Birch Tree Catkins & Sunrise

Catkins are an inflorescence, or cluster, of single sexed flowers on a spike. They tend to be produced on woody shrubs and trees such as oak, alder, birch, poplar, beech, hornbeam, sweet chestnut, hazel and willow. Silver birch is monoecious, meaning both male and female flowers (catkins) are found on the same tree, from April to May. Male catkins are long and yellow-brown in colour, and hang in groups of two to four at the tips of shoots, like lambs' tails. Female catkins are smaller, short, bright green and erect. After successful pollination (by wind), female catkins thicken and change colour to a dark crimson. Masses of tiny seeds are borne in autumn, which are dispersed by wind.