Questions about harvesting medicinal plants?

i’ll just give you my favorite extinct plant that became that way due to the way the Romans loved its effects. Silphium, it was actually a birth control agent in ancient times and was so widely popular that its image was even printed on coins. This is actually the only reason we even know of its existence. We can never actually know for sure if this plant did what they though it would do since we can no longer test its properties or chemical make up. 

 Hemp is an fairly useful plant, shame its unlawful to develop it in maximum places. a million) No using fact its not a vine, its a thick stem with leaves coming off. it quite is going to attain a definite top then stop growing to be. 2) It does not produce fruit it produces seeds. 3) the finished plant will die using fact its an annual plant will set seed then die interior the comparable twelve months the seeds are sown. The seeds are stored to sow destiny flora. Hemp could nicely be utilized to make cellulose, organic fibres and compost, it quite is utilized to try against soil erosion and it grows like a, er, weed.