Reeds are made from many different materials, but it really comes down to natural cane vs. synthetic.

Cane Reeds:
It has long been believed that the best reeds in the world are made from a species of cane (Arundo donax). This type of woody grass cane is used for its deep-centered sound and rich tone quality. The most popular cane for crafting natural woodwind reeds comes from the Var region of France, but cane from other world regions is quickly gaining favor (including canes from Argentina and Spain).

Synthetic Reeds:
Synthetic woodwind reeds are made from a wide variety of materials, but each does its best to emulate the response and sound quality of a natural cane reed. The advantage of synthetic reeds is their consistency. Because they are non-organic, synthetic reeds will not change with temperature and humidity. This means the reed plays the same every time you put it on your mouthpiece. Synthetic reeds are extremely popular with jazz musicians who play on wider-tipped mouthpieces, pit orchestra players who need to pick up an instrument and have it respond right away and marching band members who are often asked to play in adverse weather conditions.