Forms of cannabis Marijuana is the most common and least powerful form of cannabis. It is the dried leaves and flowers of the plant. Its texture can be fine or coarse. It can contain seeds and twigs from the plant. The flowers or 'heads' are the most potent part of the plant and so the potency of marijuana will depend upon the amount of leaf and heads it contains.
Blocks range in colour from light brown to nearly black.
The concentration of THC in hashish is higher than marijuana, producing stronger effects. Hash is added to tobacco and smoked, or baked and eaten in foods such as hash cookies. Hash oil is a thick oily liquid, golden-brown to black, that can be extracted from hashish. It is usually spread on the tip or paper of cigarettes and then smoked. Hash oil is more powerful than the other forms of cannabis.