Resin
The resin content is one essential point of distinction between hemp-derived CBD and marijuana-derived CBD. Cannabis resin is present in the trichomes (part of plant that contains the THC that gets you high) of buds and, to some degree, on the leaves.
Marijuana plants typically contain substantial amounts of resin, while hemp plants have much less. Marijuana provides much more CBD than hemp so larger amounts of hemp are needed to retrieve the chemical.
The exception to this is the development of some new craft hemp strains that contain high concentrations of CBD of 12 and 20 percent.
Contamination
A major risk exists when it comes to possible contamination levels of CBD due to how and where it is sourced. Because of the absence of strict regulations around the production and refinement of hemp, highly contaminated CBD products could be produced. An example of this is in China where there are few regulations in agriculture. This lack of laws governing production has led to hemp-derived CBD from China being high in contaminants.
HEMP
Between hemp and marijuana, hemp is the most utilitarian of the two plants. The difference in hemp versus marijuana is that hemp has had a wide array of uses for more than 10,000 years: fiber (from the stems), protein (from the seeds), oils and smokable parts (from leaves and flowers). Hemp has been used to produce items such as clothing, rope, paper, furnishing fabric, rope and building materials. The entire plant can be used to create feedstock and fuel.
Although very minimal, hemp does contain THC but not enough to get you high. If you are trying to achieve the medicinal benefits of the rich cannabinoids of hemp, you would be better served consuming hemp-derived CBD products.
The uses of hemp, CBD and marijuana are vast and varied. Before you decide to use medicinal cannabis stevia, consult your doctor for any possible interactions with other medicines you are taking.