Tequila is a well-known drink loved by many around the world, but the agave plant is harvested for more purposes then this one liquor. Sweeteners, syrups and juices are made from agave nectar that is harvested from the center of the plant. Despite the popular conception, the agave is not a cactus plant; it is, rather, a relative of the lily family. The agave grows long spear-shaped leaves that spiral out from the center, and upon maturity the plant flowers once from the center. It is this same center that holds the sweet nectar for harvest.
Take a sharp knife and, starting at the bottom of one of the spear-shaped leaves, slide the knife upward, removing the spiny edge of the leaf. Repeat this process on the other side of the leaf and each leaf around the agave plant. Be sure to remove the sharp, black needle at the tip of the leaf as well. Removing the spines makes getting to the center of the plant easier, safer and far less painful than climbing though the spines.
Grasp the tall, cone-shaped center and carve around the base using a sharp knife. Peel back the green layer to expose the white core. Once exposed, cut out the white core. This part of the plant is heavy and may need to be taken out in several chunks.
Carve out the white, starchy plug in the center of the plant using a sharp spade or hand trowel. This will leave a round trough with thick liquid in the center exposed. This is the substance that liquors, drinks and syrups are made from.
Place one end of a rubber hose or siphon into the center liquid of the agave plant. Suck on the other end until you create a vacuum that will suck the liquid from the plant. Once the vacuum is established, place the end of the hose you were sucking on into a bucket. The rest of the liquid should empty into the vessel.