The Modern Reed

The following information comes from Wikipedia:

Bassoon reeds, made of Arundo donax cane, are generally made by the players themselves. Reeds begin with a piece of cane that has been left to dry. The cane is then cut and gouged into smooth strips, leaving the bark attached. After soaking, the strip of cane is cut into the desired thickness, or profiled. This can be done by hand; it is more frequently done with a machine or tool designed for the purpose. It is then cut to the correct outline, or shaped. Making sure the cane is thoroughly soaked, to avoid cracking, the profiled and shaped strip of cane is folded over in the middle. The outer edges, where the bark remains after profiling, are secured by three coils of wire at 2 mm and 8 mm from the beginning of the blade, and 6 mm from the bottom. The flat piece of cane is placed on a long, thin mandrel and pressed fimrmly around it to form into the proper shape, until the bottom of the reed is rounded enough to fit securely on the end of the bocal.

After the reed has dried, the wires are tightened around the reed, which has shrunk after drying. The lower part is sealed (generally with rubber cement or epoxy) and then wrapped with string to ensure both that no air leaks out through the bottom of the reed and that the reed maintains its shape.

To finish the reed, first, the tip (previously the center of the strip of cane) is cut, so that the blades above the bark are roughly 27 mm long. The reed is then scraped with a knife until it has the proper profile, which has a thin tip leading to a thicker back section, and the "spine" going lengthwise down the center also thick. Specific measurements differ from player to player and instrument to instrument. The very tip of a reed blade is frequently only 0.1 mm thick.

As the style of reed desired varies a great deal from player to player, most advanced players will make their own reeds in order to customize them to their own individual playing style, and almost all will be familiar with the process of making one. However, several companies offer premade reeds, and several individuals also produce reeds for sale, some specializing in this over playing.