958. The Aravos

136:5  The arava (willow) has extended leaves, smooth edges and a red stem, though if its stem is green, the arava is still kosher because the stem turns red when it remains on the tree. Most of this species grows near rivers, which is why it's called "arvei nachal" (willows of the river), but if it grew in a different place, it is nevertheless still valid for use. However, if possible, one should be diligent to use those that grow near a river. The minimum length of the arava is the same as for the hadas.

136:6  If the arava has dried up, if most of its leaves have fallen off, or if the top of its stem is broken off, it is invalid. Some say that if (most of – OC 647:2) the leaves are withered and drooping, then the arava is invalid. One must watch the arava carefully because the leaves may sometimes fall off when inserting it into the lulav or while waving; this would render it invalid.