The term "kief" has been used for the powder made from glands (sometimes termed trichomes) that have been sifted or rubbed from the buds and leaves of the plant. In North America and Europe, kief is also described as the glands of the mature female plant. Kief powder refers to this loose collection. It can pressed to make hash using presses with heated iron or plates, although this is not the only method by which hash is made. In the US kief is sometimes pressed into hash, but it is more likely to be smoked or vaporized alone or used to top some bud in a pipe.