The trees are difficult to cultivate and each tree can produce from of dried beans, depending on the tree's individual character and the climate that season. The most valuable part of this cash crop are the beans inside. Each berry holds two locules containing the beans. The coffee beans are actually two seeds within the fruit; sometimes, a third seed or one seed, a peaberry, grows in the fruit at tips of the branches. These seeds are covered in two membranes; the outer one is called the "parchment coat" and the inner one is called the "silver skin".