Flower wind to move pollen from one flower to the next. Examples include grasses, birch trees, ragweed and maples. They have no need to attract pollinators and therefore tend not to be "showy" flowers. Male and female reproductive organs are generally found in separate flowers, the male flowers having a number of long filaments terminating in exposed stamens, and the female flowers having long, feather-like stigmas. Whereas the pollen of animal-pollinated flowers tends to be large-grained, sticky, and rich in protein (another "reward" for pollinators), anemophilous flower pollen is usually small-grained, very light, and of little nutritional value to animals. The
Fertilisation of Orchids for transferring pollen to insects. The first mechanism described is that of "Orchis mascula", which serves as an introduction to the explanation of other Orchidaceae. In the upper part of the flower a petal shelters the male organ which has two packages of pollen grains, held together by thin elastic threads. These pollen masses stand side by side and have stalks down to adhesive balls in a cup which keeps them moist and sticky. When an insect lands on the large projecting lower petal, the labellum, and pushes its head and proboscis into the centre of the flower and down