Genus of around 56 shrub and subshrubs. Some species are termed monoecious and thus produce bisexual male and female flowers on the same plant. However most species in this genus are dioecious and thus produce unisexual male or female flowers on individual plants. Both male and female flowers are arranged in clusters, coloured white to yellow-green, with overlapping petals. Female flowers tend to be in smaller clusters or produced solitarily and tend to have hairs or warts.