Grasses are wind pollinated, as are some of our native trees and shrubs, such as beech (Nothofagus species), kawakawa (Macropiper excelsum, pepper tree) and many Coprosma species. Pollination by the wind is very hit and miss. The wind may pick up pollen from a grass flower and scatter it all over the place. Only by chance will a little pollen land on another flower of the same species. To make up for this waste, wind-pollinated flowers produce a huge amount of pollen, as hay fever sufferers will know.
Wind-pollinated flowers tend to have small dull-coloured petals or, in the case of grasses, no petals at all. They don’t need petals, colour, nectar or scent to attract animals. The pollen grains are not sticky like those of animal-pollinated flowers, which reduces the chance of them sticking to leaves and other obstacles. The stigmas of receiving flowers are sticky in order to hold on to pollen carried by passing breezes.