Despite 50 years of prohibition against marijuana in the United States, recent figures confirm that marijuana is ranked among corn, wheat, and soybeans as one of the four main cash crops grown in terms of dollar volume of sales. The active psychoactive ingredient in marijuana is delta-9 THC tetrahydrocannabinol , which creates mild hallucinogenic effects and acts as a depressant to the central nervous system. Similarities have been noted between mild doses of marijuana and alcohol. While all parts of the plant contain psychoactive substances, the highest THC concentrations are found in the flowering tops. The dried resinous extract from the flowering tops is called hashish or charas.
Bhang refers to the dried tops of uncultivated female plants.
The resinous mass from the smaller leaves is termed ganja. While there is no evidence of consistent tolerance or physical dependence on the drug, there is evidence of strong psychological dependence. The subjective effects of the drug are dependent upon various factors, including the dosage, means of administration, the personality of the user and circumstances in which it is used. The degree of harmful long-term side effects of the drug is a source of debate among the scientific community. The ease of cultivation and its relative cheap price also makes it the most available.