijuana is the most commonly used psychoactive (mood-altering) drug in the United States. It is estimated that 70 million Americans have tried marijuana at least once and 11.1 million Americans are current users. The average age people start smoking marijuana is under 14 years. Marijuana’s scientific name is Cannabis Sativa (the hemp plant), and it grows wild in temperate and tropical climates. Most wild marijuana is considered inferior to cultivated marijuana because it contains a low concentration of Delta -9-tetrahydrocannabinol (THC).